This patch adds a extended crashkernel syntax that makes the value of reserved
system RAM dependent on the system RAM itself:
crashkernel=<range1>:<size1>[,<range2>:<size2>,...][@offset]
range=start-[end]
For example:
crashkernel=512M-2G:64M,2G-:128M
The motivation comes from distributors that configure their crashkernel
command line automatically with some configuration tool (YaST, you know ;)).
Of course that tool knows the value of System RAM, but if the user removes
RAM, then the system becomes unbootable or at least unusable and error
handling is very difficult.
This series implements this change for i386, x86_64, ia64, ppc64 and sh. That
should be all platforms that support kdump in current mainline. I tested all
platforms except sh due to the lack of a sh processor.
This patch:
This is the generic part of the patch. It adds a parse_crashkernel() function
in kernel/kexec.c that is called by the architecture specific code that
actually reserves the memory. That function takes the whole command line and
looks itself for "crashkernel=" in it.
If there are multiple occurrences, then the last one is taken. The advantage
is that if you have a bootloader like lilo or elilo which allows you to append
a command line parameter but not to remove one (like in GRUB), then you can
add another crashkernel value for testing at the boot command line and this
one overwrites the command line in the configuration then.
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cpu-hot-add should be fail if cpu is not set in cpu_possible_map. If go
ahead, the system will panic soon.
Especially, arch which requires additional_cpus= parameter should handle
this. Tested on ia64.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a cpu is disabled, move_task_off_dead_cpu() is called for tasks that have
been running on that cpu.
Currently, such a task is migrated:
1) to any cpu on the same node as the disabled cpu, which is both online
and among that task's cpus_allowed
2) to any cpu which is both online and among that task's cpus_allowed
It is typical of a multithreaded application running on a large NUMA system to
have its tasks confined to a cpuset so as to cluster them near the memory that
they share. Furthermore, it is typical to explicitly place such a task on a
specific cpu in that cpuset. And in that case the task's cpus_allowed
includes only a single cpu.
This patch would insert a preference to migrate such a task to some cpu within
its cpuset (and set its cpus_allowed to its entire cpuset).
With this patch, migrate the task to:
1) to any cpu on the same node as the disabled cpu, which is both online
and among that task's cpus_allowed
2) to any online cpu within the task's cpuset
3) to any cpu which is both online and among that task's cpus_allowed
In order to do this, move_task_off_dead_cpu() must make a call to
cpuset_cpus_allowed_locked(), a new subset of cpuset_cpus_allowed(), that will
not block. (name change - per Oleg's suggestion)
Calls are made to cpuset_lock() and cpuset_unlock() in migration_call() to set
the cpuset mutex during the whole migrate_live_tasks() and
migrate_dead_tasks() procedure.
[akpm@linux-foundation.org: build fix]
[pj@sgi.com: Fix indentation and spacing]
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace "cont" with "cgrp" and other misc renaming
This patch finishes some of the names that got missed in the great
"task containers" -> "control groups" rename. Primarily it renames
the local variable "cont" to "cgrp" in a number of places, and renames
the CONT_* enum members to CGRP_*.
This patch is not intended to have any effect on the generated code;
the output of "objdump -d kernel/cgroup.o" is unchanged.
Signed-off-by: Paul Menage <menage@google.com>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are two places that do so - the cgroups subsystem and the autofs
code.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Ian Kent <raven@themaw.net>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.
The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.
[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The pgrp field is not used widely around the kernel so it is now marked as
deprecated with appropriate comment.
The initialization of INIT_SIGNALS is trimmed because
a) they are set to 0 automatically;
b) gcc cannot properly initialize two anonymous (the second one
is the one with the session) unions. In this particular case
to make it compile we'd have to add some field initialized
right before the .pgrp.
This is the same patch as the 1ec320afdc one
(from Cedric), but for the pgrp field.
Some progress report:
We have to deprecate the pid, tgid, session and pgrp fields on struct
task_struct and struct signal_struct. The session and pgrp are already
deprecated. The tgid value is close to being such - the worst known usage
in in fs/locks.c and audit code. The pid field deprecation is mainly
blocked by numerous printk-s around the kernel that print the tsk->pid to
log.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tsk->exit_state can only be 0, EXIT_ZOMBIE, or EXIT_DEAD. A non-zero test
is the same as tsk->exit_state & (EXIT_ZOMBIE | EXIT_DEAD), so just testing
tsk->exit_state is sufficient.
Signed-off-by: Eugene Teo <eugeneteo@kernel.sg>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cause writes to cpuset "cpus" file to update cpus_allowed for member tasks:
- collect batches of tasks under tasklist_lock and then call
set_cpus_allowed() on them outside the lock (since this can sleep).
- add a simple generic priority heap type to allow efficient collection
of batches of tasks to be processed without duplicating or missing any
tasks in subsequent batches.
- make "cpus" file update a no-op if the mask hasn't changed
- fix race between update_cpumask() and sched_setaffinity() by making
sched_setaffinity() post-check that it's not running on any cpus outside
cpuset_cpus_allowed().
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Decrustify the kernel/cpuset.c 'cpus' and 'mems' updating code.
Other than subtle improvements in the consistency of identifying
white space at the beginning and end of passed in masks, this
doesn't make any visible difference in behaviour. But it's
one or two hundred kernel text bytes smaller, and easier to
understand.
[akpm@linux-foundation.org: coding-style fix]
Signed-off-by: Paul Jackson <pj@sgi.com>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new per-cpuset flag called 'sched_load_balance'.
When enabled in a cpuset (the default value) it tells the kernel scheduler
that the scheduler should provide the normal load balancing on the CPUs in
that cpuset, sometimes moving tasks from one CPU to a second CPU if the
second CPU is less loaded and if that task is allowed to run there.
When disabled (write "0" to the file) then it tells the kernel scheduler
that load balancing is not required for the CPUs in that cpuset.
Now even if this flag is disabled for some cpuset, the kernel may still
have to load balance some or all the CPUs in that cpuset, if some
overlapping cpuset has its sched_load_balance flag enabled.
If there are some CPUs that are not in any cpuset whose sched_load_balance
flag is enabled, the kernel scheduler will not load balance tasks to those
CPUs.
Moreover the kernel will partition the 'sched domains' (non-overlapping
sets of CPUs over which load balancing is attempted) into the finest
granularity partition that it can find, while still keeping any two CPUs
that are in the same shed_load_balance enabled cpuset in the same element
of the partition.
This serves two purposes:
1) It provides a mechanism for real time isolation of some CPUs, and
2) it can be used to improve performance on systems with many CPUs
by supporting configurations in which load balancing is not done
across all CPUs at once, but rather only done in several smaller
disjoint sets of CPUs.
This mechanism replaces the earlier overloading of the per-cpuset
flag 'cpu_exclusive', which overloading was removed in an earlier
patch: cpuset-remove-sched-domain-hooks-from-cpusets
See further the Documentation and comments in the code itself.
[akpm@linux-foundation.org: don't be weird]
Signed-off-by: Paul Jackson <pj@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since these are expanded into call to pid_nr_ns() anyway, it's OK to move
the whole routine out-of-line. This is a cheap way to save ~100 bytes from
vmlinux. Together with the previous two patches, it saves half-a-kilo from
the vmlinux.
Un-inline other (currently inlined) functions must be done with additional
performance testing.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The find_pid/_vpid/_pid_ns functions are used to find the struct pid by its
id, depending on whic id - global or virtual - is used.
The find_vpid() is a macro that pushes the current->nsproxy->pid_ns on the
stack to call another function - find_pid_ns(). It turned out, that this
dereference together with the push itself cause the kernel text size to
grow too much.
Move all these out-of-line. Together with the previous patch this saves a
bit less that 400 bytes from .text section.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With pid namespaces this field is now dangerous to use explicitly, so hide
it behind the helpers.
Also the pid and pgrp fields o task_struct and signal_struct are to be
deprecated. Unfortunately this patch cannot be sent right now as this
leads to tons of warnings, so start isolating them, and deprecate later.
Actually the p->tgid == pid has to be changed to has_group_leader_pid(),
but Oleg pointed out that in case of posix cpu timers this is the same, and
thread_group_leader() is more preferable.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since we've switched from using pid->nr to pid->upids->nr some
fields on struct pid are no longer needed
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The find_task_by_something is a set of macros are used to find task by pid
depending on what kind of pid is proposed - global or virtual one. All of
them are wrappers above the most generic one - find_task_by_pid_type_ns() -
and just substitute some args for it.
It turned out, that dereferencing the current->nsproxy->pid_ns construction
and pushing one more argument on the stack inline cause kernel text size to
grow.
This patch moves all this stuff out-of-line into kernel/pid.c. Together
with the next patch it saves a bit less than 400 bytes from the .text
section.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the largest patch in the set. Make all (I hope) the places where
the pid is shown to or get from user operate on the virtual pids.
The idea is:
- all in-kernel data structures must store either struct pid itself
or the pid's global nr, obtained with pid_nr() call;
- when seeking the task from kernel code with the stored id one
should use find_task_by_pid() call that works with global pids;
- when showing pid's numerical value to the user the virtual one
should be used, but however when one shows task's pid outside this
task's namespace the global one is to be used;
- when getting the pid from userspace one need to consider this as
the virtual one and use appropriate task/pid-searching functions.
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: nuther build fix]
[akpm@linux-foundation.org: yet nuther build fix]
[akpm@linux-foundation.org: remove unneeded casts]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Terminate all processes in a namespace when the reaper of the namespace is
exiting. We do this by walking the pidmap of the namespace and sending
SIGKILL to all processes.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Only the global-init process must be special - any other cgroup-init
process must be killable to prevent run-away processes in the system.
TODO: Ideally we should allow killing the cgroup-init only from parent
cgroup and prevent it being killed from within the cgroup.
But that is a more complex change and will be addressed by a follow-on
patch. For now allow the cgroup-init to be terminated by any process
with sufficient privileges.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This will help fixing memory leaks due to bad reference counting.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The namespace's proc_mnt must be kern_mount-ed to make this pointer always
valid, independently of whether the user space mounted the proc or not. This
solves raced in proc_flush_task, etc. with the proc_mnt switching from NULL
to not-NULL.
The initialization is done after the init's pid is created and hashed to make
proc_get_sb() finr it and get for root inode.
Sice the namespace holds the vfsmnt, vfsmnt holds the superblock and the
superblock holds the namespace we must explicitly break this circle to destroy
all the stuff. This is done after the init of the namespace dies. Running a
few steps forward - when init exits it will kill all its children, so no
proc_mnt will be needed after its death.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When clone() is invoked with CLONE_NEWPID, create a new pid namespace and then
create a new struct pid for the new process. Allocate pid_t's for the new
process in the new pid namespace and all ancestor pid namespaces. Make the
newly cloned process the session and process group leader.
Since the active pid namespace is special and expected to be the first entry
in pid->upid_list, preserve the order of pid namespaces.
The size of 'struct pid' is dependent on the the number of pid namespaces the
process exists in, so we use multiple pid-caches'. Only one pid cache is
created during system startup and this used by processes that exist only in
init_pid_ns.
When a process clones its pid namespace, we create additional pid caches as
necessary and use the pid cache to allocate 'struct pids' for that depth.
Note, that with this patch the newly created namespace won't work, since the
rest of the kernel still uses global pids, but this is to be fixed soon. Init
pid namespace still works.
[oleg@tv-sign.ru: merge fix]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we create new namespace we will need to allocate the struct pid, that
will have one extra struct upid in array, comparing to the parent.
Thus we need to know the new namespace (if any) in alloc_pid() to init this
struct upid properly, so move the alloc_pid() call lower in copy_process().
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When searching the task by numerical id on may need to find it using global
pid (as it is done now in kernel) or by its virtual id, e.g. when sending a
signal to a task from one namespace the sender will specify the task's virtual
id and we should find the task by this value.
[akpm@linux-foundation.org: fix gfs2 linkage]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When showing pid to user or getting the pid numerical id for in-kernel use the
value of this id may differ depending on the namespace.
This set of helpers is used to get the global pid nr, the virtual (i.e. seen
by task in its namespace) nr and the nr as it is seen from the specified
namespace.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Each struct upid element of struct pid has to be initialized properly, i.e.
its nr mst be allocated from appropriate pidmap and ns set to appropriate
namespace.
When allocating a new pid, we need to know the namespace this pid will live
in, so the additional argument is added to alloc_pid().
On the other hand, the rest of the kernel still uses the pid->nr and
pid->pid_chain fields, so these ones are still initialized, but this will be
removed soon.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Each namespace has a parent and is characterized by its "level". Level is the
number of the namespace generation. E.g. init namespace has level 0, after
cloning new one it will have level 1, the next one - 2 and so on and so forth.
This level is not explicitly limited.
True hierarchy must have some way to find each namespace's children, but it is
not used in the patches, so this ability is not added (yet).
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The first part is trivial - we just make the proc_flush_task() to operate on
arbitrary vfsmount with arbitrary ids and pass the pid and global proc_mnt to
it.
The other change is more tricky: I moved the proc_flush_task() call in
release_task() higher to address the following problem.
When flushing task from many proc trees we need to know the set of ids (not
just one pid) to find the dentries' names to flush. Thus we need to pass the
task's pid to proc_flush_task() as struct pid is the only object that can
provide all the pid numbers. But after __exit_signal() task has detached all
his pids and this information is lost.
This creates a tiny gap for proc_pid_lookup() to bring some dentries back to
tree and keep them in hash (since pids are still alive before __exit_signal())
till the next shrink, but since proc_flush_task() does not provide a 100%
guarantee that the dentries will be flushed, this is OK to do so.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make task release its namespaces after it has reparented all his children to
child_reaper, but before it notifies its parent about its death.
The reason to release namespaces after reparenting is that when task exits it
may send a signal to its parent (SIGCHLD), but if the parent has already
exited its namespaces there will be no way to decide what pid to dever to him
- parent can be from different namespace.
The reason to release namespace before notifying the parent it that when task
sends a SIGCHLD to parent it can call wait() on this taks and release it. But
releasing the mnt namespace implies dropping of all the mounts in the mnt
namespace and NFS expects the task to have valid sighand pointer.
Thanks to Oleg for pointing out some races that can apear and helping with
patches and fixes.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A pid namespace is a "view" of a particular set of tasks on the system. They
work in a similar way to filesystem namespaces. A file (or a process) can be
accessed in multiple namespaces, but it may have a different name in each. In
a filesystem, this name might be /etc/passwd in one namespace, but
/chroot/etc/passwd in another.
For processes, a process may have pid 1234 in one namespace, but be pid 1 in
another. This allows new pid namespaces to have basically arbitrary pids, and
not have to worry about what pids exist in other namespaces. This is
essential for checkpoint/restart where a restarted process's pid might collide
with an existing process on the system's pid.
In this particular implementation, pid namespaces have a parent-child
relationship, just like processes. A process in a pid namespace may see all
of the processes in the same namespace, as well as all of the processes in all
of the namespaces which are children of its namespace. Processes may not,
however, see others which are in their parent's namespace, but not in their
own. The same goes for sibling namespaces.
The know issue to be solved in the nearest future is signal handling in the
namespace boundary. That is, currently the namespace's init is treated like
an ordinary task that can be killed from within an namespace. Ideally, the
signal handling by the namespace's init should have two sides: when signaling
the init from its namespace, the init should look like a real init task, i.e.
receive only those signals, that is explicitly wants to; when signaling the
init from one of the parent namespaces, init should look like an ordinary
task, i.e. receive any signal, only taking the general permissions into
account.
The pid namespace was developed by Pavel Emlyanov and Sukadev Bhattiprolu and
we eventually came to almost the same implementation, which differed in some
details. This set is based on Pavel's patches, but it includes comments and
patches that from Sukadev.
Many thanks to Oleg, who reviewed the patches, pointed out many BUGs and made
valuable advises on how to make this set cleaner.
This patch:
We have to call exit_task_namespaces() only after the exiting task has
reparented all his children and is sure that no other threads will reparent
theirs for it. Why this is needed is explained in appropriate patch. This
one only reworks the forget_original_parent() so that after calling this a
task cannot be/become parent of any other task.
We check PF_EXITING instead of ->exit_state while choosing the new parent.
Note that tasklits_lock acts as a barrier, everyone who takes tasklist after
us (when forget_original_parent() drops it) must see PF_EXITING.
The other changes are just cleanups. They just move some code from
exit_notify to forget_original_parent(). It is a bit silly to declare
ptrace_dead in exit_notify(), take tasklist, pass ptrace_dead to
forget_original_parent(), unlock-lock-unlock tasklist, and then use
ptrace_dead.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/time/clocksource.c: Convert list_for_each to
list_for_each_entry in clocksource_resume(),
sysfs_override_clocksource() and show_available_clocksources()
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the following scenario:
code path 1:
my_function() -> lock(L1); ...; flush_workqueue(); ...
code path 2:
run_workqueue() -> my_work() -> ...; lock(L1); ...
you can get a deadlock when my_work() is queued or running
but my_function() has acquired L1 already.
This patch adds a pseudo-lock to each workqueue to make lockdep
warn about this scenario.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When someone wants to deal with some other taks's namespaces it has to lock
the task and then to get the desired namespace if the one exists. This is
slow on read-only paths and may be impossible in some cases.
E.g. Oleg recently noticed a race between unshare() and the (sent for
review in cgroups) pid namespaces - when the task notifies the parent it
has to know the parent's namespace, but taking the task_lock() is
impossible there - the code is under write locked tasklist lock.
On the other hand switching the namespace on task (daemonize) and releasing
the namespace (after the last task exit) is rather rare operation and we
can sacrifice its speed to solve the issues above.
The access to other task namespaces is proposed to be performed
like this:
rcu_read_lock();
nsproxy = task_nsproxy(tsk);
if (nsproxy != NULL) {
/ *
* work with the namespaces here
* e.g. get the reference on one of them
* /
} / *
* NULL task_nsproxy() means that this task is
* almost dead (zombie)
* /
rcu_read_unlock();
This patch has passed the review by Eric and Oleg :) and,
of course, tested.
[clg@fr.ibm.com: fix unshare()]
[ebiederm@xmission.com: Update get_net_ns_by_pid]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move alloc_pid() into copy_process(). This will keep all pid and pid
namespace code together and simplify error handling when we support multiple
pid namespaces.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
is_init() is an ambiguous name for the pid==1 check. Split it into
is_global_init() and is_container_init().
A cgroup init has it's tsk->pid == 1.
A global init also has it's tsk->pid == 1 and it's active pid namespace
is the init_pid_ns. But rather than check the active pid namespace,
compare the task structure with 'init_pid_ns.child_reaper', which is
initialized during boot to the /sbin/init process and never changes.
Changelog:
2.6.22-rc4-mm2-pidns1:
- Use 'init_pid_ns.child_reaper' to determine if a given task is the
global init (/sbin/init) process. This would improve performance
and remove dependence on the task_pid().
2.6.21-mm2-pidns2:
- [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc,
ppc,avr32}/traps.c for the _exception() call to is_global_init().
This way, we kill only the cgroup if the cgroup's init has a
bug rather than force a kernel panic.
[akpm@linux-foundation.org: fix comment]
[sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c]
[bunk@stusta.de: kernel/pid.c: remove unused exports]
[sukadev@us.ibm.com: Fix capability.c to work with threaded init]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename the child_reaper() function to task_child_reaper() to be similar to
other task_* functions and to distinguish the function from 'struct
pid_namspace.child_reaper'.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With multiple pid namespaces, a process is known by some pid_t in every
ancestor pid namespace. Every time the process forks, the child process also
gets a pid_t in every ancestor pid namespace.
While a process is visible in >=1 pid namespaces, it can see pid_t's in only
one pid namespace. We call this pid namespace it's "active pid namespace",
and it is always the youngest pid namespace in which the process is known.
This patch defines and uses a wrapper to find the active pid namespace of a
process. The implementation of the wrapper will be changed in when support
for multiple pid namespaces are added.
Changelog:
2.6.22-rc4-mm2-pidns1:
- [Pavel Emelianov, Alexey Dobriyan] Back out the change to use
task_active_pid_ns() in child_reaper() since task->nsproxy
can be NULL during task exit (so child_reaper() continues to
use init_pid_ns).
to implement child_reaper() since init_pid_ns.child_reaper to
implement child_reaper() since tsk->nsproxy can be NULL during exit.
2.6.21-rc6-mm1:
- Rename task_pid_ns() to task_active_pid_ns() to reflect that a
process can have multiple pid namespaces.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add kmem_cache to pid_namespace to allocate pids from.
Since both implementations expand the struct pid to carry more numerical
values each namespace should have separate cache to store pids of different
sizes.
Each kmem cache is name "pid_<NR>", where <NR> is the number of numerical ids
on the pid. Different namespaces with same level of nesting will have same
caches.
This patch has two FIXMEs that are to be fixed after we reach the consensus
about the struct pid itself.
The first one is that the namespace to free the pid from in free_pid() must be
taken from pid. Now the init_pid_ns is used.
The second FIXME is about the cache allocation. When we do know how long the
object will be then we'll have to calculate this size in create_pid_cachep.
Right now the sizeof(struct pid) value is used.
[akpm@linux-foundation.org: coding-style repair]
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Cedric Le Goater <clg@fr.ibm.com>
Acked-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The set of functions process_session, task_session, process_group and
task_pgrp is confusing, as the names can be mixed with each other when looking
at the code for a long time.
The proposals are to
* equip the functions that return the integer with _nr suffix to
represent that fact,
* and to make all functions work with task (not process) by making
the common prefix of the same name.
For monotony the routines signal_session() and set_signal_session() are
replaced with task_session_nr() and set_task_session(), especially since they
are only used with the explicit task->signal dereference.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a task enters a new namespace via a clone() or unshare(), a new cgroup
is created and the task moves into it.
This version names cgroups which are automatically created using
cgroup_clone() as "node_<pid>" where pid is the pid of the unsharing or
cloned process. (Thanks Pavel for the idea) This is safe because if the
process unshares again, it will create
/cgroups/(...)/node_<pid>/node_<pid>
The only possibilities (AFAICT) for a -EEXIST on unshare are
1. pid wraparound
2. a process fails an unshare, then tries again.
Case 1 is unlikely enough that I ignore it (at least for now). In case 2, the
node_<pid> will be empty and can be rmdir'ed to make the subsequent unshare()
succeed.
Changelog:
Name cloned cgroups as "node_<pid>".
[clg@fr.ibm.com: fix order of cgroup subsystems in init/Kconfig]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch is inspired by the discussion at
http://lkml.org/lkml/2007/4/11/187 and implements per cgroup statistics
as suggested by Andrew Morton in http://lkml.org/lkml/2007/4/11/263. The
patch is on top of 2.6.21-mm1 with Paul's cgroups v9 patches (forward
ported)
This patch implements per cgroup statistics infrastructure and re-uses
code from the taskstats interface. A new set of cgroup operations are
registered with commands and attributes. It should be very easy to
*extend* per cgroup statistics, by adding members to the cgroupstats
structure.
The current model for cgroupstats is a pull, a push model (to post
statistics on interesting events), should be very easy to add. Currently
user space requests for statistics by passing the cgroup file
descriptor. Statistics about the state of all the tasks in the cgroup
is returned to user space.
TODO's/NOTE:
This patch provides an infrastructure for implementing cgroup statistics.
Based on the needs of each controller, we can incrementally add more statistics,
event based support for notification of statistics, accumulation of taskstats
into cgroup statistics in the future.
Sample output
# ./cgroupstats -C /cgroup/a
sleeping 2, blocked 0, running 1, stopped 0, uninterruptible 0
# ./cgroupstats -C /cgroup/
sleeping 154, blocked 0, running 0, stopped 0, uninterruptible 0
If the approach looks good, I'll enhance and post the user space utility for
the same
Feedback, comments, test results are always welcome!
[akpm@linux-foundation.org: build fix]
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This example subsystem exports debugging information as an aid to diagnosing
refcount leaks, etc, in the cgroup framework.
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This example demonstrates how to use the generic cgroup subsystem for a
simple resource tracker that counts, for the processes in a cgroup, the
total CPU time used and the %CPU used in the last complete 10 second interval.
Portions contributed by Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the filesystem support logic from the cpusets system and makes cpusets
a cgroup subsystem
The "cpuset" filesystem becomes a dummy filesystem; attempts to mount it get
passed through to the cgroup filesystem with the appropriate options to
emulate the old cpuset filesystem behaviour.
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the following files to the cgroup filesystem:
notify_on_release - configures/reports whether the cgroup subsystem should
attempt to run a release script when this cgroup becomes unused
release_agent - configures/reports the release agent to be used for this
hierarchy (top level in each hierarchy only)
releasable - reports whether this cgroup would have been auto-released if
notify_on_release was true and a release agent was configured (mainly useful
for debugging)
To avoid locking issues, invoking the userspace release agent is done via a
workqueue task; cgroups that need to have their release agents invoked by
the workqueue task are linked on to a list.
[pj@sgi.com: Need to include kmod.h]
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace the struct css_set embedded in task_struct with a pointer; all tasks
that have the same set of memberships across all hierarchies will share a
css_set object, and will be linked via their css_sets field to the "tasks"
list_head in the css_set.
Assuming that many tasks share the same cgroup assignments, this reduces
overall space usage and keeps the size of the task_struct down (three pointers
added to task_struct compared to a non-cgroups kernel, no matter how many
subsystems are registered).
[akpm@linux-foundation.org: fix a printk]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for cgroup_clone(), a way to create new cgroups intended to
be used for systems such as namespace unsharing. A new subsystem callback,
post_clone(), is added to allow subsystems to automatically configure cloned
cgroups.
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds the necessary hooks to the fork() and exit() paths to ensure
that new children inherit their parent's cgroup assignments, and that
exiting processes release reference counts on their cgroups.
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add write_uint() helper method for cgroup subsystems
This helper is analagous to the read_uint() helper method for
reporting u64 values to userspace. It's designed to reduce the amount
of boilerplate requierd for creating new cgroup subsystems.
Signed-off-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the per-directory "tasks" file for cgroupfs mounts; this allows the
user to determine which tasks are members of a cgroup by reading a
cgroup's "tasks", and to move a task into a cgroup by writing its pid to
its "tasks".
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Generic Process Control Groups
--------------------------
There have recently been various proposals floating around for
resource management/accounting and other task grouping subsystems in
the kernel, including ResGroups, User BeanCounters, NSProxy
cgroups, and others. These all need the basic abstraction of being
able to group together multiple processes in an aggregate, in order to
track/limit the resources permitted to those processes, or control
other behaviour of the processes, and all implement this grouping in
different ways.
This patchset provides a framework for tracking and grouping processes
into arbitrary "cgroups" and assigning arbitrary state to those
groupings, in order to control the behaviour of the cgroup as an
aggregate.
The intention is that the various resource management and
virtualization/cgroup efforts can also become task cgroup
clients, with the result that:
- the userspace APIs are (somewhat) normalised
- it's easier to test e.g. the ResGroups CPU controller in
conjunction with the BeanCounters memory controller, or use either of
them as the resource-control portion of a virtual server system.
- the additional kernel footprint of any of the competing resource
management systems is substantially reduced, since it doesn't need
to provide process grouping/containment, hence improving their
chances of getting into the kernel
This patch:
Add the main task cgroups framework - the cgroup filesystem, and the
basic structures for tracking membership and associating subsystem state
objects to tasks.
Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cpuset code to present a list of tasks using a cpuset to user space could
write to an array that it had kmalloc'd, after a kmalloc request of zero size.
The problem was that the code didn't check for writes past the allocated end
of the array until -after- the first write.
This is a race condition that is likely rare -- it would only show up if a
cpuset went from being empty to having a task in it, during the brief time
between the allocation and the first write.
Prior to roughly 2.6.22 kernels, this was also a benign problem, because a
zero kmalloc returned a few usable bytes anyway, and no harm was done with the
bogus write.
With the 2.6.22 kernel changes to make issue a warning if code tries to write
to the location returned from a zero size allocation, this problem is no
longer benign. This cpuset code would occassionally trigger that warning.
The fix is trivial -- check before storing into the array, not after, whether
the array is big enough to hold the store.
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Paul Menage <menage@google.com>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is separate notifier header, but no separate notifier .c file.
Extract notifier code out of kernel/sys.c which will remain for
misc syscalls I hope. Merge kernel/die_notifier.c into kernel/notifier.c.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ssh://master.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt:
hrtimer: hook compat_sys_nanosleep up to high res timer code
hrtimer: Rework hrtimer_nanosleep to make sys_compat_nanosleep easier
Get rid of sparse related warnings from places that use integer as NULL
pointer.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds items to the taststats struct to account for user and system
time based on scaling the CPU frequency and instruction issue rates.
Adds account_(user|system)_time_scaled callbacks which architectures
can use to account for time using this mechanism.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Just removing white space at the end of lines.
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Large chunks of 5 spaces instead of tabs.
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lots of converting spaces to tabs.
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The non-filesystem capability meaning of CAP_SETPCAP is that a process, p1,
can change the capabilities of another process, p2. This is not the
meaning that was intended for this capability at all, and this
implementation came about purely because, without filesystem capabilities,
there was no way to use capabilities without one process bestowing them on
another.
Since we now have a filesystem support for capabilities we can fix the
implementation of CAP_SETPCAP.
The most significant thing about this change is that, with it in effect, no
process can set the capabilities of another process.
The capabilities of a program are set via the capability convolution
rules:
pI(post-exec) = pI(pre-exec)
pP(post-exec) = (X(aka cap_bset) & fP) | (pI(post-exec) & fI)
pE(post-exec) = fE ? pP(post-exec) : 0
at exec() time. As such, the only influence the pre-exec() program can
have on the post-exec() program's capabilities are through the pI
capability set.
The correct implementation for CAP_SETPCAP (and that enabled by this patch)
is that it can be used to add extra pI capabilities to the current process
- to be picked up by subsequent exec()s when the above convolution rules
are applied.
Here is how it works:
Let's say we have a process, p. It has capability sets, pE, pP and pI.
Generally, p, can change the value of its own pI to pI' where
(pI' & ~pI) & ~pP = 0.
That is, the only new things in pI' that were not present in pI need to
be present in pP.
The role of CAP_SETPCAP is basically to permit changes to pI beyond
the above:
if (pE & CAP_SETPCAP) {
pI' = anything; /* ie., even (pI' & ~pI) & ~pP != 0 */
}
This capability is useful for things like login, which (say, via
pam_cap) might want to raise certain inheritable capabilities for use
by the children of the logged-in user's shell, but those capabilities
are not useful to or needed by the login program itself.
One such use might be to limit who can run ping. You set the
capabilities of the 'ping' program to be "= cap_net_raw+i", and then
only shells that have (pI & CAP_NET_RAW) will be able to run
it. Without CAP_SETPCAP implemented as described above, login(pam_cap)
would have to also have (pP & CAP_NET_RAW) in order to raise this
capability and pass it on through the inheritable set.
Signed-off-by: Andrew Morgan <morgan@kernel.org>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After adding checking to register_sysctl_table and finding a whole new set
of bugs. Missed by countless code reviews and testers I have finally lost
patience with the binary sysctl interface.
The binary sysctl interface has been sort of deprecated for years and
finding a user space program that uses the syscall is more difficult then
finding a needle in a haystack. Problems continue to crop up, with the in
kernel implementation. So since supporting something that no one uses is
silly, deprecate sys_sysctl with a sufficient grace period and notice that
the handful of user space applications that care can be fixed or replaced.
The /proc/sys sysctl interface that people use will continue to be
supported indefinitely.
This patch moves the tested warning about sysctls from the path where
sys_sysctl to a separate path called from both implementations of
sys_sysctl, and it adds a proper entry into
Documentation/feature-removal-schedule.
Allowing us to revisit this in a couple years time and actually kill
sys_sysctl.
[lethal@linux-sh.org: sysctl: Fix syscall disabled build]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turns out that the net/irda code didn't register any of it's binary paths
in the global sysctl.h header file so I missed them completely when making an
authoritative list of binary sysctl paths in the kernel. So add them to the
list of valid binary sysctl paths.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Well it turns out after I dug into the problems a little more I was returning
a few false positives so this patch updates my logic to remove them.
- Don't complain about 0 ctl_names in sysctl_check_binary_path
It is valid for someone to remove the sysctl binary interface
and still keep the same sysctl proc interface.
- Count ctl_names and procnames as matching if they both don't
exist.
- Only warn about missing min&max when the generic functions care.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After going through the kernels sysctl tables several times it has become
clear that code review and testing is just not effective in prevent
problematic sysctl tables from being used in the stable kernel. I certainly
can't seem to fix the problems as fast as they are introduced.
Therefore this patch adds sysctl_check_table which is called when a sysctl
table is registered and checks to see if we have a problematic sysctl table.
The biggest part of the code is the table of valid binary sysctl entries, but
since we have frozen our set of binary sysctls this table should not need to
change, and it makes it much easier to detect when someone unintentionally
adds a new binary sysctl value.
As best as I can determine all of the several hundred errors spewed on boot up
now are legitimate.
[bunk@kernel.org: kernel/sysctl_check.c must #include <linux/string.h>]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It looks like we inadvertently killed the cad_pid binary sysctl support when
cap_pid was changed to be a struct pid. Since no one has complained just
remove the binary path.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of having a bunch of ifdefs in sysctl.c move all of the pty sysctl
logic into drivers/char/pty.c
As well as cleaning up the logic this prevents sysctl_check_table from
complaining that the root table has a NULL data pointer on something with
generic methods.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
aio-nr, aio-max-nr, acpi_video_flags are unsigned long values which sysctl
does not handle properly with a 64bit kernel and a 32bit user space.
Since no one is likely to be using the binary sysctl values and the ascii
interface still works, this patch just removes support for the binary sysctl
interface from the kernel.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These functions are all wrapper functions for the proc interface that are
needed for them to work correctly.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Acked-by: Andrew Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There as been no easy way to wrap the default sysctl strategy routine except
for returning 0. Which is not always what we want. The few instances I have
seen that want different behaviour have written their own version of
sysctl_data. While not too hard it is unnecessary code and has the potential
for extra bugs.
So to make these situations easier and make that part of sysctl more symetric
I have factord sysctl_data out of do_sysctl_strategy and exported as a
function everyone can use.
Further having sysctl_data be an explicit function makes checking for badly
formed sysctl tables much easier.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In sysctl.h the typedef struct ctl_table ctl_table violates coding style isn't
needed and is a bit of a nuisance because it makes it harder to recognize
ctl_table is a type name.
So this patch removes it from the generic sysctl code. Hopefully I will have
enough energy to send the rest of my patches will follow and to remove it from
the rest of the kernel.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The functions in a CPU notifier chain is called with CPU_UP_PREPARE event
before making the CPU online. If one of the callback returns NOTIFY_BAD, it
stops to deliver CPU_UP_PREPARE event, and CPU online operation is canceled.
Then CPU_UP_CANCELED event is delivered to the functions in a CPU notifier
chain again.
This CPU_UP_CANCELED event is delivered to the functions which have been
called with CPU_UP_PREPARE, not delivered to the functions which haven't been
called with CPU_UP_PREPARE.
The problem that makes existing cpu hotplug error handlings complex is that
the CPU_UP_CANCELED event is delivered to the function that has returned
NOTIFY_BAD, too.
Usually we don't expect to call destructor function against the object that
has failed to initialize. It is like:
err = register_something();
if (err) {
unregister_something();
return err;
}
So it is natural to deliver CPU_UP_CANCELED event only to the functions that
have returned NOTIFY_OK with CPU_UP_PREPARE event and not to call the function
that have returned NOTIFY_BAD. This is what this patch is doing.
Otherwise, every cpu hotplug notifiler has to track whether notifiler event is
failed or not for each cpu. (drivers/base/topology.c is doing this with
topology_dev_map)
Similary this patch makes same thing with CPU_DOWN_PREPARE and CPU_DOWN_FAILED
evnets.
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If memchr argument is longer than strlen(kp->name), there will be some
weird result.
It will casuse duplicate filenames in sysfs for the "nousb". kernel
warning messages are as bellow:
sysfs: duplicate filename 'usbcore' can not be created
WARNING: at fs/sysfs/dir.c:416 sysfs_add_one()
[<c01c4750>] sysfs_add_one+0xa0/0xe0
[<c01c4ab8>] create_dir+0x48/0xb0
[<c01c4b69>] sysfs_create_dir+0x29/0x50
[<c024e0fb>] create_dir+0x1b/0x50
[<c024e3b6>] kobject_add+0x46/0x150
[<c024e2da>] kobject_init+0x3a/0x80
[<c053b880>] kernel_param_sysfs_setup+0x50/0xb0
[<c053b9ce>] param_sysfs_builtin+0xee/0x130
[<c053ba33>] param_sysfs_init+0x23/0x60
[<c024d062>] __next_cpu+0x12/0x20
[<c052aa30>] kernel_init+0x0/0xb0
[<c052aa30>] kernel_init+0x0/0xb0
[<c052a856>] do_initcalls+0x46/0x1e0
[<c01bdb12>] create_proc_entry+0x52/0x90
[<c0158d4c>] register_irq_proc+0x9c/0xc0
[<c01bda94>] proc_mkdir_mode+0x34/0x50
[<c052aa30>] kernel_init+0x0/0xb0
[<c052aa92>] kernel_init+0x62/0xb0
[<c0104f83>] kernel_thread_helper+0x7/0x14
=======================
kobject_add failed for usbcore with -EEXIST, don't try to register things with the same name in the same directory.
[<c024e466>] kobject_add+0xf6/0x150
[<c053b880>] kernel_param_sysfs_setup+0x50/0xb0
[<c053b9ce>] param_sysfs_builtin+0xee/0x130
[<c053ba33>] param_sysfs_init+0x23/0x60
[<c024d062>] __next_cpu+0x12/0x20
[<c052aa30>] kernel_init+0x0/0xb0
[<c052aa30>] kernel_init+0x0/0xb0
[<c052a856>] do_initcalls+0x46/0x1e0
[<c01bdb12>] create_proc_entry+0x52/0x90
[<c0158d4c>] register_irq_proc+0x9c/0xc0
[<c01bda94>] proc_mkdir_mode+0x34/0x50
[<c052aa30>] kernel_init+0x0/0xb0
[<c052aa92>] kernel_init+0x62/0xb0
[<c0104f83>] kernel_thread_helper+0x7/0x14
=======================
Module 'usbcore' failed to be added to sysfs, error number -17
The system will be unstable now.
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On platforms that copy sys_tz into the vdso (currently only x86_64, soon to
include powerpc), it is possible for the vdso to get out of sync if a user
calls (admittedly unusual) settimeofday(NULL, ptr).
This patch adds a hook for architectures that set
CONFIG_GENERIC_TIME_VSYSCALL to ensure when sys_tz is updated they can also
updatee their copy in the vdso.
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hell knows what happened in commit 63b05203af57e7de4f3bb63b8b81d43bc196d32b
during 2.6.9 development. Commit introduced io_wait field which remained
write-only than and still remains write-only.
Also garbage collect macros which "use" io_wait.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make hibernation_platform_enter() execute the enter-a-sleep-state sequence
instead of the mixed shutdown-with-entering-S4 thing.
Replace the shutting down of devices done by kernel_shutdown_prepare(), before
entering the ACPI S4 sleep state, with suspending them and the shutting down
of sysdevs with calling device_power_down(PMSG_SUSPEND) (just like before
entering S1 or S3, but the target state is now S4). Also, disable the
nonboot CPUs before entering the sleep state (S4), which generally always is a
good idea.
This is known to fix the "double disk spin down during hibernation" on some
machines, eg. HPC nx6325 (ref. http://lkml.org/lkml/2007/8/7/316 and the
following thread). Moreover, it has been reported to make
/sys/class/rtc/rtc0/wakealarm work correctly with hibernation for some users.
It also generally causes the hibernation state (ACPI S4) to be entered faster.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The following scenario leads to total confusion of the platform firmware on
some boxes (eg. HPC nx6325):
* Hibernate with ACPI enabled
* Resume passing "acpi=off" to the boot kernel
To prevent this from happening it's necessary to check if ACPI is enabled (and
enable it if that's not the case) _right_ _after_ control has been transfered
from the boot kernel to the image kernel, before device_power_up() is called
(ie. with interrupts disabled). Enabling ACPI after calling
device_power_up() turns out to be insufficient.
For this reason, introduce new hibernation callback ->leave() that will be
executed before device_power_up() by the restored image kernel. To make it
work, it also is necessary to move swsusp_suspend() from swsusp.c to disk.c
(it's name is changed to "create_image", which is more up to the point).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the bits needed for supporting arbitrary boot kernels to the common
hibernation code.
To support arbitrary boot kernels, make it possible to replace the 'struct
new_utsname' and the kernel version in the hibernation image header by some
architecture specific data that will be used to verify if the image is valid
and to restore the image.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, there's a CONFIG_DISABLE_CONSOLE_SUSPEND that allows one to stop
the serial console from being suspended when the rest of the machine goes
to sleep. This is incredibly useful for debugging power management-related
things; however, having it as a compile-time option has proved to be
incredibly inconvenient for us (OLPC). There are plenty of times that we
want serial console to not suspend, but for the most part we'd like serial
console to be suspended.
This drops CONFIG_DISABLE_CONSOLE_SUSPEND, and replaces it with a kernel
boot parameter (no_console_suspend). By default, the serial console will
be suspended along with the rest of the system; by passing
'no_console_suspend' to the kernel during boot, serial console will remain
alive during suspend.
For now, this is pretty serial console specific; further fixes could be
applied to make this work for things like netconsole.
Signed-off-by: Andres Salomon <dilinger@debian.org>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@suspend2.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Measure the time of the freezing of tasks, even if it doesn't fail.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Increase the freezer's verbosity a bit, so that it's easier to read problem
reports related to it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes the unused EXPORT_SYMBOL(pm_power_off_prepare).
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The freezer should not send signals to kernel threads, since that may lead to
subtle problems. In particular, commit
b74d0deb96 has changed recalc_sigpending_tsk()
so that it doesn't clear TIF_SIGPENDING. For this reason, if the freezer
continues to send fake signals to kernel threads and the freezing of kernel
threads fails, some of them may be running with TIF_SIGPENDING set forever.
Accordingly, recalc_sigpending_tsk() shouldn't set the task's TIF_SIGPENDING
flag if TIF_FREEZE is set.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tasks should go to the refrigerator only if explicitly requested to do that by
the freezer and not as a result of inheriting the TIF_FREEZE flag set from the
parent. Make it happen.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The syncing of filesystems from within the freezer is generally not needed.
Also, if there's an ext3 filesystem loopback-mounted from a FUSE one, the
syncing results in writes to it and deadlocks. Similarly, it will deadlock if
FUSE implements sync.
Change freeze_processes() so that it doesn't execute sys_sync() and make the
suspend and hibernation code path sync filesystems independently of the
freezer.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename 'struct hibernation_ops' to 'struct platform_hibernation_ops' in
analogy with 'struct platform_suspend_ops'.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During hibernation we also need to tell the ACPI core that we're going to put
the system into the S4 sleep state. For this reason, an additional method in
'struct hibernation_ops' is needed, playing the role of set_target() in
'struct platform_suspend_operations'. Moreover, the role of the .prepare()
method is now different, so it's better to introduce another method, that in
general may be different from .prepare(), that will be used to prepare the
platform for creating the hibernation image (.prepare() is used anyway to
notify the platform that we're going to enter the low power state after the
image has been saved).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The variable suspend_ops representing the set of global platform-specific
suspend-related operations, used by the PM core, need not be exported outside
of kernel/power/main.c . Make it static.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is no reason why the .prepare() and .finish() methods in 'struct
platform_suspend_ops' should take any arguments, since architectures don't use
these methods' argument in any practically meaningful way (ie. either the
target system sleep state is conveyed to the platform by .set_target(), or
there is only one suspend state supported and it is indicated to the PM core
by .valid(), or .prepare() and .finish() aren't defined at all). There also
is no reason why .finish() should return any result.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The name of 'struct pm_ops' suggests that it is related to the power
management in general, but in fact it is only related to suspend. Moreover,
its name should indicate what this structure is used for, so it seems
reasonable to change it to 'struct platform_suspend_ops'. In that case, the
name of the global variable of this type used by the PM core and the names of
related functions should be changed accordingly.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
suspend_enter() can now become static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now we have high res timers on ppc64 I thought Id test them. It turns
out compat_sys_nanosleep hasnt been converted to the hrtimer code and so
is limited to HZ resolution.
The follow patch converts compat_sys_nanosleep to use high res timers.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull the copy_to_user out of hrtimer_nanosleep and into the callers
(common_nsleep, sys_nanosleep) in preparation for converting
compat_sys_nanosleep to use hrtimers.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
schedstat is useful in investigating CPU scheduler behavior. Ideally,
I think it is beneficial to have it on all the time. However, the
cost of turning it on in production system is quite high, largely due
to number of events it collects and also due to its large memory
footprint.
Most of the fields probably don't need to be full 64-bit on 64-bit
arch. Rolling over 4 billion events will most like take a long time
and user space tool can be made to accommodate that. I'm proposing
kernel to cut back most of variable width on 64-bit system. (note,
the following patch doesn't affect 32-bit system).
Signed-off-by: Ken Chen <kenchen@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
printk: add the KERN_CONT annotation (which is empty string but via
which checkpatch.pl can notice that the lacking KERN_ level is fine).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The recent wait_for_completion() cleanups:
commit 8cbbe86dfc
Author: Andi Kleen <ak@suse.de>
Date: Mon Oct 15 17:00:14 2007 +0200
sched: cleanup: refactor common code of sleep_on / wait_for_completion
Refactor common code of sleep_on / wait_for_completion
broke the return value of wait_for_completion_interruptible().
Previously it returned 0 on success, now -1. Fix that.
Problem found by Geert Uytterhoeven.
[ mingo: fixed whitespace damage ]
Reported-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Doh, I completely missed that devices marked DUMMY are not running
the set_mode function. So we force broadcasting, but we keep the
local APIC timer running.
Let the clock event layer mark the device _after_ switching it off.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch contains the following cleanups that are now possible:
- remove the unused security_operations->inode_xattr_getsuffix
- remove the no longer used security_operations->unregister_security
- remove some no longer required exit code
- remove a bunch of no longer used exports
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For those who don't care about CONFIG_SECURITY.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change migration_call(CPU_DEAD) to use direct spin_lock_irq() instead of
task_rq_lock(rq->idle), rq->idle can't change its task_rq().
This makes the code a bit more symmetrical with migrate_dead_tasks()'s path
which uses spin_lock_irq/spin_unlock_irq.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Cliff Wickman <cpw@sgi.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently move_task_off_dead_cpu() is called under
write_lock_irq(tasklist). This means it can't use task_lock() which is
needed to improve migrating to take task's ->cpuset into account.
Change the code to call move_task_off_dead_cpu() with irqs enabled, and
change migrate_live_tasks() to use read_lock(tasklist).
This all is a preparation for the futher changes proposed by Cliff Wickman, see
http://marc.info/?t=117327786100003
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Cliff Wickman <cpw@sgi.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
load_module() returns zero when mod_sysfs_init() fails, then the module
loading will succeed accidentally.
This patch makes load_module() return error correctly in that case.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compiling handle_percpu_irq only on uniprocessor generates an artificial
special case so a typical use like:
set_irq_chip_and_handler(irq, &some_irq_type, handle_percpu_irq);
needs to be conditionally compiled only on SMP systems as well and an
alternative UP construct is usually needed - for no good reason.
This fixes uniprocessor configurations for some MIPS SMP systems.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now futexfs and inotifyfs have one magic 0xBAD1DEA, that looks a
little bit confusing. Use 0xBAD1DEA as magic for futexfs and 0x2BAD1DEA as
magic for inotifyfs.
Signed-off-by: Andrey Mirkin <major@openvz.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The blessed way for standard caches is to use it. Besides, this may give
this cache a better alignment.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Cedric Le Goater <clg@fr.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For those who deselect POSIX message queues.
Reduces SLAB size of user_struct from 64 to 32 bytes here, SLUB size -- from
40 bytes to 32 bytes.
[akpm@linux-foundation.org: fix build]
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Save some space because uid_hash_find() has 3 callsites.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
.. in an effort to make read-only whatever can be made, so that
CONFIG_DEBUG_RODATA can catch as many issues as possible.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
{,un}register_timer_hook() is the API that should be used.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/sys_ni.c can't #include <linux/syscalls.h> due to cond_syscall(),
but let's tell gcc to not warn with -Wmissing-prototypes.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kconfig.preempt is not included on some archs (for example, m68k). On those
archs, the Kconfig machinery complains that KVM selects an undefined symbol
PREEMPT_NOTIFIERS (which lives in Kconfig.preempt).
So move the offending symbol into a Kconfig file which is included by
everyone.
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
robust_list, compat_robust_list, pi_state_list, pi_state_cache are
really used if futexes are on.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a prefix "VMCOREINFO_" to the vmcoreinfo macros. Old vmcoreinfo macros
were defined as generic names SYMBOL/SIZE/OFFSET /LENGTH/CONFIG, and it is
impossible to grep for them. So these names should be changed. This
discussion is the following:
http://www.ussg.iu.edu/hypermail/linux/kernel/0709.1/0415.html
Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[2/3] Add nodemask_t's size and NR_FREE_PAGES's value to vmcoreinfo_data.
The dump filetering command 'makedumpfile'(v1.1.6 or before) had assumed
the above values, and it was not good from the reliability viewpoint.
So makedumpfile v1.2.0 came to need these values and I created the patch
to let the kernel output them.
makedumpfile site:
https://sourceforge.net/projects/makedumpfile/
Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[1/3] Cleanup the coding style according to Andrew's comments:
http://lists.infradead.org/pipermail/kexec/2007-August/000522.html
- vmcoreinfo_append_str() should have suitable __attribute__s so that
the compiler can check its use.
- vmcoreinfo_max_size should have size_t.
- Use get_seconds() instead of xtime.tv_sec.
- Use init_uts_ns.name.release instead of UTS_RELEASE.
Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch set frees the restriction that makedumpfile users should install a
vmlinux file (including the debugging information) into each system.
makedumpfile command is the dump filtering feature for kdump. It creates a
small dumpfile by filtering unnecessary pages for the analysis. To
distinguish unnecessary pages, it needs a vmlinux file including the debugging
information. These days, the debugging package becomes a huge file, and it is
hard to install it into each system.
To solve the problem, kdump developers discussed it at lkml and kexec-ml. As
the result, we reached the conclusion that necessary information for dump
filtering (called "vmcoreinfo") should be embedded into the first kernel file
and it should be accessed through /proc/vmcore during the second kernel.
(http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.0/1806.html)
Dan Aloni created the patch set for the above implementation.
(http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.1/1053.html)
And I updated it for multi architectures and memory models.
(http://lists.infradead.org/pipermail/kexec/2007-August/000479.html)
Signed-off-by: Dan Aloni <da-x@monatomic.org>
Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
do_sigaction() returns -ERESTARTNOINTR if signal_pending(). The comment says:
* If there might be a fatal signal pending on multiple
* threads, make sure we take it before changing the action.
I think this is not needed. We should only worry about SIGNAL_GROUP_EXIT case,
bit it implies a pending SIGKILL which can't be cleared by do_sigaction.
Kill this special case.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
de_thread() yields waiting for ->group_leader to be a zombie. This deadlocks
if an rt-prio execer shares the same cpu with ->group_leader. Change the code
to use ->group_exit_task/notify_count mechanics.
This patch certainly uglifies the code, perhaps someone can suggest something
better.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Repost of http://lkml.org/lkml/2007/8/10/472 made available by request.
The locking used by get_random_bytes() can conflict with the
preempt_disable() and synchronize_sched() form of RCU. This patch changes
rcutorture's RNG to gather entropy from the new cpu_clock() interface
(relying on interrupts, preemption, daemons, and rcutorture's reader
thread's rock-bottom scheduling priority to provide useful entropy), and
also adds and EXPORT_SYMBOL_GPL() to make that interface available to GPLed
kernel modules such as rcutorture.
Passes several hours of rcutorture.
[ego@in.ibm.com: Use raw_smp_processor_id() in rcu_random()]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To avoid lock contention, we distribute the sched_timer calls across the
cpus so they do not trigger at the same instant. However, I used NR_CPUS,
which can cause needless grouping on small smp systems depending on your
kernel config. This patch converts to using num_possible_cpus() so we
spread it as evenly as possible on every machine.
Briefly tested w/ NR_CPUS=255 and verified reduced contention.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- remove the no longer required __attribute__((weak)) of xtime_lock
- remove the following no longer used EXPORT_SYMBOL's:
- xtime
- xtime_lock
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The child was found on ->children list under tasklist_lock, it must have a
valid ->signal. __exit_signal() both removes the task from parent->children
and clears ->signal "atomically" under write_lock(tasklist).
Remove unneeded checks.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cleanup. __group_complete_signal() wakes up ->group_exit_task twice. The
second wakeup's state includes TASK_UNINTERRUPTIBLE, which is not very
appropriate.
Change the code to pass the "correct" argument to signal_wake_up() and kill
now unneeded wake_up_process().
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The "p->exit_signal == -1 && p->ptrace == 0" check and the comment are
bogus. We already did exactly the same check in eligible_child(), we did
not drop tasklist_lock since then, and both variables need
write_lock(tasklist) to be changed.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nowadays thread_group_empty() and next_thread() are simple list operations,
this optimization doesn't make sense: we are doing exactly same check one
line below.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Two threads, T1 and T2. T2 ptraces P, and P is not a child of ptracer's
thread group. P exits and goes to TASK_ZOMBIE.
T1 does wait_task_zombie(P):
P->exit_state = TASK_DEAD;
...
read_unlock(&tasklist_lock);
T2 does exit(), takes tasklist,
forget_original_parent() does
__ptrace_unlink(P) but doesn't
call do_notify_parent(P) because
p->exit_state == EXIT_DEAD.
Now, P is not visible to our process: __ptrace_unlink() removed it from
->children. We should send notification to P->parent and release P if and
only if SIGCHLD is ignored.
And we have 3 bugs:
1. P->parent does do_wait() and gets -ECHILD (P is on ->parent->children,
but its state is TASK_DEAD).
2. // wait_task_zombie() continues
if (put_user(...)) {
// TODO: is this safe?
p->exit_state = EXIT_ZOMBIE;
return;
}
we return without notification/release, task_struct leaked.
Solution: ignore -EFAULT and proceed. It is an application's bug if
we can't fill infop/stat_addr (in case of VM_FAULT_OOM we have much
more problems).
3. // wait_task_zombie() continues
if (p->real_parent != p->parent) {
// Not taken, it was untraced'ed
...
}
release_task(p);
we released the task which we shouldn't.
Solution: check ->real_parent != ->parent before, under tasklist_lock,
but use ptrace_unlink() instead of __ptrace_unlink() to check ->ptrace.
This patch hopefully solves 2 and 3, the 1st bug will be fixed later, we need
some cleanups in forget_original_parent/reparent_thread.
However, the first race is very unlikely and not critical, so I hope it makes
sense to fix 1 and 2 for now.
4. Small cleanup: don't "restore" EXIT_ZOMBIE unless we know we are not going
to realease the child.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A zombie must have a valid ->signal, we are going to release it and
__exit_signal() starts with BUG_ON(!sig).
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With or without this patch, multi-threaded init's are not fully supported,
but do_exit() is completely wrong. This becomes a real problem when we
support pid namespaces.
1. do_exit() panics when the main thread of /sbin/init exits. It should not
until the whole thread group exits. Move the code below, under the
"if (group_dead)" check.
Note: this means that forget_original_parent() can use an already dead
child_reaper()'s task_struct. This is OK for /sbin/init because
- do_wait() from alive sub-thread still can reap a zombie, we iterate
over all sub-thread's ->children lists
- do_notify_parent() will wakeup some alive sub-thread because it sends
the group-wide signal
However, we should remove choose_new_parent()->BUG_ON(reaper->exit_state)
for this.
2. We are playing games with ->nsproxy->pid_ns. This code is bogus today, and
it has to be changed anyway when we really support pid namespaces, just
remove it.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the recent changes, do_sigaction()->recalc_sigpending_and_wake() can
never clear TIF_SIGPENDING. Instead, it can set this flag and wake up the
thread without any reason. Harmless, but unneeded and wastes CPU.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is a bit annoying that do_exit() takes ->pi_lock to set PF_EXITING. All
we need is to synchronize with lookup_pi_state() which saw this task
without PF_EXITING under ->pi_lock.
Change do_exit() to use spin_unlock_wait().
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add two new functions for reading the kernel log buffer. The intention is for
them to be used by recovery/dump/debug code so the kernel log can be easily
retrieved/parsed in a crash scenario, but they are generic enough for other
people to dream up other fun uses.
[akpm@linux-foundation.org: buncha fixes]
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Robin Getz <rgetz@blackfin.uclinux.org>
Cc: Greg Ungerer <gerg@snapgear.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch contains the following cleanups:
- make the needlessly global variable rt_trace_on static
- remove the unused global function deadlock_trace_off()
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds the /sys/module/<name>/notes/ magic directory, which has a
file for each allocated SHT_NOTE section that appears in <name>.ko. This
is the counterpart for each module of /sys/kernel/notes for vmlinux.
Reading this delivers the contents of the module's SHT_NOTE sections. This
lets userland easily glean any detailed information about that module's
build that was stored there at compile time (e.g. by ld --build-id).
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andy Gospodarek pointed out that because we return in the middle of the
free_irq() function, we never actually do call the IRQ handler that just
got deregistered. This should fix it, although I expect Andrew will want
to convert those 'return's to 'break'. That's a separate change though.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Fernando Luis Vzquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adrian Bunk points out that "unsafe" was used to mark modules touched by
the deprecated MOD_INC_USE_COUNT interface, which has long gone. It's time
to remove the member from the module structure, as well.
If you want a module which can't unload, don't register an exit function.
(Vlad Yasevich says SCTP is now safe to unload, so just remove the
__unsafe there).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Cc: Sridhar Samudrala <sri@us.ibm.com>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
smp_call_function_single() now knows how to call the function on the
current cpu.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch cleans up duplicate includes in
kernel/
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These aren't modular, so SLAB_PANIC is OK.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Control the trigger limit for softlockup warnings. This is useful for
debugging softlockups, by lowering the softlockup_thresh to identify
possible softlockups earlier.
This patch:
1. Adds a sysctl softlockup_thresh with valid values of 1-60s
(Higher value to disable false positives)
2. Changes the softlockup printk to print the cpu softlockup time
[akpm@linux-foundation.org: Fix various warnings and add definition of "two"]
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/softirq.c grew a few style uncleanlinesses in the past few
months, clean that up. No functional changes:
text data bss dec hex filename
1126 76 4 1206 4b6 softlockup.o.before
1129 76 4 1209 4b9 softlockup.o.after
( the 3 bytes .text increase is due to the "<1>" appended to one of
the printk messages. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Improve the debuggability of kernel lockups by enhancing the debug
output of the softlockup detector: print the task that causes the lockup
and try to print a more intelligent backtrace.
The old format was:
BUG: soft lockup detected on CPU#1!
[<c0105e4a>] show_trace_log_lvl+0x19/0x2e
[<c0105f43>] show_trace+0x12/0x14
[<c0105f59>] dump_stack+0x14/0x16
[<c015f6bc>] softlockup_tick+0xbe/0xd0
[<c013457d>] run_local_timers+0x12/0x14
[<c01346b8>] update_process_times+0x3e/0x63
[<c0145fb8>] tick_sched_timer+0x7c/0xc0
[<c0140a75>] hrtimer_interrupt+0x135/0x1ba
[<c011bde7>] smp_apic_timer_interrupt+0x6e/0x80
[<c0105aa3>] apic_timer_interrupt+0x33/0x38
[<c0104f8a>] syscall_call+0x7/0xb
=======================
The new format is:
BUG: soft lockup detected on CPU#1! [prctl:2363]
Pid: 2363, comm: prctl
EIP: 0060:[<c013915f>] CPU: 1
EIP is at sys_prctl+0x24/0x18c
EFLAGS: 00000213 Not tainted (2.6.22-cfs-v20 #26)
EAX: 00000001 EBX: 000003e7 ECX: 00000001 EDX: f6df0000
ESI: 000003e7 EDI: 000003e7 EBP: f6df0fb0 DS: 007b ES: 007b FS: 00d8
CR0: 8005003b CR2: 4d8c3340 CR3: 3731d000 CR4: 000006d0
[<c0105e4a>] show_trace_log_lvl+0x19/0x2e
[<c0105f43>] show_trace+0x12/0x14
[<c01040be>] show_regs+0x1ab/0x1b3
[<c015f807>] softlockup_tick+0xef/0x108
[<c013457d>] run_local_timers+0x12/0x14
[<c01346b8>] update_process_times+0x3e/0x63
[<c0145fcc>] tick_sched_timer+0x7c/0xc0
[<c0140a89>] hrtimer_interrupt+0x135/0x1ba
[<c011bde7>] smp_apic_timer_interrupt+0x6e/0x80
[<c0105aa3>] apic_timer_interrupt+0x33/0x38
[<c0104f8a>] syscall_call+0x7/0xb
=======================
Note that in the old format we only knew that some system call locked
up, we didnt know _which_. With the new format we know that it's at a
specific place in sys_prctl(). [which was where i created an artificial
kernel lockup to test the new format.]
This is also useful if the lockup happens in user-space - the user-space
EIP (and other registers) will be printed too. (such a lockup would
either suggest that the task was running at SCHED_FIFO:99 and looping
for more than 10 seconds, or that the softlockup detector has a
false-positive.)
The task name is printed too first, just in case we dont manage to print
a useful backtrace.
[satyam@infradead.org: fix warning]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
this Xen related commit:
commit 966812dc98
Author: Jeremy Fitzhardinge <jeremy@goop.org>
Date: Tue May 8 00:28:02 2007 -0700
Ignore stolen time in the softlockup watchdog
broke the softlockup watchdog to never report any lockups. (!)
print_timestamp defaults to 0, this makes the following condition
always true:
if (print_timestamp < (touch_timestamp + 1) ||
and we'll in essence never report soft lockups.
apparently the functionality of the soft lockup watchdog was never
actually tested with that patch applied ...
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sched_clock() is not a reliable time-source, use cpu_clock() instead.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of testing for overlap in the memory nodes of the the nearest
exclusive ancestor of both current and the candidate task, it is better to
simply test for intersection between the task's mems_allowed in their task
descriptors. This does not require taking callback_mutex since it is only
used as a hint in the badness scoring.
Tasks that do not have an intersection in their mems_allowed with the current
task are not explicitly restricted from being OOM killed because it is quite
possible that the candidate task has allocated memory there before and has
since changed its mems_allowed.
Cc: Andrea Arcangeli <andrea@suse.de>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adds a new sysctl, 'oom_kill_allocating_task', which will automatically kill
the OOM-triggering task instead of scanning through the tasklist to find a
memory-hogging target. This is helpful for systems with an insanely large
number of tasks where scanning the tasklist significantly degrades
performance.
Cc: Andrea Arcangeli <andrea@suse.de>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Slab constructors currently have a flags parameter that is never used. And
the order of the arguments is opposite to other slab functions. The object
pointer is placed before the kmem_cache pointer.
Convert
ctor(void *object, struct kmem_cache *s, unsigned long flags)
to
ctor(struct kmem_cache *s, void *object)
throughout the kernel
[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Based on ideas of Andrew:
http://marc.info/?l=linux-kernel&m=102912915020543&w=2
Scale the bdi dirty limit inversly with the tasks dirty rate.
This makes heavy writers have a lower dirty limit than the occasional writer.
Andrea proposed something similar:
http://lwn.net/Articles/152277/
The main disadvantage to his patch is that he uses an unrelated quantity to
measure time, which leaves him with a workload dependant tunable. Other than
that the two approaches appear quite similar.
[akpm@linux-foundation.org: fix warning]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Scale writeback cache per backing device, proportional to its writeout speed.
By decoupling the BDI dirty thresholds a number of problems we currently have
will go away, namely:
- mutual interference starvation (for any number of BDIs);
- deadlocks with stacked BDIs (loop, FUSE and local NFS mounts).
It might be that all dirty pages are for a single BDI while other BDIs are
idling. By giving each BDI a 'fair' share of the dirty limit, each one can have
dirty pages outstanding and make progress.
A global threshold also creates a deadlock for stacked BDIs; when A writes to
B, and A generates enough dirty pages to get throttled, B will never start
writeback until the dirty pages go away. Again, by giving each BDI its own
'independent' dirty limit, this problem is avoided.
So the problem is to determine how to distribute the total dirty limit across
the BDIs fairly and efficiently. A DBI that has a large dirty limit but does
not have any dirty pages outstanding is a waste.
What is done is to keep a floating proportion between the DBIs based on
writeback completions. This way faster/more active devices get a larger share
than slower/idle devices.
[akpm@linux-foundation.org: fix warnings]
[hugh@veritas.com: Fix occasional hang when a task couldn't get out of balance_dirty_pages]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Child task may be added on a different cpu that the one on which parent
is running. In which case, task_new_fair() should check whether the new
born task's parent entity should be added as well on the cfs_rq.
Patch below fixes the problem in task_new_fair.
This could fix the put_prev_task_fair() crashes reported.
Reported-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Reported-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When CONFIG_SYSFS is not set, CONFIG_FAIR_USER_SCHED fails to build
with
kernel/built-in.o: In function `uids_kobject_init':
(.init.text+0x1488): undefined reference to `kernel_subsys'
kernel/built-in.o: In function `uids_kobject_init':
(.init.text+0x1490): undefined reference to `kernel_subsys'
kernel/built-in.o: In function `uids_kobject_init':
(.init.text+0x1480): undefined reference to `kernel_subsys'
kernel/built-in.o: In function `uids_kobject_init':
(.init.text+0x1494): undefined reference to `kernel_subsys'
This patch fixes this build error.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We recently discovered a nasty performance bug in the kernel CPU load
balancer where we were hit by 50% performance regression.
When tasks are assigned to a subset of CPUs that span across
sched_domains (either ccNUMA node or the new multi-core domain) via
cpu affinity, kernel fails to perform proper load balance at
these domains, due to several logic in find_busiest_group() miss
identified busiest sched group within a given domain. This leads to
inadequate load balance and causes 50% performance hit.
To give you a concrete example, on a dual-core, 2 socket numa system,
there are 4 logical cpu, organized as:
CPU0 attaching sched-domain:
domain 0: span 0003 groups: 0001 0002
domain 1: span 000f groups: 0003 000c
CPU1 attaching sched-domain:
domain 0: span 0003 groups: 0002 0001
domain 1: span 000f groups: 0003 000c
CPU2 attaching sched-domain:
domain 0: span 000c groups: 0004 0008
domain 1: span 000f groups: 000c 0003
CPU3 attaching sched-domain:
domain 0: span 000c groups: 0008 0004
domain 1: span 000f groups: 000c 0003
If I run 2 tasks with CPU affinity set to 0x5. There are situation
where cpu0 has run queue length of 2, and cpu2 will be idle. The
kernel load balancer is unable to balance out these two tasks over
cpu0 and cpu2 due to at least three logics in find_busiest_group()
that heavily bias load balance towards power saving mode. e.g. while
determining "busiest" variable, kernel only set it when
"sum_nr_running > group_capacity". This test is flawed that
"sum_nr_running" is not necessary same as
sum-tasks-allowed-to-run-within-the sched-group. The end result is
that kernel "think" everything is balanced, but in reality we have an
imbalance and thus causing one CPU to be over-subscribed and leaving
other idle. There are two other logic in the same function will also
causing similar effect. The nastiness of this bug is that kernel not
be able to get unstuck in this unfortunate broken state. From what
we've seen in our environment, kernel will stuck in imbalanced state
for extended period of time and it is also very easy for the kernel to
stuck into that state (it's pretty much 100% reproducible for us).
So proposing the following fix: add addition logic in
find_busiest_group to detect intrinsic imbalance within the busiest
group. When such condition is detected, load balance goes into spread
mode instead of default grouping mode.
Signed-off-by: Ken Chen <kenchen@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It occurred to me this morning that the procname field was dynamically
allocated and needed to be freed. I started to put in break statements
when allocation failed but it was approaching 50% error handling code.
I came up with this alternative of looping while entry->mode is set and
checking proc_handler instead of ->table. Alternatively, the string
version of the domain name and cpu number could be stored the structs.
I verified by compiling CONFIG_DEBUG_SLAB and checking the allocation
counts after taking a cpuset exclusive and back.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
improve performance of sys_time(). sys_time() returns time in seconds,
but it does so by calling do_gettimeofday() and then returning the
tv_sec portion of the GTOD time. But the data structure "xtime", which
is updated by every timer/scheduler tick, already offers HZ granularity
time.
the patch improves the sysbench oltp macrobenchmark by 4-5% on an AMD
dual-core system:
v2.6.23:
#threads
1: transactions: 4073 (407.23 per sec.)
2: transactions: 8530 (852.81 per sec.)
3: transactions: 8321 (831.88 per sec.)
4: transactions: 8407 (840.58 per sec.)
5: transactions: 8070 (806.74 per sec.)
v2.6.23 + sys_time-speedup.patch:
1: transactions: 4281 (428.09 per sec.)
2: transactions: 8910 (890.85 per sec.)
3: transactions: 8659 (865.79 per sec.)
4: transactions: 8676 (867.34 per sec.)
5: transactions: 8532 (852.91 per sec.)
and by 4-5% on an Intel dual-core system too:
2.6.23:
1: transactions: 4560 (455.94 per sec.)
2: transactions: 10094 (1009.30 per sec.)
3: transactions: 9755 (975.36 per sec.)
4: transactions: 9859 (985.78 per sec.)
5: transactions: 9701 (969.72 per sec.)
2.6.23 + sys_time-speedup.patch:
1: transactions: 4779 (477.84 per sec.)
2: transactions: 10103 (1010.14 per sec.)
3: transactions: 10141 (1013.93 per sec.)
4: transactions: 10371 (1036.89 per sec.)
5: transactions: 10178 (1017.50 per sec.)
(the more CPUs the system has, the more speedup this patch gives for
this particular workload.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce architecture dependent kretprobe blacklists to prohibit users
from inserting return probes on the function in which kprobes can be
inserted but kretprobes can not.
This patch also removes "__kprobes" mark from "__switch_to" on x86_64 and
registers "__switch_to" to the blacklist on x86-64, because that mark is to
prohibit user from inserting only kretprobe.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the cpuset hooks that defined sched domains depending on the setting
of the 'cpu_exclusive' flag.
The cpu_exclusive flag can only be set on a child if it is set on the
parent.
This made that flag painfully unsuitable for use as a flag defining a
partitioning of a system.
It was entirely unobvious to a cpuset user what partitioning of sched
domains they would be causing when they set that one cpu_exclusive bit on
one cpuset, because it depended on what CPUs were in the remainder of that
cpusets siblings and child cpusets, after subtracting out other
cpu_exclusive cpusets.
Furthermore, there was no way on production systems to query the
result.
Using the cpu_exclusive flag for this was simply wrong from the get go.
Fortunately, it was sufficiently borked that so far as I know, almost no
successful use has been made of this. One real time group did use it to
affectively isolate CPUs from any load balancing efforts. They are willing
to adapt to alternative mechanisms for this, such as someway to manipulate
the list of isolated CPUs on a running system. They can do without this
present cpu_exclusive based mechanism while we develop an alternative.
There is a real risk, to the best of my understanding, of users
accidentally setting up a partitioned scheduler domains, inhibiting desired
load balancing across all their CPUs, due to the nonobvious (from the
cpuset perspective) side affects of the cpu_exclusive flag.
Furthermore, since there was no way on a running system to see what one was
doing with sched domains, this change will be invisible to any using code.
Unless they have real insight to the scheduler load balancing choices, they
will be unable to detect that this change has been made in the kernel's
behaviour.
Initial discussion on lkml of this patch has generated much comment. My
(probably controversial) take on that discussion is that it has reached a
rough concensus that the current cpuset cpu_exclusive mechanism for
defining sched domains is borked. There is no concensus on the
replacement. But since we can remove this mechanism, and since its
continued presence risks causing unwanted partitioning of the schedulers
load balancing, we should remove it while we can, as we proceed to work the
replacement scheduler domain mechanisms.
Signed-off-by: Paul Jackson <pj@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Dinakar Guniguntala <dino@in.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert m32r to the generic sys_ptrace. The conversion requires an
architecture hook after ptrace_attach which this patch adds. The hook
will also be needed for a conersion of ia64 to the generic ptrace code.
Thanks to Hirokazu Takata for fixing a bug in the first version of this
code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The maximum size of the huge page pool can be controlled using the overall
size of the hugetlb filesystem (via its 'size' mount option). However in the
common case the this will not be set as the pool is traditionally fixed in
size at boot time. In order to maintain the expected semantics, we need to
prevent the pool expanding by default.
This patch introduces a new sysctl controlling dynamic pool resizing. When
this is enabled the pool will expand beyond its base size up to the size of
the hugetlb filesystem. It is disabled by default.
Signed-off-by: Adam Litke <agl@us.ibm.com>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Dave McCracken <dave.mccracken@oracle.com>
Cc: William Irwin <bill.irwin@oracle.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Ken Chen <kenchen@google.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A clean up patch for "scanning memory resource [start, end)" operation.
Now, find_next_system_ram() function is used in memory hotplug, but this
interface is not easy to use and codes are complicated.
This patch adds walk_memory_resouce(start,len,arg,func) function.
The function 'func' is called per valid memory resouce range in [start,pfn).
[pbadari@us.ibm.com: Error handling in walk_memory_resource()]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch marks a number of allocations that are either short-lived such as
network buffers or are reclaimable such as inode allocations. When something
like updatedb is called, long-lived and unmovable kernel allocations tend to
be spread throughout the address space which increases fragmentation.
This patch groups these allocations together as much as possible by adding a
new MIGRATE_TYPE. The MIGRATE_RECLAIMABLE type is for allocations that can be
reclaimed on demand, but not moved. i.e. they can be migrated by deleting
them and re-reading the information from elsewhere.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cpusets try to ensure that any node added to a cpuset's mems_allowed is
on-line and contains memory. The assumption was that online nodes contained
memory. Thus, it is possible to add memoryless nodes to a cpuset and then add
tasks to this cpuset. This results in continuous series of oom-kill and
apparent system hang.
Change cpusets to use node_states[N_HIGH_MEMORY] [a.k.a. node_memory_map] in
place of node_online_map when vetting memories. Return error if admin
attempts to write a non-empty mems_allowed node mask containing only
memoryless-nodes.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@skynet.ie>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Processors on memoryless nodes must be able to fall back to remote nodes in
order to get a profiling buffer. This may lead to excessive NUMA traffic but
I think we should allow this rather than failing.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Bob Picco <bob.picco@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@skynet.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
x86(-64) are the last architectures still using the page fault notifier
cruft for the kprobes page fault hook. This patch converts them to the
proper direct calls, and removes the now unused pagefault notifier bits
aswell as the cruft in kprobes.c that was related to this mess.
I know Andi didn't really like this, but all other architecture maintainers
agreed the direct calls are much better and besides the obvious cruft
removal a common way of dealing with kprobes across architectures is
important aswell.
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix sparc64]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Andi Kleen <ak@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert cpu_sibling_map from a static array sized by NR_CPUS to a per_cpu
variable. This saves sizeof(cpumask_t) * NR unused cpus. Access is mostly
from startup and CPU HOTPLUG functions.
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Optionally add a boot delay after each kernel printk() call, crudely
measured in milliseconds, with a maximum delay of 10 seconds per printk.
Enable CONFIG_BOOT_PRINTK_DELAY=y and then add (e.g.):
"lpj=loops_per_jiffy boot_delay=100"
to the kernel command line.
It has been useful in cases like "during boot, my machine just reboots or the
screen goes black" by slowing down printk, (and adding initcall_debug), we can
usually see the last thing that happened before the lights went out which is
usually a valuable clue.
[akpm@linux-foundation.org: not all architectures implement CONFIG_HZ]
[akpm@linux-foundation.org: fix lots of stuff]
[bunk@stusta.de: kernel/printk.c: make 2 variables static]
[heiko.carstens@de.ibm.com: fix slow down printk on boot compile error]
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Identical handlers of PTRACE_DETACH go into ptrace_request().
Not touching compat code.
Not touching archs that don't call ptrace_request.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (131 commits)
NFSv4: Fix a typo in nfs_inode_reclaim_delegation
NFS: Add a boot parameter to disable 64 bit inode numbers
NFS: nfs_refresh_inode should clear cache_validity flags on success
NFS: Fix a connectathon regression in NFSv3 and NFSv4
NFS: Use nfs_refresh_inode() in ops that aren't expected to change the inode
SUNRPC: Don't call xprt_release in call refresh
SUNRPC: Don't call xprt_release() if call_allocate fails
SUNRPC: Fix buggy UDP transmission
[23/37] Clean up duplicate includes in
[2.6 patch] net/sunrpc/rpcb_clnt.c: make struct rpcb_program static
SUNRPC: Use correct type in buffer length calculations
SUNRPC: Fix default hostname created in rpc_create()
nfs: add server port to rpc_pipe info file
NFS: Get rid of some obsolete macros
NFS: Simplify filehandle revalidation
NFS: Ensure that nfs_link() returns a hashed dentry
NFS: Be strict about dentry revalidation when doing exclusive create
NFS: Don't zap the readdir caches upon error
NFS: Remove the redundant nfs_reval_fsid()
NFSv3: Always use directory post-op attributes in nfs3_proc_lookup
...
Fix up trivial conflict due to sock_owned_by_user() cleanup manually in
net/sunrpc/xprtsock.c
make sure sync wakeups preempt too - the scheduler will not
overschedule as we've got various throttles against that.
As a result, sync wakeups can be used more widely in the kernel
(to signal wakeup affinity between tasks), and no arbitrary
latencies will be introduced either.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
make sync wakeups affine for cache-cold tasks: if a cache-cold task
is woken up by a sync wakeup then use the opportunity to migrate it
straight away. (the two tasks are 'related' because they communicate)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
modify account_system_time() to add cputime to cpustat->guest if we are
running a VCPU. We add this cputime to cpustat->user instead of
cpustat->system because this part of KVM code is in fact user code
although it is executed in the kernel. We duplicate VCPU time between
guest and user to allow an unmodified "top(1)" to display correct value.
A modified "top(1)" is able to display good cpu user time and cpu guest
time by subtracting cpu guest time from cpu user time. Update "gtime" in
task_struct accordingly.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Acked-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
like for cpustat, introduce the "gtime" (guest time of the task) and
"cgtime" (guest time of the task children) fields for the
tasks. Modify signal_struct and task_struct.
Modify /proc/<pid>/stat to display these new fields.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Acked-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
we had an incorrect-terminator bug in sd_alloc_ctl_domain_table()
before, so add a comment that documents it.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now that we are calling this at runtime, a more relaxed error path is
suggested. If an allocation fails, we just register the partial table,
which will show empty directories.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Unregister and free the sysctl table before destroying domains, then
rebuild and register after creating the new domains. This prevents the
sysctl table from pointing to freed memory for root to write.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
init_sched_domain_sysctl was walking cpus 0-n and referencing per_cpu
variables. If the cpus_possible mask is not contigious this will result
in a crash referencing unallocated data. If the online mask is not
contigious then we would show offline cpus and miss online ones.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kcalloc checks for n * sizeof(element) overflows and it zeros.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In general, struct file_operations are const in the kernel, to not have
false cacheline sharing and to catch bugs at compiletime with accidental
writes to them. The new scheduler code introduces a new non-const one;
fix this up.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
activate task_hot() only for fair-scheduled tasks (i.e. disable it
for RT tasks).
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
reintroduce a simplified version of cache-hot/cold scheduling
affinity. This improves performance with certain SMP workloads,
such as sysbench.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
speed up context-switches a bit by not clearing p->exec_start.
(as a side-effect, this also makes p->exec_start a universal timestamp
available to cache-hot estimations.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Generate uevents when a user is being created/destroyed. These events
can be used to configure cpu share of a new user.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
do not normalize kernel threads via SysRq-N: the migration threads,
softlockup threads, etc. might be essential for the system to
function properly. So only zap user tasks.
pointed out by Andi Kleen.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove stale comment from sched_group_set_shares().
Function never returns -EINVAL.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Replace a particularly ugly ifdef with an inline and a new macro.
Also split up the function to be easier to read.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Refactor common code of sleep_on / wait_for_completion
These functions were largely cut'n'pasted. This moves
the common code into single helpers instead. Advantage
is about 1k less code on x86-64 and 91 lines of code removed.
It adds one function call to the non timeout version of
the functions; i don't expect this to be measurable.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Prevent wakeup over-scheduling. Once a task has been preempted by a
task of the same or lower priority, it becomes ineligible for repeated
preemption by same until it has been ticked, or slept. Instead, the
task is marked for preemption at the next tick. Tasks of higher
priority still preempt immediately.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Implement feature bit to disable forced preemption. This way
it can be checked whether a workload is overscheduling or not.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The following patch (sched: disable sleeper_fairness on SCHED_BATCH)
seems to break GROUP_SCHED. Although, it may be 'oops'-less due to the
possibility of 'p' being always a valid address.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cache_nice_tries and flags entry do not appear in proc fs sched_domain
directory, because ctl_table entry is skipped.
This patch fixes the issue.
Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
yield() in wait_task_inactive(), can cause a high priority thread to be
scheduled back in, and there by loop forever while it is waiting for some
lower priority thread which is unfortunately still on the runqueue.
Use schedule_timeout_uninterruptible(1) instead.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Credit: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add tunables in sysfs to modify a user's cpu share.
A directory is created in sysfs for each new user in the system.
/sys/kernel/uids/<uid>/cpu_share
Reading this file returns the cpu shares granted for the user.
Writing into this file modifies the cpu share for the user. Only an
administrator is allowed to modify a user's cpu share.
Ex:
# cd /sys/kernel/uids/
# cat 512/cpu_share
1024
# echo 2048 > 512/cpu_share
# cat 512/cpu_share
2048
#
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
disable sleeper fairness for batch tasks - they are about
batch processing after all.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
unit mis-match: wakeup_gran was used against a vruntime
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
export cpu_clock() - the preferred API instead of sched_clock().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
noticed by Peter Zijlstra:
fix: move the CPU check into ->task_new_fair(), this way we
can call place_entity() and get child ->vruntime right at
initial wakeup time.
(without this there can be large latencies)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
kfree(NULL) is valid.
pointed out by checkpatch.pl.
the fix shrinks the code a bit:
text data bss dec hex filename
40024 3842 100 43966 abbe sched.o.before
40002 3842 100 43944 aba8 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
run sched_domain_debug() if CONFIG_SCHED_DEBUG=y, instead
of relying on the hand-crafted SCHED_DOMAIN_DEBUG switch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
- make timeslices of SCHED_RR tasks constant and not
dependent on task's static_prio [1] ;
- remove obsolete code (timeslice related bits);
- make sched_rr_get_interval() return something more
meaningful [2] for SCHED_OTHER tasks.
[1] according to the following link, it's not compliant with SUSv3
(not sure though, what is the reference for us :-)
http://lkml.org/lkml/2007/3/7/656
[2] the interval is dynamic and can be depicted as follows "should a
task be one of the runnable tasks at this particular moment, it would
expect to run for this interval of time before being re-scheduled by the
scheduler tick".
(i.e. it's more precise if a task is runnable at the moment)
yeah, this seems to require task_rq_lock/unlock() but this is not a hot
path.
results:
(SCHED_FIFO)
dimm@earth:~/storage/prog$ sudo chrt -f 10 ./rr_interval
time_slice: 0 : 0
(SCHED_RR)
dimm@earth:~/storage/prog$ sudo chrt 10 ./rr_interval
time_slice: 0 : 99984800
(SCHED_NORMAL)
dimm@earth:~/storage/prog$ ./rr_interval
time_slice: 0 : 19996960
(SCHED_NORMAL + a cpu_hog of similar 'weight' on the same CPU --- so should be a half of the previous result)
dimm@earth:~/storage/prog$ taskset 1 ./rr_interval
time_slice: 0 : 9998480
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
optimize schedule() a bit on SMP, by moving the rq-clock update
outside the rq lock.
code size is the same:
text data bss dec hex filename
25725 2666 96 28487 6f47 sched.o.before
25725 2666 96 28487 6f47 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
The thing is that __pick_next_entity() must never be called when
first_fair(cfs_rq) == NULL. It wouldn't be a problem, should 'run_node'
be the very first field of 'struct sched_entity' (and it's the second).
The 'nr_running != 0' check is _not_ enough, due to the fact that
'current' is not within the tree. Generic paths are ok (e.g. schedule()
as put_prev_task() is called previously)... I'm more worried about e.g.
migration_call() -> CPU_DEAD_FROZEN -> migrate_dead_tasks()... if
'current' == rq->idle, no problems.. if it's one of the SCHED_NORMAL
tasks (or imagine, some other use-cases in the future -- i.e. we should
not make outer world dependent on internal details of sched_fair class)
-- it may be "Houston, we've got a problem" case.
it's +16 bytes to the ".text". Another variant is to make 'run_node' the
first data member of 'struct sched_entity' but an additional check (se !
= NULL) is still needed in pick_next_entity().
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Make vslice accurate wrt nice levels, and add some comments
while we're at it.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
mark scheduling classes as const. The speeds up the code
a bit and shrinks it:
text data bss dec hex filename
40027 4018 292 44337 ad31 sched.o.before
40190 3842 292 44324 ad24 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
There is a possibility that because of task of a group moving from one
cpu to another, it may gain more cpu time that desired. See
http://marc.info/?l=linux-kernel&m=119073197730334 for details.
This is an attempt to fix that problem. Basically it simulates dequeue
of higher level entities as if they are going to sleep. Similarly it
simulate wakeup of higher level entities as if they are waking up from
sleep.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
group scheduler SMP migration fix: use task_cfs_rq(p) to get
to the relevant fair-scheduling runqueue of a task, rq->cfs
is not the right one.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
rename all 'cnt' fields and variables to the less yucky 'count' name.
yuckage noticed by Andrew Morton.
no change in code, other than the /proc/sched_debug bkl_count string got
a bit larger:
text data bss dec hex filename
38236 3506 24 41766 a326 sched.o.before
38240 3506 24 41770 a32a sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix yield bugs due to the current-not-in-rbtree changes: the task is
not in the rbtree so rbtree-removal is a no-no.
[ From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>: build fix. ]
also, nice code size reduction:
kernel/sched.o:
text data bss dec hex filename
38323 3506 24 41853 a37d sched.o.before
38236 3506 24 41766 a326 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
group scheduler wakeup latency fix: when checking for preemption
we must check cross-group too, not just intra-group.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Lee Schermerhorn noticed that set_leftmost() contains dead code,
remove this.
Reported-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
The adjusting sched_class is a missing part of the already existing "do
not leak PI boosting priority to the child" at the sched_fork(). This
patch moves the adjusting sched_class from wake_up_new_task() to
sched_fork().
this also shrinks the code a bit:
text data bss dec hex filename
40111 4018 292 44421 ad85 sched.o.before
40102 4018 292 44412 ad7c sched.o.after
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix sched_fork(): large latencies at new task creation time because
the ->vruntime was not fixed up cross-CPU, if the parent got migrated
after the child's CPU got set up.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix sign check error in place_entity() - we'd get excessive
latencies due to negatives being converted to large u64's.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
undo some of the recent changes that are not needed after all,
such as last_min_vruntime.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
remove condition from set_task_cpu(). Now that ->vruntime
is not global anymore, it should (and does) work fine without
it too.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
entity_key() fix - we'd occasionally end up with a 0 vruntime
in the !initial case.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
debug feature: check how well we schedule within a reasonable
vruntime 'spread' range. (note that CPU overload can increase
the spread, so this is not a hard condition, but normal loads
should be within the spread.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
more width for parameter printouts in /proc/sched_debug.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
add vslice: the load-dependent "virtual slice" a task should
run ideally, so that the observed latency stays within the
sched_latency window.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
print the current value of all tunables in /proc/sched_debug output.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
add per task and per rq BKL usage statistics.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Enable user-id based fair group scheduling. This is useful for anyone
who wants to test the group scheduler w/o having to enable
CONFIG_CGROUPS.
A separate scheduling group (i.e struct task_grp) is automatically created for
every new user added to the system. Upon uid change for a task, it is made to
move to the corresponding scheduling group.
A /proc tunable (/proc/root_user_share) is also provided to tune root
user's quota of cpu bandwidth.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
With the view of supporting user-id based fair scheduling (and not just
container-based fair scheduling), this patch renames several functions
and makes them independent of whether they are being used for container
or user-id based fair scheduling.
Also fix a problem reported by KAMEZAWA Hiroyuki (wrt allocating
less-sized array for tg->cfs_rq[] and tf->se[]).
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
- Print &rq->cfs statistics as well (useful for group scheduling)
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
- print nr_running and load information for cfs_rq in /proc/sched_debug
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
- fix a minor bug in yield (seen for CONFIG_FAIR_GROUP_SCHED),
group scheduling would skew when yield was called.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
enhance debug output by changing 12345678 nsecs to 12.345678 output,
this is more human-readable.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
print the correct amount of dashes in /proc/sched_debug.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
the 'p' (task_struct) parameter in the sched_class :: yield_task() is
redundant as the caller is always the 'current'. Get rid of it.
text data bss dec hex filename
24341 2734 20 27095 69d7 sched.o.before
24330 2734 20 27084 69cc sched.o.after
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
due to the fact that we no longer keep the 'current' within the tree,
dequeue/enqueue_entity() is useless for the 'current' in
task_new_fair(). We are about to reschedule and
sched_class->put_prev_task() will put the 'current' back into the tree,
based on its new key.
text data bss dec hex filename
24388 2734 20 27142 6a06 sched.o.before
24341 2734 20 27095 69d7 sched.o.after
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix delay accounting performance regression - those sched_clock()
calls are not needed.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Get rid of 'sched_entity::fair_key'.
As a side effect, 'current' is not kept withing the tree for
SCHED_NORMAL/BATCH tasks anymore. This simplifies some parts of code
(e.g. entity_tick() and yield_task_fair()) and also somewhat optimizes
them (e.g. a single update_curr() now vs. dequeue/enqueue() before in
entity_tick()).
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
p->sched_class->set_curr_task() has to be called before
activate_task()/enqueue_task() in rt_mutex_setprio(),
sched_setschedule() and sched_move_task() in order to set up
'cfs_rq->curr'. The logic of enqueueing depends on whether a task to be
inserted is 'current' or not.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Fix a problem in the 'sched-group' patch for !CONFIG_FAIR_GROUP_SCHED.
description:
sched_setscheduler()
{
...
if (task_running()) p->sched_class->put_prev_entity();
[ this one sets up cfs_rq->curr to NULL ]
...
if (task_running) p->sched_class->set_curr_task();
[ and this one is a _NOP_ (empty) for !CONFIG_FAIR_GROUP_SCHED ]
As a result, the task continues to run with cfs_rq->curr == NULL... no
crashes (due to checks for !NULL in place) but e.g. update_curr()
effectively becomes a NOP... i.e. runtime statistics for this task is
not accounted untill it's rescheduled anew.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Add interface to control cpu bandwidth allocation to task-groups.
(not yet configurable, due to missing CONFIG_CONTAINERS)
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
fix SMP migration latencies: the vruntimes of different CPUs are
at incompatible offsets so they have to be fixed up when migrating
a task across CPUs.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Better min_vruntime tracking: update it every time 'curr' is
updated - not just when a task is enqueued into the tree.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
remove wait_runtime based fields and features, now that the CFS
math has been changed over to the vruntime metric.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
remove the wait_runtime-limit fields and the code depending on it, now
that the math has been changed over to rely on the vruntime metric.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
'struct load_stat' is redundant now so let's get rid of it.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
micro-optimization: update cfs_rq->exec_clock only if
CONFIG_SCHED_DEBUG=y.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
add more vruntime statistics.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Handle vruntime overflow by centering the key space around min_vruntime.
( otherwise we could overflow 64-bit vruntime in a few days with SCHED_IDLE
tasks - or in a few years with nice +19. )
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
add support for tree based vruntime averages.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
remove SCHED_FEAT_SKIP_INITIAL - it was off by default and even
when enabled it never made any real difference.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
clean up new task placement.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
increase wakeup granularity - we were overscheduling a bit.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
add proper new task placement for the vruntime based math too.
( note: introduces a swap() macro, but the swap token is too
widely used in the kernel namespace for a generic version
to be added without changing non-scheduler code - so this
cleanup will be done separately. )
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
optimize vruntime based scheduling.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
move sched_feat() definitions so that it can be used sooner by generic
code too.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
introduce se->vruntime as a sum of weighted delta-exec's, and use that
as the key into the tree.
the idea to use absolute virtual time as the basic metric of scheduling
has been first raised by William Lee Irwin, advanced by Tong Li and first
prototyped by Roman Zippel in the "Really Fair Scheduler" (RFS) patchset.
also see:
http://lkml.org/lkml/2007/9/2/76
for a simpler variant of this patch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
clean up calc_weighted() - we always use the normalized shift so
it's not needed to pass that in. Also, push the non-nice0 branch
into the function.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
speed up update_load_add/_sub() by not delaying the division - this
reduces CPU pipeline dependencies.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
suggested by Roman Zippel: uninline __enqueue_entity() and
__dequeue_entity().
this reduces code size:
text data bss dec hex filename
25385 2386 16 27787 6c8b sched.o.before
25257 2386 16 27659 6c0b sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Peter Zijlstra suggested to simplify SCHED_FEAT_* checks via the
sched_feat(x) macro.
No code changed:
text data bss dec hex filename
38895 3550 24 42469 a5e5 sched.o.before
38895 3550 24 42469 a5e5 sched.o.after
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
cleanup: simplify cfs_rq_curr() methods - now that the cfs_rq->curr
pointer is unconditionally present, remove the wrappers.
kernel/sched.o:
text data bss dec hex filename
11784 224 2012 14020 36c4 sched.o.before
11784 224 2012 14020 36c4 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Noticed by Roman Zippel: use cfs_rq->curr in the !group-scheduling
case too. Small micro-optimization and cleanup effect:
text data bss dec hex filename
36269 3482 24 39775 9b5f sched.o.before
36177 3486 24 39687 9b07 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
continued removal of precise CPU load calculations.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
CPU load calculations are statistical anyway, and there's little benefit
from having it calculated on every scheduling event. So remove this code,
it gets rid of a divide from the scheduler wakeup and context-switch
fastpath.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
remove the stat_gran code - it was disabled by default and it causes
unnecessary overhead.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
use constants if !CONFIG_SCHED_DEBUG.
this speeds up the code and reduces code-size:
text data bss dec hex filename
27464 3014 16 30494 771e sched.o.before
26929 3010 20 29959 7507 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
use the same defaults on both UP and SMP.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
track the maximum amount of time a task has executed while
the CPU load was at least 2x. (i.e. at least two nice-0
tasks were runnable)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
small kernel/sched_debug.c cleanup - break up
multi-variable assignment.
no code changed:
text data bss dec hex filename
38869 3550 24 42443 a5cb sched.o.before
38869 3550 24 42443 a5cb sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Use list_for_each_entry_safe() instead of list_for_each_safe() in
__wake_up_common()
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
to get full child-runs-first semantics make sure the parent is
rescheduled.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix the sched_child_runs_first flag: always call into ->task_new()
if we are on the same CPU, as SCHED_OTHER tasks depend on it for
correct initial setup.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
The 64bit SMP bootup is slightly different to the 32bit one. It enables
the boot CPU local APIC timer before all CPUs are brought up. Some AMD C1E
systems have the C1E feature flag only set in the secondary CPU. Due to
the early enable of the boot CPU local APIC timer the APIC timer is
registered as a fully functional device. When we detect the wreckage during
the bringup of the secondary CPU, we need to force the boot CPU into
broadcast mode.
Add a new notifier reason and implement the force broadcast in the clock
events layer.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
a) include/asm-um/arch can't just point to include/asm-$(SUBARCH) now
b) arch/{i386,x86_64}/crypto are merged now
c) subarch-obj needed changes
d) cpufeature_64.h should pull "cpufeature_32.h", not <asm/cpufeature_32.h>
since it can be included from asm-um/cpufeature.h
e) in case of uml-i386 we need CONFIG_X86_32 for make and gcc, but not
for Kconfig
f) sysctl.c shouldn't do vdso_enabled for uml-i386 (actually, that one
should be registered from corresponding arch/*/kernel/*, with ifdef
going away; that's a separate patch, though).
With that and with Stephen's patch ("[PATCH net-2.6] uml: hard_header fix")
we have uml allmodconfig building both on i386 and amd64.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the broadcast timer, if a timer with higher rating becomes available.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The next_event member of the clock event device is used to keep track
of the next periodic event. For one shot only devices it is wrong to
clear the variable, as the next event will be based on it.
Pointed out by Ralf Baechle
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Migration aid to allow preparatory patches which introduce not yet
used parts of clock events code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (408 commits)
[POWERPC] Add memchr() to the bootwrapper
[POWERPC] Implement logging of unhandled signals
[POWERPC] Add legacy serial support for OPB with flattened device tree
[POWERPC] Use 1TB segments
[POWERPC] XilinxFB: Allow fixed framebuffer base address
[POWERPC] XilinxFB: Add support for custom screen resolution
[POWERPC] XilinxFB: Use pdata to pass around framebuffer parameters
[POWERPC] PCI: Add 64-bit physical address support to setup_indirect_pci
[POWERPC] 4xx: Kilauea defconfig file
[POWERPC] 4xx: Kilauea DTS
[POWERPC] 4xx: Add AMCC Kilauea eval board support to platforms/40x
[POWERPC] 4xx: Add AMCC 405EX support to cputable.c
[POWERPC] Adjust TASK_SIZE on ppc32 systems to 3GB that are capable
[POWERPC] Use PAGE_OFFSET to tell if an address is user/kernel in SW TLB handlers
[POWERPC] 85xx: Enable FP emulation in MPC8560 ADS defconfig
[POWERPC] 85xx: Killed <asm/mpc85xx.h>
[POWERPC] 85xx: Add cpm nodes for 8541/8555 CDS
[POWERPC] 85xx: Convert mpc8560ads to the new CPM binding.
[POWERPC] mpc8272ads: Remove muram from the CPM reg property.
[POWERPC] Make clockevents work on PPC601 processors
...
Fixed up conflict in Documentation/powerpc/booting-without-of.txt manually.
Implement show_unhandled_signals sysctl + support to print when a process
is killed due to unhandled signals just as i386 and x86_64 does.
Default to having it off, unlike x86 that defaults on.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (867 commits)
[SKY2]: status polling loop (post merge)
[NET]: Fix NAPI completion handling in some drivers.
[TCP]: Limit processing lost_retrans loop to work-to-do cases
[TCP]: Fix lost_retrans loop vs fastpath problems
[TCP]: No need to re-count fackets_out/sacked_out at RTO
[TCP]: Extract tcp_match_queue_to_sack from sacktag code
[TCP]: Kill almost unused variable pcount from sacktag
[TCP]: Fix mark_head_lost to ignore R-bit when trying to mark L
[TCP]: Add bytes_acked (ABC) clearing to FRTO too
[IPv6]: Update setsockopt(IPV6_MULTICAST_IF) to support RFC 3493, try2
[NETFILTER]: x_tables: add missing ip6t_modulename aliases
[NETFILTER]: nf_conntrack_tcp: fix connection reopening
[QETH]: fix qeth_main.c
[NETLINK]: fib_frontend build fixes
[IPv6]: Export userland ND options through netlink (RDNSS support)
[9P]: build fix with !CONFIG_SYSCTL
[NET]: Fix dev_put() and dev_hold() comments
[NET]: make netlink user -> kernel interface synchronious
[NET]: unify netlink kernel socket recognition
[NET]: cleanup 3rd argument in netlink_sendskb
...
Fix up conflicts manually in Documentation/feature-removal-schedule.txt
and my new least favourite crap, the "mod_devicetable" support in the
files include/linux/mod_devicetable.h and scripts/mod/file2alias.c.
(The latter files seem to be explicitly _designed_ to get conflicts when
different subsystems work with them - that have an absolutely horrid
lack of subsystem separation!)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
lockdep annotate rcu_read_{,un}lock{,_bh} in order to catch imbalanced
usage.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Provide a check to validate that we do not hold any locks when switching
back to user-space.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The fancy mutex_lock fastpath has too many indirections to track the caller
hence all contentions are perceived to come from mutex_lock().
Avoid this by explicitly not using the fastpath code (it was disabled already
anyway).
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It is possible for the current->curr_chain_key to become inconsistent with the
current index if the chain fails to validate. The end result is that future
lock_acquire() operations may inadvertently fail to find a hit in the cache
resulting in a new node being added to the graph for every acquire.
Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Both /proc/lockdep and /proc/lock_stat output may loop infinitely.
When a read() requests an amount of data smaller than the amount of data
that the seq_file's foo_show() outputs, the output starts looping and
outputs the "stuck" element's data infinitely. There may be multiple
sequential calls to foo_start(), foo_next()/foo_show(), and foo_stop()
for a single open with sequential read of the file. The _start() does not
have to start with the 0th element and _show() might be called multiple
times in a row for the same element for a given open/read of the seq_file.
Also header output should not be happening in _start(). All output should
be in _show(), which SEQ_START_TOKEN is meant to help. Having output in
_start() may also negatively impact seq_file's seq_read() and traverse()
accounting.
Signed-off-by: Tim Pepper <lnxninja@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Al Viro <viro@ftp.linux.org.uk>
This patch make processing netlink user -> kernel messages synchronious.
This change was inspired by the talk with Alexey Kuznetsov about current
netlink messages processing. He says that he was badly wrong when introduced
asynchronious user -> kernel communication.
The call netlink_unicast is the only path to send message to the kernel
netlink socket. But, unfortunately, it is also used to send data to the
user.
Before this change the user message has been attached to the socket queue
and sk->sk_data_ready was called. The process has been blocked until all
pending messages were processed. The bad thing is that this processing
may occur in the arbitrary process context.
This patch changes nlk->data_ready callback to get 1 skb and force packet
processing right in the netlink_unicast.
Kernel -> user path in netlink_unicast remains untouched.
EINTR processing for in netlink_run_queue was changed. It forces rtnl_lock
drop, but the process remains in the cycle until the message will be fully
processed. So, there is no need to use this kludges now.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows you to create a new network namespace
using sys_clone, or sys_unshare.
As the network namespace is still experimental and under development
clone and unshare support is only made available when CONFIG_NET_NS is
selected at compile time.
As this patch introduces network namespace support into code paths
that exist when the CONFIG_NET is not selected there are a few
additions made to net_namespace.h to allow a few more functions
to be used when the networking stack is not compiled in.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Each netlink socket will live in exactly one network namespace,
this includes the controlling kernel sockets.
This patch updates all of the existing netlink protocols
to only support the initial network namespace. Request
by clients in other namespaces will get -ECONREFUSED.
As they would if the kernel did not have the support for
that netlink protocol compiled in.
As each netlink protocol is updated to be multiple network
namespace safe it can register multiple kernel sockets
to acquire a presence in the rest of the network namespaces.
The implementation in af_netlink is a simple filter implementation
at hash table insertion and hash table look up time.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As noted by Christoph Hellwig, pktgen was the only user so
it can now be removed.
[ Add missing cases caught by Adrian Bunk. -DaveM ]
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
First user will be the DCCP transport networking protocol.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hide everything in blkdev.h with CONFIG_BLOCK isn't set, and fixup
the (few) files that fail to build because they were relying on blkdev.h
pulling in extra includes for them.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
commit e5a16b1f9eec0af7cfa0830304b41c1c0833cf9f
Author: Len Brown <len.brown@intel.com>
Date: Tue Oct 2 23:44:44 2007 -0400
cpuidle: shrink diff
processor_idle.c | 440 +++++++++++++++++++++++++++++++++++++++++--
1 file changed, 429 insertions(+), 11 deletions(-)
Signed-off-by: Len Brown <len.brown@intel.com>
commit dfbb9d5aedfb18848a3e0d6f6e3e4969febb209c
Author: Len Brown <len.brown@intel.com>
Date: Wed Sep 26 02:17:55 2007 -0400
cpuidle: reduce diff size
Reduces the cpuidle processor_idle.c diff vs 2.6.22 from this
processor_idle.c | 2006 ++++++++++++++++++++++++++-----------------
1 file changed, 1219 insertions(+), 787 deletions(-)
to this:
processor_idle.c | 502 +++++++++++++++++++++++++++++++++++++++----
1 file changed, 458 insertions(+), 44 deletions(-)
...for the purpose of making the cpuilde patch less invasive
and easier to review.
no functional changes. build tested only.
Signed-off-by: Len Brown <len.brown@intel.com>
commit 889172fc915f5a7fe20f35b133cbd205ce69bf6c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Thu Sep 13 13:40:05 2007 -0700
cpuidle: Retain old ACPI policy for !CONFIG_CPU_IDLE
Retain the old policy in processor_idle, so that when CPU_IDLE is not
configured, old C-state policy will still be used. This provides a
clean gradual migration path from old ACPI policy to new cpuidle
based policy.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 9544a8181edc7ecc33b3bfd69271571f98ed08bc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Thu Sep 13 13:39:17 2007 -0700
cpuidle: Configure governors by default
Quoting Len "Do not give an option to users to shoot themselves in the foot".
Remove the configurability of ladder and menu governors as they are
needed for default policy of cpuidle. That way users will not be able to
have cpuidle without any policy loosing all C-state power savings.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 8975059a2c1e56cfe83d1bcf031bcf4cb39be743
Author: Adam Belay <abelay@novell.com>
Date: Tue Aug 21 18:27:07 2007 -0400
CPUIDLE: load ACPI properly when CPUIDLE is disabled
Change the registration return codes for when CPUIDLE
support is not compiled into the kernel. As a result, the ACPI
processor driver will load properly even if CPUIDLE is unavailable.
However, it may be possible to cleanup the ACPI processor driver further
and eliminate some dead code paths.
Signed-off-by: Adam Belay <abelay@novell.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit e0322e2b58dd1b12ec669bf84693efe0dc2414a8
Author: Adam Belay <abelay@novell.com>
Date: Tue Aug 21 18:26:06 2007 -0400
CPUIDLE: remove cpuidle_get_bm_activity()
Remove cpuidle_get_bm_activity() and updates governors
accordingly.
Signed-off-by: Adam Belay <abelay@novell.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 18a6e770d5c82ba26653e53d240caa617e09e9ab
Author: Adam Belay <abelay@novell.com>
Date: Tue Aug 21 18:25:58 2007 -0400
CPUIDLE: max_cstate fix
Currently max_cstate is limited to 0, resulting in no idle processor
power management on ACPI platforms. This patch restores the value to
the array size.
Signed-off-by: Adam Belay <abelay@novell.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 1fdc0887286179b40ce24bcdbde663172e205ef0
Author: Adam Belay <abelay@novell.com>
Date: Tue Aug 21 18:25:40 2007 -0400
CPUIDLE: handle BM detection inside the ACPI Processor driver
Update the ACPI processor driver to detect BM activity and
limit state entry depth internally, rather than exposing such
requirements to CPUIDLE. As a result, CPUIDLE can drop this
ACPI-specific interface and become more platform independent. BM
activity is now handled much more aggressively than it was in the
original implementation, so some testing coverage may be needed to
verify that this doesn't introduce any DMA buffer under-run issues.
Signed-off-by: Adam Belay <abelay@novell.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 0ef38840db666f48e3cdd2b769da676c57228dd9
Author: Adam Belay <abelay@novell.com>
Date: Tue Aug 21 18:25:14 2007 -0400
CPUIDLE: menu governor updates
Tweak the menu governor to more effectively handle non-timer
break events. Non-timer break events are detected by comparing the
actual sleep time to the expected sleep time. In future revisions, it
may be more reliable to use the timer data structures directly.
Signed-off-by: Adam Belay <abelay@novell.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit bb4d74fca63fa96cf3ace644b15ae0f12b7df5a1
Author: Adam Belay <abelay@novell.com>
Date: Tue Aug 21 18:24:40 2007 -0400
CPUIDLE: fix 'current_governor' sysfs entry
Allow the "current_governor" sysfs entry to properly handle
input terminated with '\n'.
Signed-off-by: Adam Belay <abelay@novell.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit df3c71559bb69b125f1a48971bf0d17f78bbdf47
Author: Len Brown <len.brown@intel.com>
Date: Sun Aug 12 02:00:45 2007 -0400
cpuidle: fix IA64 build (again)
Signed-off-by: Len Brown <len.brown@intel.com>
commit a02064579e3f9530fd31baae16b1fc46b5a7bca8
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Sun Aug 12 01:39:27 2007 -0400
cpuidle: Remove support for runtime changing of max_cstate
Remove support for runtime changeability of max_cstate. Drivers can use
use latency APIs.
max_cstate can still be used as a boot time option and dmi override.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 0912a44b13adf22f5e3f607d263aed23b4910d7e
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Sun Aug 12 01:39:16 2007 -0400
cpuidle: Remove ACPI cstate_limit calls from ipw2100
ipw2100 already has code to use accetable_latency interfaces to limit the
C-state. Remove the calls to acpi_set_cstate_limit and acpi_get_cstate_limit
as they are redundant.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit c649a76e76be6bff1fd770d0a775798813a3f6e0
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Sun Aug 12 01:35:39 2007 -0400
cpuidle: compile fix for pause and resume functions
Fix the compilation failure when cpuidle is not compiled in.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Adam Belay <adam.belay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 2305a5920fb8ee6ccec1c62ade05aa8351091d71
Author: Adam Belay <abelay@novell.com>
Date: Thu Jul 19 00:49:00 2007 -0400
cpuidle: re-write
Some portions have been rewritten to make the code cleaner and lighter
weight. The following is a list of changes:
1.) the state name is now included in the sysfs interface
2.) detection, hotplug, and available state modifications are handled by
CPUIDLE drivers directly
3.) the CPUIDLE idle handler is only ever installed when at least one
cpuidle_device is enabled and ready
4.) the menu governor BM code no longer overflows
5.) the sysfs attributes are now printed as unsigned integers, avoiding
negative values
6.) a variety of other small cleanups
Also, Idle drivers are no longer swappable during runtime through the
CPUIDLE sysfs inteface. On i386 and x86_64 most idle handlers (e.g.
poll, mwait, halt, etc.) don't benefit from an infrastructure that
supports multiple states, so I think using a more general case idle
handler selection mechanism would be cleaner.
Signed-off-by: Adam Belay <abelay@novell.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit df25b6b56955714e6e24b574d88d1fd11f0c3ee5
Author: Len Brown <len.brown@intel.com>
Date: Tue Jul 24 17:08:21 2007 -0400
cpuidle: fix IA64 buid
Signed-off-by: Len Brown <len.brown@intel.com>
commit fd6ada4c14488755ff7068860078c437431fbccd
Author: Adrian Bunk <bunk@stusta.de>
Date: Mon Jul 9 11:33:13 2007 -0700
cpuidle: static
make cpuidle_replace_governor() static
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit c1d4a2cebcadf2429c0c72e1d29aa2a9684c32e0
Author: Adrian Bunk <bunk@stusta.de>
Date: Tue Jul 3 00:54:40 2007 -0400
cpuidle: static
This patch makes the needlessly global struct menu_governor static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit dbf8780c6e8d572c2c273da97ed1cca7608fd999
Author: Andrew Morton <akpm@linux-foundation.org>
Date: Tue Jul 3 00:49:14 2007 -0400
export symbol tick_nohz_get_sleep_length
ERROR: "tick_nohz_get_sleep_length" [drivers/cpuidle/governors/menu.ko] undefined!
ERROR: "tick_nohz_get_idle_jiffies" [drivers/cpuidle/governors/menu.ko] undefined!
And please be sure to get your changes to core kernel suitably reviewed.
Cc: Adam Belay <abelay@novell.com>
Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 29f0e248e7017be15f99febf9143a2cef00b2961
Author: Andrew Morton <akpm@linux-foundation.org>
Date: Tue Jul 3 00:43:04 2007 -0400
tick.h needs hrtimer.h
It uses hrtimers.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit e40cede7d63a029e92712a3fe02faee60cc38fb4
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Jul 3 00:40:34 2007 -0400
cpuidle: first round of documentation updates
Documentation changes based on Pavel's feedback.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 83b42be2efece386976507555c29e7773a0dfcd1
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Jul 3 00:39:25 2007 -0400
cpuidle: add rating to the governors and pick the one with highest rating by default
Introduce a governor rating scheme to pick the right governor by default.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit d2a74b8c5e8f22def4709330d4bfc4a29209b71c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Jul 3 00:38:08 2007 -0400
cpuidle: make cpuidle sysfs driver governor switch off by default
Make default cpuidle sysfs to show current_governor and current_driver in
read-only mode. More elaborate available_governors and available_drivers with
writeable current_governor and current_driver interface only appear with
"cpuidle_sysfs_switch" boot parameter.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 1f60a0e80bf83cf6b55c8845bbe5596ed8f6307b
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Jul 3 00:37:00 2007 -0400
cpuidle: menu governor: change the early break condition
Change the C-state early break out algorithm in menu governor.
We only look at early breakouts that result in wakeups shorter than idle
state's target_residency. If such a breakout is frequent enough, eliminate
the particular idle state upto a timeout period.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 45a42095cf64b003b4a69be3ce7f434f97d7af51
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Jul 3 00:35:38 2007 -0400
cpuidle: fix uninitialized variable in sysfs routine
Fix the uninitialized usage of ret.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 80dca7cdba3e6ee13eae277660873ab9584eb3be
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Jul 3 00:34:16 2007 -0400
cpuidle: reenable /proc/acpi//power interface for the time being
Keep /proc/acpi/processor/CPU*/power around for a while as powertop depends
on it. It will be marked deprecated and removed in future. powertop can use
cpuidle interfaces instead.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 589c37c2646c5e3813a51255a5ee1159cb4c33fc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Jul 3 00:32:37 2007 -0400
cpuidle: menu governor and hrtimer compile fix
Compile fix for menu governor.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 0ba80bd9ab3ed304cb4f19b722e4cc6740588b5e
Author: Len Brown <len.brown@intel.com>
Date: Thu May 31 22:51:43 2007 -0400
cpuidle: build fix - cpuidle vs ipw2100 module
ERROR: "acpi_set_cstate_limit" [drivers/net/wireless/ipw2100.ko] undefined!
Signed-off-by: Len Brown <len.brown@intel.com>
commit d7d8fa7f96a7f7682be7c6cc0cc53fa7a18c3b58
Author: Adam Belay <abelay@novell.com>
Date: Sat Mar 24 03:47:07 2007 -0400
cpuidle: add the 'menu' governor
Here is my first take at implementing an idle PM governor that takes
full advantage of NO_HZ. I call it the 'menu' governor because it
considers the full list of idle states before each entry.
I've kept the implementation fairly simple. It attempts to guess the
next residency time and then chooses a state that would meet at least
the break-even point between power savings and entry cost. To this end,
it selects the deepest idle state that satisfies the following
constraints:
1. If the idle time elapsed since bus master activity was detected
is below a threshold (currently 20 ms), then limit the selection
to C2-type or above.
2. Do not choose a state with a break-even residency that exceeds
the expected time remaining until the next timer interrupt.
3. Do not choose a state with a break-even residency that exceeds
the elapsed time between the last pair of break events,
excluding timer interrupts.
This governor has an advantage over "ladder" governor because it
proactively checks how much time remains until the next timer interrupt
using the tick infrastructure. Also, it handles device interrupt
activity more intelligently by not including timer interrupts in break
event calculations. Finally, it doesn't make policy decisions using the
number of state entries, which can have variable residency times (NO_HZ
makes these potentially very large), and instead only considers sleep
time deltas.
The menu governor can be selected during runtime using the cpuidle sysfs
interface like so:
"echo "menu" > /sys/devices/system/cpu/cpuidle/current_governor"
Signed-off-by: Adam Belay <abelay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit a4bec7e65aa3b7488b879d971651cc99a6c410fe
Author: Adam Belay <abelay@novell.com>
Date: Sat Mar 24 03:47:03 2007 -0400
cpuidle: export time until next timer interrupt using NO_HZ
Expose information about the time remaining until the next
timer interrupt expires by utilizing the dynticks infrastructure.
Also modify the main idle loop to allow dynticks to handle
non-interrupt break events (e.g. DMA). Finally, expose sleep ticks
information to external code. Thomas Gleixner is responsible for much
of the code in this patch. However, I've made some additional changes,
so I'm probably responsible if there are any bugs or oversights :)
Signed-off-by: Adam Belay <abelay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 2929d8996fbc77f41a5ff86bb67cdde3ca7d2d72
Author: Adam Belay <abelay@novell.com>
Date: Sat Mar 24 03:46:58 2007 -0400
cpuidle: governor API changes
This patch prepares cpuidle for the menu governor. It adds an optional
stage after idle state entry to give the governor an opportunity to
check why the state was exited. Also it makes sure the idle loop
returns after each state entry, allowing the appropriate dynticks code
to run.
Signed-off-by: Adam Belay <abelay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 3a7fd42f9825c3b03e364ca59baa751bb350775f
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date: Thu Apr 26 00:03:59 2007 -0700
cpuidle: hang fix
Prevent hang on x86-64, when ACPI processor driver is added as a module on
a system that does not support C-states.
x86-64 expects all idle handlers to enable interrupts before returning from
idle handler. This is due to enter_idle(), exit_idle() races. Make
cpuidle_idle_call() confirm to this when there is no pm_idle_old.
Also, cpuidle look at the return values of attch_driver() and set
current_driver to NULL if attach fails on all CPUs.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 4893339a142afbd5b7c01ffadfd53d14746e858e
Author: Shaohua Li <shaohua.li@intel.com>
Date: Thu Apr 26 10:40:09 2007 +0800
cpuidle: add support for max_cstate limit
With CPUIDLE framework, the max_cstate (to limit max cpu c-state)
parameter is ingored. Some systems require it to ignore C2/C3
and some drivers like ipw require it too.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 43bbbbe1cb998cbd2df656f55bb3bfe30f30e7d1
Author: Shaohua Li <shaohua.li@intel.com>
Date: Thu Apr 26 10:40:13 2007 +0800
cpuidle: add cpuidle_fore_redetect_devices API
add cpuidle_force_redetect_devices API,
which forces all CPU redetect idle states.
Next patch will use it.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit d1edadd608f24836def5ec483d2edccfb37b1d19
Author: Shaohua Li <shaohua.li@intel.com>
Date: Thu Apr 26 10:40:01 2007 +0800
cpuidle: fix sysfs related issue
Fix the cpuidle sysfs issue.
a. make kobject dynamicaly allocated
b. fixed sysfs init issue to avoid suspend/resume issue
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 7169a5cc0d67b263978859672e86c13c23a5570d
Author: Randy Dunlap <randy.dunlap@oracle.com>
Date: Wed Mar 28 22:52:53 2007 -0400
cpuidle: 1-bit field must be unsigned
A 1-bit bitfield has no room for a sign bit.
drivers/cpuidle/governors/ladder.c:54:16: error: dubious bitfield without explicit `signed' or `unsigned'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 4658620158dc2fbd9e4bcb213c5b6fb5d05ba7d4
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Wed Mar 28 22:52:41 2007 -0400
cpuidle: fix boot hang
Patch for cpuidle boot hang reported by Larry Finger here.
http://www.ussg.iu.edu/hypermail/linux/kernel/0703.2/2025.html
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Larry Finger <larry.finger@lwfinger.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit c17e168aa6e5fe3851baaae8df2fbc1cf11443a9
Author: Len Brown <len.brown@intel.com>
Date: Wed Mar 7 04:37:53 2007 -0500
cpuidle: ladder does not depend on ACPI
build fix for CONFIG_ACPI=n
In file included from drivers/cpuidle/governors/ladder.c:21:
include/acpi/processor.h:88: error: expected specifier-qualifier-list before âacpi_integerâ
include/acpi/processor.h:106: error: expected specifier-qualifier-list before âacpi_integerâ
include/acpi/processor.h:168: error: expected specifier-qualifier-list before âacpi_handleâ
Signed-off-by: Len Brown <len.brown@intel.com>
commit 8c91d958246bde68db0c3f0c57b535962ce861cb
Author: Adrian Bunk <bunk@stusta.de>
Date: Tue Mar 6 02:29:40 2007 -0800
cpuidle: make code static
This patch makes the following needlessly global code static:
- driver.c: __cpuidle_find_driver()
- governor.c: __cpuidle_find_governor()
- ladder.c: struct ladder_governor
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Adam Belay <abelay@novell.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 0c39dc3187094c72c33ab65a64d2017b21f372d2
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Wed Mar 7 02:38:22 2007 -0500
cpu_idle: fix build break
This patch fixes a build breakage with !CONFIG_HOTPLUG_CPU and
CONFIG_CPU_IDLE.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 8112e3b115659b07df340ef170515799c0105f82
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Tue Mar 6 02:29:39 2007 -0800
cpuidle: build fix for !CPU_IDLE
Fix the compile issues when CPU_IDLE is not configured.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Adam Belay <abelay@novell.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 1eb4431e9599cd25e0d9872f3c2c8986821839dd
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Thu Feb 22 13:54:57 2007 -0800
cpuidle take2: Basic documentation for cpuidle
Documentation for cpuidle infrastructure
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Adam Belay <abelay@novell.com>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit ef5f15a8b79123a047285ec2e3899108661df779
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Thu Feb 22 13:54:03 2007 -0800
cpuidle take2: Hookup ACPI C-states driver with cpuidle
Hookup ACPI C-states onto generic cpuidle infrastructure.
drivers/acpi/procesor_idle.c is now a ACPI C-states driver that registers as
a driver in cpuidle infrastructure and the policy part is removed from
drivers/acpi/processor_idle.c. We use governor in cpuidle instead.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Adam Belay <abelay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 987196fa82d4db52c407e8c9d5dec884ba602183
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Thu Feb 22 13:52:57 2007 -0800
cpuidle take2: Core cpuidle infrastructure
Announcing 'cpuidle', a new CPU power management infrastructure to manage
idle CPUs in a clean and efficient manner.
cpuidle separates out the drivers that can provide support for multiple types
of idle states and policy governors that decide on what idle state to use
at run time.
A cpuidle driver can support multiple idle states based on parameters like
varying power consumption, wakeup latency, etc (ACPI C-states for example).
A cpuidle governor can be usage model specific (laptop, server,
laptop on battery etc).
Main advantage of the infrastructure being, it allows independent development
of drivers and governors and allows for better CPU power management.
A huge thanks to Adam Belay and Shaohua Li who were part of this mini-project
since its beginning and are greatly responsible for this patchset.
This patch:
Core cpuidle infrastructure.
Introduces a new abstraction layer for cpuidle:
* which manages drivers that can support multiple idles states. Drivers
can be generic or particular to specific hardware/platform
* allows pluging in multiple policy governors that can take idle state policy
decision
* The core also has a set of sysfs interfaces with which administrato can know
about supported drivers and governors and switch them at run time.
Signed-off-by: Adam Belay <abelay@novell.com>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This will allow rpc.gssd to use inotify instead of dnotify in order to
locate new rpc upcall pipes.
This also requires the exporting of __audit_inode_child(), which is used by
fsnotify_create() and fsnotify_mkdir(). Ccing David Woodhouse.
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Async signals should not be reported as sent by current in audit log. As
it is, we call audit_signal_info() too early in check_kill_permission().
Note that check_kill_permission() has that test already - it needs to know
if it should apply current-based permission checks. So the solution is to
move the call of audit_signal_info() between those.
Bogosity in question is easily reproduced - add a rule watching for e.g.
kill(2) from specific process (so that audit_signal_info() would not
short-circuit to nothing), say load_policy, watch the bogus OBJ_PID entry
in audit logs claiming that write(2) on selinuxfs file issued by
load_policy(8) had somehow managed to send a signal to syslogd...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Steve Grubb <sgrubb@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When using /proc/timer_stats on ppc64 I noticed the events/sec field wasnt
accurate. Sometimes the integer part was incorrect due to rounding (we
werent taking the fractional seconds into consideration).
The fraction part is also wrong, we need to pad the printf statement and
take the bottom three digits of 1000 times the value.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Calling handle_futex_death in exit_robust_list for the different robust
mutexes of a thread basically frees the mutex. Another thread might grab
the lock immediately which updates the next pointer of the mutex.
fetch_robust_entry over the next pointer might therefore branch into the
robust mutex list of a different thread. This can cause two problems: 1)
some mutexes held by the dead thread are not getting freed and 2) some
mutexs held by a different thread are freed.
The next point need to be read before calling handle_futex_death.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need to disable all CPUs other than the boot CPU (usually 0) before
attempting to power-off modern SMP machines. This fixes the
hang-on-poweroff issue on my MythTV SMP box, and also on Thomas Gleixner's
new toybox.
Signed-off-by: Mark Lord <mlord@pobox.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In a desparate attempt to fix the suspend/resume problem on Andrews
VAIO I added a workaround which enforced the broadcast of the oneshot
timer on resume. This was actually resolving the problem on the VAIO
but was just a stupid workaround, which was not tackling the root
cause: the assignement of lower idle C-States in the ACPI processor_idle
code. The cpuidle patches, which utilize the dynamic tick feature and
go faster into deeper C-states exposed the problem again. The correct
solution is the previous patch, which prevents lower C-states across
the suspend/resume.
Remove the enforcement code, including the conditional broadcast timer
arming, which helped to pamper over the real problem for quite a time.
The oneshot broadcast flag for the cpu, which runs the resume code can
never be set at the time when this code is executed. It only gets set,
when the CPU is entering a lower idle C-State.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This simplifies signalfd code, by avoiding it to remain attached to the
sighand during its lifetime.
In this way, the signalfd remain attached to the sighand only during
poll(2) (and select and epoll) and read(2). This also allows to remove
all the custom "tsk == current" checks in kernel/signal.c, since
dequeue_signal() will only be called by "current".
I think this is also what Ben was suggesting time ago.
The external effect of this, is that a thread can extract only its own
private signals and the group ones. I think this is an acceptable
behaviour, in that those are the signals the thread would be able to
fetch w/out signalfd.
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When using rt_mutex, a NULL pointer dereference is occurred at
enqueue_task_rt. Here is a scenario;
1) there are two threads, the thread A is fair_sched_class and
thread B is rt_sched_class.
2) Thread A is boosted up to rt_sched_class, because the thread A
has a rt_mutex lock and the thread B is waiting the lock.
3) At this time, when thread A create a new thread C, the thread
C has a rt_sched_class.
4) When doing wake_up_new_task() for the thread C, the priority
of the thread C is out of the RT priority range, because the
normal priority of thread A is not the RT priority. It makes
data corruption by overflowing the rt_prio_array.
The new thread C should be fair_sched_class.
The new thread should be valid scheduler class before queuing.
This patch fixes to set the suitable scheduler class.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
add /proc/sys/kernel/sched_compat_yield to make sys_sched_yield()
more agressive, by moving the yielding task to the last position
in the rbtree.
with sched_compat_yield=0:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2539 mingo 20 0 1576 252 204 R 50 0.0 0:02.03 loop_yield
2541 mingo 20 0 1576 244 196 R 50 0.0 0:02.05 loop
with sched_compat_yield=1:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2584 mingo 20 0 1576 248 196 R 99 0.0 0:52.45 loop
2582 mingo 20 0 1576 256 204 R 0 0.0 0:00.00 loop_yield
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
It turned out, that the user namespace is released during the do_exit() in
exit_task_namespaces(), but the struct user_struct is released only during the
put_task_struct(), i.e. MUCH later.
On debug kernels with poisoned slabs this will cause the oops in
uid_hash_remove() because the head of the chain, which resides inside the
struct user_namespace, will be already freed and poisoned.
Since the uid hash itself is required only when someone can search it, i.e.
when the namespace is alive, we can safely unhash all the user_struct-s from
it during the namespace exiting. The subsequent free_uid() will complete the
user_struct destruction.
For example simple program
#include <sched.h>
char stack[2 * 1024 * 1024];
int f(void *foo)
{
return 0;
}
int main(void)
{
clone(f, stack + 1 * 1024 * 1024, 0x10000000, 0);
return 0;
}
run on kernel with CONFIG_USER_NS turned on will oops the
kernel immediately.
This was spotted during OpenVZ kernel testing.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Acked-by: "Serge E. Hallyn" <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Surprisingly, but (spotted by Alexey Dobriyan) the uid hash still uses
list_heads, thus occupying twice as much place as it could. Convert it to
hlist_heads.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
struct utsname is copied from master one without any exclusion.
Here is sample output from one proggie doing
sethostname("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
sethostname("bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb");
and another
clone(,, CLONE_NEWUTS, ...)
uname()
hostname = 'aaaaaaaaaaaaaaaaaaaaaaaaabbbbb'
hostname = 'bbbaaaaaaaaaaaaaaaaaaaaaaaaaaa'
hostname = 'aaaaaaaabbbbbbbbbbbbbbbbbbbbbb'
hostname = 'aaaaaaaaaaaaaaaaaaaaaaaaaabbbb'
hostname = 'aaaaaaaaaaaaaaaaaaaaaaaaaaaabb'
hostname = 'aaabbbbbbbbbbbbbbbbbbbbbbbbbbb'
hostname = 'bbbbbbbbbbbbbbbbaaaaaaaaaaaaaa'
Hostname is sometimes corrupted.
Yes, even _the_ simplest namespace activity had bug in it. :-(
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Taking a cpu offline removes the cpu from the online mask before the
CPU_DEAD notification is done. The clock events layer does the cleanup
of the dead CPU from the CPU_DEAD notifier chain. tick_do_timer_cpu is
used to avoid xtime lock contention by assigning the task of jiffies
xtime updates to one CPU. If a CPU is taken offline, then this
assignment becomes stale. This went unnoticed because most of the time
the offline CPU went dead before the online CPU reached __cpu_die(),
where the CPU_DEAD state is checked. In the case that the offline CPU did
not reach the DEAD state before we reach __cpu_die(), the code in there
goes to sleep for 100ms. Due to the stale time update assignment, the
system is stuck forever.
Take the assignment away when a cpu is not longer in the cpu_online_mask.
We do this in the last call to tick_nohz_stop_sched_tick() when the offline
CPU is on the way to the final play_dead() idle entry.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When a cpu goes offline it is removed from the broadcast masks. If the
mask becomes empty the code shuts down the broadcast device. This is
wrong, because the broadcast device needs to be ready for the online
cpu going idle (into a c-state, which stops the local apic timer).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The jinxed VAIO refuses to resume without hitting keys on the keyboard
when this is not enforced. It is unclear why the cpu ends up in a lower
C State without notifying the clock events layer, but enforcing the
oneshot broadcast here is safe.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Timekeeping resume adjusts xtime by adding the slept time in seconds and
resets the reference value of the clock source (clock->cycle_last).
clock->cycle last is used to calculate the delta between the last xtime
update and the readout of the clock source in __get_nsec_offset(). xtime
plus the offset is the current time. The resume code ignores the delta
which had already elapsed between the last xtime update and the actual
time of suspend. If the suspend time is short, then we can see time
going backwards on resume.
Suspend:
offs_s = clock->read() - clock->cycle_last;
now = xtime + offs_s;
timekeeping_suspend_time = read_rtc();
Resume:
sleep_time = read_rtc() - timekeeping_suspend_time;
xtime.tv_sec += sleep_time;
clock->cycle_last = clock->read();
offs_r = clock->read() - clock->cycle_last;
now = xtime + offs_r;
if sleep_time_seconds == 0 and offs_r < offs_s, then time goes
backwards.
Fix this by storing the offset from the last xtime update and add it to
xtime during resume, when we reset clock->cycle_last:
sleep_time = read_rtc() - timekeeping_suspend_time;
xtime.tv_sec += sleep_time;
xtime += offs_s; /* Fixup xtime offset at suspend time */
clock->cycle_last = clock->read();
offs_r = clock->read() - clock->cycle_last;
now = xtime + offs_r;
Thanks to Marcelo for tracking this down on the OLPC and providing the
necessary details to analyze the root cause.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Tosatti <marcelo@kvack.org>
Lockdep complains about the access of rtc in timekeeping_suspend
inside the interrupt disabled region of the write locked xtime lock.
Move the access outside.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Seems to me that this timer will only get started on platforms that say
they don't want it?
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Gabriel Paubert <paubert@iram.es>
Cc: Zachary Amsden <zach@vmware.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The semantics of call_usermodehelper_pipe() used to be that it would fork
the helper, and wait for the kernel thread to be started. This was
implemented by setting sub_info.wait to 0 (implicitly), and doing a
wait_for_completion().
As part of the cleanup done in 0ab4dc9227,
call_usermodehelper_pipe() was changed to pass 1 as the value for wait to
call_usermodehelper_exec().
This is equivalent to setting sub_info.wait to 1, which is a change from
the previous behaviour. Using 1 instead of 0 causes
__call_usermodehelper() to start the kernel thread running
wait_for_helper(), rather than directly calling ____call_usermodehelper().
The end result is that the calling kernel code blocks until the user mode
helper finishes. As the helper is expecting input on stdin, and now no one
is writing anything, everything locks up (observed in do_coredump).
The fix is to change the 1 to UMH_WAIT_EXEC (aka 0), indicating that we
want to wait for the kernel thread to be started, but not for the helper to
finish.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The futex list traversal on the compat side appears to have
a bug.
It's loop termination condition compares:
while (compat_ptr(uentry) != &head->list)
But that can't be right because "uentry" has the special
"pi" indicator bit still potentially set at bit 0. This
is cleared by fetch_robust_entry() into the "entry"
return value.
What this seems to mean is that the list won't terminate
when list iteration gets back to the the head. And we'll
also process the list head like a normal entry, which could
cause all kinds of problems.
So we should check for equality with "entry". That pointer
is of the non-compat type so we have to do a little casting
to keep the compiler and sparse happy.
The same problem can in theory occur with the 'pending'
variable, although that has not been reported from users
so far.
Based on the original patch from David Miller.
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When PTRACE_SYSCALL was used and then PTRACE_DETACH is used, the
TIF_SYSCALL_TRACE flag is left set on the formerly-traced task. This
means that when a new tracer comes along and does PTRACE_ATTACH, it's
possible he gets a syscall tracing stop even though he's never used
PTRACE_SYSCALL. This happens if the task was in the middle of a system
call when the second PTRACE_ATTACH was done. The symptom is an
unexpected SIGTRAP when the tracer thinks that only SIGSTOP should have
been provoked by his ptrace calls so far.
A few machines already fixed this in ptrace_disable (i386, ia64, m68k).
But all other machines do not, and still have this bug. On x86_64, this
constitutes a regression in IA32 compatibility support.
Since all machines now use TIF_SYSCALL_TRACE for this, I put the
clearing of TIF_SYSCALL_TRACE in the generic ptrace_detach code rather
than adding it to every other machine's ptrace_disable.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fix ideal_runtime:
- do not scale it using niced_granularity()
it is against sum_exec_delta, so its wall-time, not fair-time.
- move the whole check into __check_preempt_curr_fair()
so that wakeup preemption can also benefit from the new logic.
this also results in code size reduction:
text data bss dec hex filename
13391 228 1204 14823 39e7 sched.o.before
13369 228 1204 14801 39d1 sched.o.after
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Second preparatory patch for fix-ideal runtime:
Mark prev_sum_exec_runtime at the beginning of our run, the same spot
that adds our wait period to wait_runtime. This seems a more natural
location to do this, and it also reduces the code a bit:
text data bss dec hex filename
13397 228 1204 14829 39ed sched.o.before
13391 228 1204 14823 39e7 sched.o.after
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Preparatory patch for fix-ideal-runtime:
simplify __check_preempt_curr_fair(): get rid of the integer return.
text data bss dec hex filename
13404 228 1204 14836 39f4 sched.o.before
13393 228 1204 14825 39e9 sched.o.after
functionality is unchanged.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
the cfs_rq->wait_runtime debug/statistics counter was not maintained
properly - fix this.
this also removes some code:
text data bss dec hex filename
13420 228 1204 14852 3a04 sched.o.before
13404 228 1204 14836 39f4 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
fix niced_granularity(). This resulted in under-scheduling for
CPU-bound negative nice level tasks (and this in turn caused
higher than necessary latencies in nice-0 tasks).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
First fix the check
if (*imbalance + SCHED_LOAD_SCALE_FUZZ < busiest_load_per_task)
with this
if (*imbalance < busiest_load_per_task)
As the current check is always false for nice 0 tasks (as
SCHED_LOAD_SCALE_FUZZ is same as busiest_load_per_task for nice 0
tasks).
With the above change, imbalance was getting reset to 0 in the corner
case condition, making the FUZZ logic fail. Fix it by not corrupting the
imbalance and change the imbalance, only when it finds that the HT/MC
optimization is needed.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
sched: clean up task_new_fair()
sched: small schedstat fix
sched: fix wait_start_fair condition in update_stats_wait_end()
sched: call update_curr() in task_tick_fair()
sched: make the scheduler converge to the ideal latency
sched: fix sleeper bonus limit
Spotted by taoyue <yue.tao@windriver.com> and Jeremy Katz <jeremy.katz@windriver.com>.
collect_signal: sigqueue_free:
list_del_init(&first->list);
if (!list_empty(&q->list)) {
// not taken
}
q->flags &= ~SIGQUEUE_PREALLOC;
__sigqueue_free(first); __sigqueue_free(q);
Now, __sigqueue_free() is called twice on the same "struct sigqueue" with the
obviously bad implications.
In particular, this double free breaks the array_cache->avail logic, so the
same sigqueue could be "allocated" twice, and the bug can manifest itself via
the "impossible" BUG_ON(!SIGQUEUE_PREALLOC) in sigqueue_free/send_sigqueue.
Hopefully this can explain these mysterious bug-reports, see
http://marc.info/?t=118766926500003http://marc.info/?t=118466273000005
Alexey Dobriyan reports this patch makes the difference for the testcase, but
nobody has an access to the application which opened the problems originally.
Also, this patch removes tasklist lock/unlock, ->siglock is enough.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: taoyue <yue.tao@windriver.com>
Cc: Jeremy Katz <jeremy.katz@windriver.com>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Roland McGrath <roland@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mariusz Kozlowski reported lockdep's warning:
> =================================
> [ INFO: inconsistent lock state ]
> 2.6.23-rc2-mm1 #7
> ---------------------------------
> inconsistent {in-hardirq-W} -> {hardirq-on-W} usage.
> ifconfig/5492 [HC0[0]:SC0[0]:HE1:SE1] takes:
> (&tp->lock){+...}, at: [<de8706e0>] rtl8139_interrupt+0x27/0x46b [8139too]
> {in-hardirq-W} state was registered at:
> [<c0138eeb>] __lock_acquire+0x949/0x11ac
> [<c01397e7>] lock_acquire+0x99/0xb2
> [<c0452ff3>] _spin_lock+0x35/0x42
> [<de8706e0>] rtl8139_interrupt+0x27/0x46b [8139too]
> [<c0147a5d>] handle_IRQ_event+0x28/0x59
> [<c01493ca>] handle_level_irq+0xad/0x10b
> [<c0105a13>] do_IRQ+0x93/0xd0
> [<c010441e>] common_interrupt+0x2e/0x34
...
> other info that might help us debug this:
> 1 lock held by ifconfig/5492:
> #0: (rtnl_mutex){--..}, at: [<c0451778>] mutex_lock+0x1c/0x1f
>
> stack backtrace:
...
> [<c0452ff3>] _spin_lock+0x35/0x42
> [<de8706e0>] rtl8139_interrupt+0x27/0x46b [8139too]
> [<c01480fd>] free_irq+0x11b/0x146
> [<de871d59>] rtl8139_close+0x8a/0x14a [8139too]
> [<c03bde63>] dev_close+0x57/0x74
...
This shows that a driver's irq handler was running both in hard interrupt
and process contexts with irqs enabled. The latter was done during
free_irq() call and was possible only with CONFIG_DEBUG_SHIRQ enabled.
This was fixed by another patch.
But similar problem is possible with request_irq(): any locks taken from
irq handler could be vulnerable - especially with soft interrupts. This
patch fixes it by disabling local interrupts during handler's run. (It
seems, disabling softirqs should be enough, but it needs more checking
on possible races or other special cases).
Reported-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dependencies of CONFIG_SUSPEND and CONFIG_HIBERNATION introduced by commit
296699de6b "Introduce CONFIG_SUSPEND for
suspend-to-Ram and standby" are incorrect, as they don't cover the facts that
(1) not all architectures support suspend and (2) SMP hibernation is only
possible on X86 and PPC64 (if CONFIG_PPC64_SWSUSP is set).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Spotted by Marcin Kowalczyk <qrczak@knm.org.pl>.
sys_setpgid(child) fails if the child was forked by sub-thread.
Fix the "is it our child" check. The previous commit
ee0acf90d3 was not complete.
(this patch asks for the new same_thread_group() helper, but mainline doesn't
have it yet).
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: <stable@kernel.org>
Tested-by: "Marcin 'Qrczak' Kowalczyk" <qrczak@knm.org.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
taskstats.ac_exitcode is assigned to task_struct.exit_code in bacct_add_tsk()
through the following kernel function calls:
do_exit()
taskstats_exit()
fill_pid()
bacct_add_tsk()
The problem is that in do_exit(), task_struct.exit_code is set to 'code' only
after taskstats_exit() has been called. So we need to move the assignment
before taskstats_exit().
Signed-off-by: Jonathan Lim <jlim@sgi.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cleanup: we have the 'se' and 'curr' entity-pointers already,
no need to use p->se and current->se.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
small schedstat fix: the cfs_rq->wait_runtime 'sum of all runtimes'
statistics counters missed newly forked tasks and thus had a constant
negative skew. Fix this.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Peter Zijlstra noticed the following bug in SCHED_FEAT_SKIP_INITIAL (which
is disabled by default at the moment): it relies on se.wait_start_fair
being 0 while update_stats_wait_end() did not recognize a 0 value,
so instead of 'skipping' the initial interval we gave the new child
a maximum boost of +runtime-limit ...
(No impact on the default kernel, but nice to fix for completeness.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
update the fair-clock before using it for the key value.
[ mingo@elte.hu: small cleanups. ]
Signed-off-by: Ting Yang <tingy@cs.umass.edu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
de-HZ-ification of the granularity defaults unearthed a pre-existing
property of CFS: while it correctly converges to the granularity goal,
it does not prevent run-time fluctuations in the range of
[-gran ... 0 ... +gran].
With the increase of the granularity due to the removal of HZ
dependencies, this becomes visible in chew-max output (with 5 tasks
running):
out: 28 . 27. 32 | flu: 0 . 0 | ran: 9 . 13 | per: 37 . 40
out: 27 . 27. 32 | flu: 0 . 0 | ran: 17 . 13 | per: 44 . 40
out: 27 . 27. 32 | flu: 0 . 0 | ran: 9 . 13 | per: 36 . 40
out: 29 . 27. 32 | flu: 2 . 0 | ran: 17 . 13 | per: 46 . 40
out: 28 . 27. 32 | flu: 0 . 0 | ran: 9 . 13 | per: 37 . 40
out: 29 . 27. 32 | flu: 0 . 0 | ran: 18 . 13 | per: 47 . 40
out: 28 . 27. 32 | flu: 0 . 0 | ran: 9 . 13 | per: 37 . 40
average slice is the ideal 13 msecs and the period is picture-perfect 40
msecs. But the 'ran' field fluctuates around 13.33 msecs and there's no
mechanism in CFS to keep that from happening: it's a perfectly valid
solution that CFS finds.
to fix this we add a granularity/preemption rule that knows about
the "target latency", which makes tasks that run longer than the ideal
latency run a bit less. The simplest approach is to simply decrease the
preemption granularity when a task overruns its ideal latency. For this
we have to track how much the task executed since its last preemption.
( this adds a new field to task_struct, but we can eliminate that
overhead in 2.6.24 by putting all the scheduler timestamps into an
anonymous union. )
with this change in place, chew-max output is fluctuation-less all
around:
out: 28 . 27. 39 | flu: 0 . 2 | ran: 13 . 13 | per: 41 . 40
out: 28 . 27. 39 | flu: 0 . 2 | ran: 13 . 13 | per: 41 . 40
out: 28 . 27. 39 | flu: 0 . 2 | ran: 13 . 13 | per: 41 . 40
out: 28 . 27. 39 | flu: 0 . 2 | ran: 13 . 13 | per: 41 . 40
out: 28 . 27. 39 | flu: 0 . 1 | ran: 13 . 13 | per: 41 . 40
out: 28 . 27. 39 | flu: 0 . 1 | ran: 13 . 13 | per: 41 . 40
this patch has no impact on any fastpath or on any globally observable
scheduling property. (unless you have sharp enough eyes to see
millisecond-level ruckles in glxgears smoothness :-)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
There is an Amarok song switch time increase (regression) under
hefty load.
What is happening is that sleeper_bonus is never consumed, and only
rarely goes below runtime_limit, so for the most part, Amarok isn't
getting any bonus at all. We're keeping sleeper_bonus right at
runtime_limit (sched_latency == sched_runtime_limit == 40ms) forever, ie
we don't consume if we're lower that that, and don't add if we're above
it. One Amarok thread waking (or anybody else) will push us past the
threshold, so the next thread waking gets nada, but will reap pain from
the previous thread waking until we drop back to runtime_limit. It
looks to me like under load, some random task gets a bonus, and
everybody else pays, whether deserving or not.
This diff fixed the regression for me at any load rate.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Fix bogus DEBUG_PREEMPT warning on x86_64, when cpu brought online after
bootup: current_is_keventd is right to note its use of smp_processor_id
is preempt-safe, but should use raw_smp_processor_id to avoid the warning.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
runtime limit and wakeup granularity used to be a function of
granularity and that was incorrect changed to sched_latency.
Fix this to make wakeup granularity a function of min-granularity,
and the runtime limit equal to latency.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
due to adaptive granularity scheduling the role of sched_granularity
has changed to "minimum granularity", so rename the variable (and the
tunable) accordingly.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Instead of specifying the preemption granularity, specify the wanted
latency. By fixing the granlarity to a constany the wakeup latency
it a function of the number of running tasks on the rq.
Invert this relation.
sysctl_sched_granularity becomes a minimum for the dynamic granularity
computed from the new sysctl_sched_latency.
Then use this latency to do more intelligent granularity decisions: if
there are fewer tasks running then we can schedule coarser. This helps
performance while still always keeping the latency target.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Make the lockdep sysctls not depend on CONFIG_SCHED_DEBUG.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix task startup penalty miscalculation: sysctl_sched_granularity is
unsigned int and wait_runtime is long so we first have to convert it
to long before turning it negative ...
Signed-off-by: Ingo Molnar <mingo@elte.hu>
current code:
delta = calc_delta_mine(delta_exec, curr->load.weight, lw);
delta = min((u64)delta, cfs_rq->sleeper_bonus);
Notice that this calc_delta_mine() line is exactly delta_mine, which
gives:
delta = min((u64)delta_mine, cfs_rq->sleeper_bonus);
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
current code:
delta = min(cfs_rq->sleeper_bonus, (u64)delta_exec);
delta = calc_delta_mine(delta, curr->load.weight, lw);
delta = min((u64)delta, cfs_rq->sleeper_bonus);
drop the first min(), because we clip against sleeper_bonus in the 3rd line
again. That gives:
delta = calc_delta_mine(delta_exec, curr->load.weight, lw);
delta = min((u64)delta, cfs_rq->sleeper_bonus);
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
make the bonus balance more consistent: do not hand out a bonus if
there's too much in flight already, and only deduct as much from a
runner as it has the capacity. This makes the bonus engine a zero-sum
game (as intended).
this also simplifies the code:
text data bss dec hex filename
34770 2998 24 37792 93a0 sched.o.before
34749 2998 24 37771 938b sched.o.after
and it also avoids overscheduling in sleep-happy workloads like
hackbench.c.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mitchell Erblich suggested a quality-of-implementation change to
not requeue SCHED_RR tasks if there's only a single task on the
runqueue, by checking for rq->nr_running == 1.
provide a more efficient implementation of that, to check that
particular RT priority-queue only.
[ From: mingo@elte.hu ]
Also first requeue the task then set need_resched - results in slightly
better machine-instruction ordering. Also clean up the code a bit.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove HZ dependency from the granularity default. Use 10 msec for
the base granularity, 1 msec for wakeup granularity and 25 msec for
batch wakeup granularity. (These defaults are close to the values
that the default HZ=250 setting got previously, and thus it's the
most common setting.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
when I built with CONFIG_FAIR_GROUP_SCHED=y, I need the following change
to make things right.
[ From: mingo@elte.hu ]
this config option is not upstream-configurable right now but lets fix
this for completeness.
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6:
sysfs: don't warn on removal of a nonexistent binary file
HOWTO: latest lxr url address changed
HOWTO: korean translation of Documentation/HOWTO
Fix Off-by-one in /sys/module/*/refcnt
sysfs: fix locking in sysfs_lookup() and sysfs_rename_dir()
Michael Gerdau reported reniced task CPU usage weirdnesses.
Such symptoms can be caused by limit underruns so double the
sched_runtime_limit.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Was playing with sched_smt_power_savings/sched_mc_power_savings and
found out that while the scheduler domains are reconstructed when sysfs
settings change, rebalance_domains() can get triggered with null domain
on other cpus, which is setting next_balance to jiffies + 60*HZ.
Resulting in no idle/busy balancing for 60 seconds.
Fix this.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On a four package system with HT - HT load balancing optimizations were
broken. For example, if two tasks end up running on two logical threads
of one of the packages, scheduler is not able to pull one of the tasks
to a completely idle package.
In this scenario, for nice-0 tasks, imbalance calculated by scheduler
will be 512 and find_busiest_queue() will return 0 (as each cpu's load
is 1024 > imbalance and has only one task running).
Similarly MC scheduler optimizations also get fixed with this patch.
[ mingo@elte.hu: restored fair balancing by increasing the fuzz and
adding it back to the power decision, without the /2
factor. ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There are two remaining gotchas:
- The directories have impossible permissions (writeable).
- The ctl_name for the kernel directory is inconsistent with
everything else. It should be CTL_KERN.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
construct a more or less wall-clock time out of sched_clock(), by
using ACPI-idle's existing knowledge about how much time we spent
idling. This allows the rq clock to work around TSC-stops-in-C2,
TSC-gets-corrupted-in-C3 type of problems.
( Besides the scheduler's statistics this also benefits blktrace and
printk-timestamps as well. )
Furthermore, the precise before-C2/C3-sleep and after-C2/C3-wakeup
callbacks allow the scheduler to get out the most of the period where
the CPU has a reliable TSC. This results in slightly more precise
task statistics.
the ACPI bits were acked by Len.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Len Brown <len.brown@intel.com>
dequeue_signal:
if (__SI_TIMER) {
spin_unlock(&tsk->sighand->siglock);
do_schedule_next_timer(info);
spin_lock(&tsk->sighand->siglock);
}
Unless tsk == curent, this is absolutely unsafe: nothing prevents tsk from
exiting. If signalfd was passed to another process, do_schedule_next_timer()
is just wrong.
Add yet another "tsk == current" check into dequeue_signal().
This patch fixes an oopsable bug, but breaks the scheduling of posix timers
if the shared __SI_TIMER signal was fetched via signalfd attached to another
sub-thread. Mostly fixed by the next patch.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Roland McGrath <roland@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sys_timer_create() sets ->it_process and unlocks ->siglock, then checks
tmr->it_sigev_notify to define if get_task_struct() is needed.
We already passed ->it_id to the caller, another thread can delete this timer
and free its memory in between.
As a minimal fix, move this code under ->siglock, sys_timer_delete() takes it
too before calling release_posix_timer(). A proper serialization would be to
take ->it_lock, we add a partly initialized timer on posix_timers_id, not
good.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
timer_delete does:
lock_timer();
timer->it_process = NULL;
unlock_timer();
release_posix_timer();
timer->it_process is checked in lock_timer() to prevent access to a
timer, which is on the way to be deleted, but the check happens after
idr_lock is dropped. This allows release_posix_timer() to delete the
timer before the lock code can check the timer:
CPU 0 CPU 1
lock_timer();
timer->it_process = NULL;
unlock_timer();
lock_timer()
spin_lock(idr_lock);
timer = idr_find();
spin_lock(timer->lock);
spin_unlock(idr_lock);
release_posix_timer();
spin_lock(idr_lock);
idr_remove(timer);
spin_unlock(idr_lock);
free_timer(timer);
if (timer->......)
Change the locking to prevent this.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If we're going to run the handler from free_irq() then we must do it with
local irq's disabled. Otherwise lockdep complains that the handler is taking
irq-safe spinlocks in a non-irq-safe fashion.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Avoid futex_unlock_pi returning -EFAULT (which results in deadlock), by
clearing uval before jumping to retry_locked.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes an off-by-one in a BUG_ON() spotted by the Coverity
checker.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Amy Griffis <amy.griffis@hp.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Gerd Hoffmann pointed out that my patch from yesterday can lead
to a null pointer dereference if the kernel is booted with no
console, and no earlyprintk defined. This fixes that issue.
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a followup to the cleanups for earlyprintk patch from Gerd Hoffmann
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=69331af79cf29e26d1231152a172a1a10c2df511
This ensures that a bootconsole is unregistered if it is not replaced.
The current implementation spews garbage out the bootconsole in this case,
since the bootconsole structure is normally in the init section, and is
freed, but still used.
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the second inclusion of linux/capability.h, which has been
introduced with "[PATCH] move capable() to capability.h" (commit
c59ede7b78)
Signed-off-by: Christian Heim <phreak@gentoo.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Level type interrupts are resent by the interrupt hardware when they are
still active at irq_enable().
Suppress the resend mechanism for interrupts marked as level.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 5a43a066b1: "genirq: Allow fasteoi
handler to retrigger disabled interrupts" was erroneously applied to
handle_level_irq(). This added the irq retrigger / resend functionality
to the level irq handler.
Revert the offending bits.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
rebalance_domains(SCHED_IDLE) looks strange (typo), change it to CPU_IDLE.
the effect of this bug was slightly more agressive idle-balancing on
SMP than intended.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Ziljstra noticed that the sleeper bonus deduction code
was not properly rate-limited: a task that scheduled more
frequently would get a disproportionately large deduction.
So limit the deduction to delta_exec.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch makes the following needlessly global code static:
- arch_reinit_sched_domains()
- struct attr_sched_mc_power_savings
- struct attr_sched_smt_power_savings
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
gcc-4.2 is a lot more picky about its symbol handling. EXPORT_SYMBOL no
longer works on symbols that are undefined or defined with static scope.
For example, with CONFIG_PROFILE off, I see:
kernel/profile.c:206: error: __ksymtab_profile_event_unregister causes a section type conflict
kernel/profile.c:205: error: __ksymtab_profile_event_register causes a section type conflict
This patch moves the EXPORTs inside the #ifdef CONFIG_PROFILE, so we
only try to export symbols that are defined.
Also, in kernel/kprobes.c there's an EXPORT_SYMBOL_GPL() for
jprobes_return, which if CONFIG_JPROBES is undefined is a static
inline and gives the same error.
And in drivers/acpi/resources/rsxface.c, there's an
ACPI_EXPORT_SYMBOPL() for a static symbol. If it's static, it's not
accessible from outside the compilation unit, so should bot be exported.
These three changes allow building a zx1_defconfig kernel with gcc 4.2
on IA64.
[akpm@linux-foundation.org: export jpobe_return properly]
Signed-off-by: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I find a function(clockevents_unregister_notifier) which is not called by
anything in tree.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On some systems some PFNs reported by the early initialization code as
'nosave' may be invalid. If we try to set the corresponding bits in the
hibernation bitmap, BUG_ON() in memory_bm_find_bit() will be triggered and
the system won't be able to boot (cf.
https://bugzilla.novell.com/show_bug.cgi?id=296242).
Prevent this from happening by verifying if the 'nosave' PFNs are valid in
mark_nosave_pages().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Misplaced #endif is hiding the numa_zonelist_order sysctl when !SECURITY.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Arjan van de Ven pointed out that we should not print kernel addresses
in world-readable /proc files - fix that.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
improve the rq-clock overflow logic: limit the absolute rq->clock
delta since the last scheduler tick, instead of limiting the delta
itself.
tested by Arjan van de Ven - whole laptop was misbehaving due to
an incorrectly calibrated cpu_khz confusing sched_clock().
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched: (61 commits)
sched: refine negative nice level granularity
sched: fix update_stats_enqueue() reniced codepath
sched: round a bit better
sched: make the multiplication table more accurate
sched: optimize update_rq_clock() calls in the load-balancer
sched: optimize activate_task()
sched: clean up set_curr_task_fair()
sched: remove __update_rq_clock() call from entity_tick()
sched: move the __update_rq_clock() call to scheduler_tick()
sched debug: remove the 'u64 now' parameter from print_task()/_rq()
sched: remove the 'u64 now' local variables
sched: remove the 'u64 now' parameter from deactivate_task()
sched: remove the 'u64 now' parameter from dequeue_task()
sched: remove the 'u64 now' parameter from enqueue_task()
sched: remove the 'u64 now' parameter from dec_nr_running()
sched: remove the 'u64 now' parameter from inc_nr_running()
sched: remove the 'u64 now' parameter from dec_load()
sched: remove the 'u64 now' parameter from inc_load()
sched: remove the 'u64 now' parameter from update_curr_load()
sched: remove the 'u64 now' parameter from ->task_new()
...
This reverts commit 0fc4969b86. It was
always meant to be temporary, but it's generating more useless noise
than anything else, and we probably should never have done it in the
generic kernel (only had the people involved test it on their own).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
refine the granularity of negative nice level tasks: let them
reschedule more often to offset the effect of them consuming
their wait_runtime proportionately slower. (This makes nice-0
task scheduling smoother in the presence of negatively
reniced tasks.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
the key has to be rescaled to /weight even if it has a positive value.
(this change only affects the scheduling of reniced tasks)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
round a tiny bit better in high-frequency rescheduling scenarios,
by rounding around zero instead of rounding down.
(this is pretty theoretical though)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
optimize update_rq_clock() calls in the load-balancer: update them
right after locking the runqueue(s) so that the pull functions do
not have to call it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
optimize activate_task() by removing update_rq_clock() from it.
(and add update_rq_clock() to all callsites of activate_task() that
did not have it before.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
clean up set_curr_task_fair().
( identity transformation that causes no change in functionality. )
text data bss dec hex filename
39170 3750 36 42956 a7cc sched.o.before
39170 3750 36 42956 a7cc sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove __update_rq_clock() call from entity_tick().
no change in functionality because scheduler_tick() already calls
__update_rq_clock().
Signed-off-by: Ingo Molnar <mingo@elte.hu>
move the __update_rq_clock() call from update_cpu_load() to
scheduler_tick().
( identity transformation that causes no change in functionality. )
this allows the direct use of rq->clock in ->task_tick() functions.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the 'u64 now' parameter from sched_debug.c:print_task()/_rq().
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
final step: remove all (now superfluous) 'u64 now' variables.
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the 'u64 now' parameter from deactivate_task().
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the 'u64 now' parameter from dequeue_task().
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the 'u64 now' parameter from enqueue_task().
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the 'u64 now' parameter from dec_nr_running().
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the 'u64 now' parameter from inc_nr_running().
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the 'u64 now' parameter from dec_load().
( identity transformation that causes no change in functionality. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
