Commit graph

143208 commits

Author SHA1 Message Date
Lai Jiangshan
93cfb3c9fd tracing: fix splice return too large
I got these from strace:

 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288
 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288
 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288
 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 16384
 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192
 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192
 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192

I wanted to splice_read 4096 bytes, but it returns 8192 or larger.

It is because the return value of tracing_buffers_splice_read()
does not include "zero out any left over data" bytes.

But tracing_buffers_read() includes these bytes, we make them
consistent.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D46674.9030804@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-10 12:44:46 +02:00
Lai Jiangshan
c7625a555f tracing: update file->f_pos when splice(2) it
Impact: Cleanup

These two lines:

	if (unlikely(*ppos))
		return -ESPIPE;

in tracing_buffers_splice_read() are not needed, VFS layer
has disabled seek(2).

We remove these two lines, and then we can update file->f_pos.

And tracing_buffers_read() updates file->f_pos, this fix
make tracing_buffers_splice_read() updates file->f_pos too.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D46670.4010503@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-10 12:44:44 +02:00
Lai Jiangshan
ddd538f3e6 tracing: allocate page when needed
Impact: Cleanup

Sometimes, we open trace_pipe_raw, but we don't read(2) it,
we just splice(2) it, thus, the page is not used.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D4666B.4010608@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-10 12:44:43 +02:00
Lai Jiangshan
d1e7e02f30 tracing: disable seeking for trace_pipe_raw
Impact: disable pread()

We set tracing_buffers_fops.llseek to no_llseek,
but we can still perform pread() to read this file.

That is not expected.

This fix uses nonseekable_open() to disable it.

tracing_buffers_fops.llseek is still set to no_llseek,
it mark this file is a "non-seekable device" and is used by
sys_splice(). See also do_splice() or manual of splice(2):

ERRORS
       EINVAL Target file system doesn't support  splicing;
              neither  of the descriptors refers to a pipe;
              or offset given for non-seekable device.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D46668.8030806@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-10 12:44:42 +02:00
David Howells
e69cc92788 FRV: Move to arch/frv/include/asm/
Move arch headers from include/asm-frv/ to arch/frv/include/asm/.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-04-10 01:48:06 +01:00
David Howells
187934655f FRV: Fix indentation errors to keep git-am happy when moving arch header files
Fix indentation errors to keep git-am happy when moving arch header files.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-04-10 01:48:01 +01:00
Linus Torvalds
6594d0b1cd Merge git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6: (27 commits)
  xsysace: Fix dereferencing of cf_id after hd_driveid removal
  at91_ide: turn on PIO 6 support
  at91_ide: remove unused ide_mm_{outb,inb}
  ide-cd: reverse NOT_READY sense key logic
  ide: refactor tf_read() method
  ide: refactor tf_load() method
  ide: call write_devctl() method from tf_read() method
  ide: move common code out of tf_load() method
  ide: simplify 'struct ide_taskfile'
  ide: replace IDE_TFLAG_* flags by IDE_VALID_*
  ide-cd: fix intendation in cdrom_decode_status()
  ide-cd: unify handling of fs and pc requests in cdrom_decode_status()
  ide-cd: convert cdrom_decode_status() to use switch statements
  ide-cd: update debugging support
  ide-cd: respect REQ_QUIET for fs requests in cdrom_decode_status()
  ide: remove unused #include <linux/version.h>
  tx4939ide: Fix tx4939ide_{in,out}put_data_swap argument
  tx493[89]ide: Remove big endian version of tx493[89]ide_tf_{load,read}
  ide-cd: carve out an ide_cd_breathe()-helper for fs write requests
  ide-cd: move status checking into the IRQ handler
  ...
2009-04-09 16:43:30 -07:00
Linus Torvalds
0534c8cb5c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  RDMA/nes: Add support for new SFP+ PHY
  RDMA/nes: Add wide_ppm_offset parm for switch compatibility
  RDMA/nes: Fix SFP+ PHY initialization
  RDMA/nes: Fix nes_nic_cm_xmit() error handling
  RDMA/nes: Fix error handling issues
  RDMA/nes: Fix incorrect casts on 32-bit architectures
  IPoIB: Document newish features
  RDMA/cma: Create cm id even when IB port is down
  RDMA/cma: Use rate from IPoIB broadcast when joining IPoIB multicast groups
  IPoIB: Avoid free_netdev() BUG when destroying a child interface
  mlx4_core: Don't leak mailbox for SET_PORT on Ethernet ports
  RDMA/cxgb3: Release dependent resources only when endpoint memory is freed.
  RDMA/cxgb3: Handle EEH events
  IB/mlx4: Use pgprot_writecombine() for BlueFlame pages
2009-04-09 16:42:26 -07:00
Linus Torvalds
54f93b74cf Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: check block device size on mount
  ext4: Fix off-by-one-error in ext4_valid_extent_idx()
  ext4: Fix big-endian problem in __ext4_check_blockref()
2009-04-09 16:42:05 -07:00
Masami Hiramatsu
3b3809ac53 x86: fix set_fixmap to use phys_addr_t
Use phys_addr_t for receiving a physical address argument instead of
unsigned long.  This allows fixmap to handle pages higher than 4GB on
x86-32.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 16:41:45 -07:00
David Howells
62b8e680e6 MN10300: Kill MN10300's own profiling Kconfig
Kill MN10300's own profiling Kconfig as this is superfluous given that the
profiling options have moved to init/Kconfig and arch/Kconfig.  Not only is
this now superfluous, but the dependencies are not correct.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 10:53:16 -07:00
David Howells
6fde836b54 FRV: Use <asm-generic/pgtable.h> in NOMMU mode
asm-frv/pgtable.h could just #include <asm-generic/pgtable.h> in NOMMU mode
rather than #defining macros for lazy MMU and CPU stuff.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 10:46:05 -07:00
David Howells
34574dd10b keys: Handle there being no fallback destination keyring for request_key()
When request_key() is called, without there being any standard process
keyrings on which to fall back if a destination keyring is not specified, an
oops is liable to occur when construct_alloc_key() calls down_write() on
dest_keyring's semaphore.

Due to function inlining this may be seen as an oops in down_write() as called
from request_key_and_link().

This situation crops up during boot, where request_key() is called from within
the kernel (such as in CIFS mounts) where nobody is actually logged in, and so
PAM has not had a chance to create a session keyring and user keyrings to act
as the fallback.

To fix this, make construct_alloc_key() not attempt to cache a key if there is
no fallback key if no destination keyring is given specifically.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 10:41:19 -07:00
Stoyan Gaydarov
11ff5f6aff afs: BUG to BUG_ON changes
Signed-off-by: Stoyan Gaydarov <stoyboyker@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 10:41:19 -07:00
Linus Torvalds
e66dd19092 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: cpu_debug remove execute permission
  x86: smarten /proc/interrupts output for new counters
  x86: DMI match for the Dell DXP061 as it needs BIOS reboot
  x86: make 64 bit to use default_inquire_remote_apic
  x86, setup: un-resequence mode setting for VGA 80x34 and 80x60 modes
  x86, intel-iommu: fix X2APIC && !ACPI build failure
2009-04-09 10:38:23 -07:00
Linus Torvalds
c2ea122cd7 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: consolidate documents
  blktrace: pass the right pointer to kfree()
  tracing/syscalls: use a dedicated file header
  tracing: append a comma to INIT_FTRACE_GRAPH
2009-04-09 10:37:46 -07:00
Linus Torvalds
17b2e9bf27 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: do not count frozen tasks toward load
  sched: refresh MAINTAINERS entry
  sched: Print sched_group::__cpu_power in sched_domain_debug
  cpuacct: add per-cgroup utime/stime statistics
  posixtimers, sched: Fix posix clock monotonicity
  sched_rt: don't allocate cpumask in fastpath
  cpuacct: make cpuacct hierarchy walk in cpuacct_charge() safe when rcupreempt is used -v2
2009-04-09 10:37:28 -07:00
Linus Torvalds
422a253483 Merge branches 'core-fixes-for-linus', 'irq-fixes-for-linus' and 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  printk: fix wrong format string iter for printk
  futex: comment requeue key reference semantics

* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  irq: fix cpumask memory leak on offstack cpumask kernels

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  posix-timers: fix RLIMIT_CPU && setitimer(CPUCLOCK_PROF)
  posix-timers: fix RLIMIT_CPU && fork()
  timers: add missing kernel-doc
2009-04-09 10:35:30 -07:00
Thomas Gleixner
91e58b6e95 MN10300: Convert obsolete no_irq_type to no_irq_chip
Convert the last remaining users to no_irq_chip.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 10:33:21 -07:00
Heiko Carstens
36cd3c9f92 mutex: have non-spinning mutexes on s390 by default
Impact: performance regression fix for s390

The adaptive spinning mutexes will not always do what one would expect on
virtualized architectures like s390. Especially the cpu_relax() loop in
mutex_spin_on_owner might hurt if the mutex holding cpu has been scheduled
away by the hypervisor.

We would end up in a cpu_relax() loop when there is no chance that the
state of the mutex changes until the target cpu has been scheduled again by
the hypervisor.

For that reason we should change the default behaviour to no-spin on s390.

We do have an instruction which allows to yield the current cpu in favour of
a different target cpu. Also we have an instruction which allows us to figure
out if the target cpu is physically backed.

However we need to do some performance tests until we can come up with
a solution that will do the right thing on s390.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
LKML-Reference: <20090409184834.7a0df7b2@osiris.boeblingen.de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-09 19:28:24 +02:00
Linus Torvalds
df5529297e Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm kcopyd: fix callback race
  dm kcopyd: prepare for callback race fix
  dm: implement basic barrier support
  dm: remove dm_request loop
  dm: rework queueing and suspension
  dm: simplify dm_request loop
  dm: split DMF_BLOCK_IO flag into two
  dm: rearrange dm_wq_work
  dm: remove limited barrier support
  dm: add integrity support
2009-04-09 08:01:21 -07:00
Herbert Xu
97c18e2c7a module: try_then_request_module must wait
Since the whole point of try_then_request_module is to retry
the operation after a module has been loaded, we must wait for
the module to fully load.

Otherwise all sort of things start breaking, e.g., you won't
be able to read your encrypted disks on the first attempt.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Tested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 07:49:44 -07:00
Wim Van Sebroeck
3230e8cd80 Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6 2009-04-09 05:51:57 +00:00
Nathan Lynch
e3c8ca8336 sched: do not count frozen tasks toward load
Freezing tasks via the cgroup freezer causes the load average to climb
because the freezer's current implementation puts frozen tasks in
uninterruptible sleep (D state).

Some applications which perform job-scheduling functions consult the
load average when making decisions.  If a cgroup is frozen, the load
average does not provide a useful measure of the system's utilization
to such applications.  This is especially inconvenient if the job
scheduler employs the cgroup freezer as a mechanism for preempting low
priority jobs.  Contrast this with using SIGSTOP for the same purpose:
the stopped tasks do not count toward system load.

Change task_contributes_to_load() to return false if the task is
frozen.  This results in /proc/loadavg behavior that better meets
users' expectations.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Tested-by: Nigel Cunningham <nigel@tuxonice.net>
Cc: <stable@kernel.org>
Cc: containers@lists.linux-foundation.org
Cc: linux-pm@lists.linux-foundation.org
Cc: Matt Helsley <matthltc@us.ibm.com>
LKML-Reference: <20090408194512.47a99b95@manatee.lan>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-09 07:37:02 +02:00
Li Zefan
66bb74888e tracing: consolidate documents
Move kmemtrace.txt, tracepoints.txt, ftrace.txt and mmiotrace.txt to
the new trace/ directory.

I didnt find any references to those documents in both source
files and documents, so no extra work needs to be done.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Pekka Paalanen <pq@iki.fi>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
LKML-Reference: <49DD6E2B.6090200@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-09 07:28:10 +02:00
Jaswinder Singh Rajput
f20ab9c38f x86: cpu_debug remove execute permission
It seems by mistake these files got execute permissions so removing it.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
LKML-Reference: <1239211186.9037.2.camel@ht.satnam>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-09 06:34:02 +02:00
Li Zefan
9eb85125ce blktrace: pass the right pointer to kfree()
Impact: fix kfree crash with non-standard act_mask string

If passing a string with leading white spaces to strstrip(),
the returned ptr != the original ptr.

This bug was introduced by me.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49DD694C.8020902@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-09 05:52:40 +02:00
Frederic Weisbecker
47788c58e6 tracing/syscalls: use a dedicated file header
Impact: fix build warnings and possibe compat misbehavior on IA64

Building a kernel on ia64 might trigger these ugly build warnings:

CC      arch/ia64/ia32/sys_ia32.o
In file included from arch/ia64/ia32/sys_ia32.c:55:
arch/ia64/ia32/ia32priv.h:290:1: warning: "elf_check_arch" redefined
In file included from include/linux/elf.h:7,
                 from include/linux/module.h:14,
                 from include/linux/ftrace.h:8,
                 from include/linux/syscalls.h:68,
                 from arch/ia64/ia32/sys_ia32.c:18:
arch/ia64/include/asm/elf.h:19:1: warning: this is the location of the previous definition
[...]

sys_ia32.c includes linux/syscalls.h which in turn includes linux/ftrace.h
to import the syscalls tracing prototypes.

But including ftrace.h can pull too much things for a low level file,
especially on ia64 where the ia32 private headers conflict with higher
level headers.

Now we isolate the syscall tracing headers in their own lightweight file.

Reported-by: Tony Luck <tony.luck@intel.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jason Baron <jbaron@redhat.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Michael Davidson <md@google.com>
LKML-Reference: <20090408184058.GB6017@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-09 05:43:32 +02:00
Linus Torvalds
f4efdd65b7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  work_on_cpu(): rewrite it to create a kernel thread on demand
  kthread: move sched-realeted initialization from kthreadd context
  kthread: Don't looking for a task in create_kthread() #2
2009-04-08 18:00:55 -07:00
Linus Torvalds
d831220476 Merge git://git.infradead.org/battery-2.6
* git://git.infradead.org/battery-2.6:
  pda_power: Add optional OTG transceiver and voltage regulator support
  pcf50633_charger: Remove unused mbc_set_status function
  pcf50633_charger: Enable periodic charging restart
2009-04-08 17:45:02 -07:00
Linus Torvalds
3d4d4c8bb6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  cap_prctl: don't set error to 0 at 'no_change'
2009-04-08 17:44:28 -07:00
Linus Torvalds
c71d9caf6c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  igb: remove sysfs entry that was used to set the number of vfs
  igbvf: add new driver to support 82576 virtual functions
  drivers/net/eql.c: Fix a dev leakage.
  niu: Fix unused variable warning.
  r6040: set MODULE_VERSION
  bnx2: Don't use reserved names
  FEC driver: add missing #endif
  niu: Fix error handling
  mv643xx_eth: don't reset the rx coal timer on interface up
  smsc911x: correct debugging message on mii read timeout
  ethoc: fix library build errors
  netfilter: ctnetlink: fix regression in expectation handling
  netfilter: fix selection of "LED" target in netfilter
  netfilter: ip6tables regression fix
2009-04-08 17:43:58 -07:00
Linus Torvalds
a219ee88b6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc: Hook up sys_preadv and sys_pwritev
  sparc64: add_node_ranges() must be __init
  serial: sunsu: sunsu_kbd_ms_init needs to be __devinit
  sparc: Fix section mismatch warnings in cs4231 sound driver.
  sparc64: Fix section mismatch warnings in PCI controller drivers.
  sparc64: Fix section mismatch warnings in power driver.
  sparc64: get_cells() can't be marked __init
2009-04-08 17:43:39 -07:00
Linus Torvalds
a7b334de4d Merge branch 'ext3-latency-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'ext3-latency-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext3: Try to avoid starting a transaction in writepage for data=writepage
  block_write_full_page: switch synchronous writes to use WRITE_SYNC_PLUG
2009-04-08 17:42:32 -07:00
Andrew Morton
6b44003e5c work_on_cpu(): rewrite it to create a kernel thread on demand
Impact: circular locking bugfix

The various implemetnations and proposed implemetnations of work_on_cpu()
are vulnerable to various deadlocks because they all used queues of some
form.

Unrelated pieces of kernel code thus gained dependencies wherein if one
work_on_cpu() caller holds a lock which some other work_on_cpu() callback
also takes, the kernel could rarely deadlock.

Fix this by creating a short-lived kernel thread for each work_on_cpu()
invokation.

This is not terribly fast, but the only current caller of work_on_cpu() is
pci_call_probe().

It would be nice to find some other way of doing the node-local
allocations in the PCI probe code so that we can zap work_on_cpu()
altogether.  The code there is rather nasty.  I can't think of anything
simple at this time...

Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-04-09 09:50:37 +09:30
Oleg Nesterov
1c99315bb3 kthread: move sched-realeted initialization from kthreadd context
kthreadd is the single thread which implements ths "create" request, move
sched_setscheduler/etc from create_kthread() to kthread_create() to
improve the scalability.

We should be careful with sched_setscheduler(), use _nochek helper.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Vitaliy Gusev <vgusev@openvz.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-04-09 09:50:37 +09:30
Vitaliy Gusev
3217ab97f1 kthread: Don't looking for a task in create_kthread() #2
Remove the unnecessary find_task_by_pid_ns(). kthread() can just
use "current" to get the same result.

Signed-off-by: Vitaliy Gusev <vgusev@openvz.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-04-09 09:50:36 +09:30
Mikulas Patocka
340cd44451 dm kcopyd: fix callback race
If the thread calling dm_kcopyd_copy is delayed due to scheduling inside
split_job/segment_complete and the subjobs complete before the loop in
split_job completes, the kcopyd callback could be invoked from the
thread that called dm_kcopyd_copy instead of the kcopyd workqueue.

dm_kcopyd_copy -> split_job -> segment_complete -> job->fn()

Snapshots depend on the fact that callbacks are called from the singlethreaded
kcopyd workqueue and expect that there is no racing between individual
callbacks. The racing between callbacks can lead to corruption of exception
store and it can also mean that exception store callbacks are called twice
for the same exception - a likely reason for crashes reported inside
pending_complete() / remove_exception().

This patch fixes two problems:

1. job->fn being called from the thread that submitted the job (see above).

- Fix: hand over the completion callback to the kcopyd thread.

2. job->fn(read_err, write_err, job->context); in segment_complete
reports the error of the last subjob, not the union of all errors.

- Fix: pass job->write_err to the callback to report all error bits
  (it is done already in run_complete_job)

Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:17 +01:00
Mikulas Patocka
73830857bc dm kcopyd: prepare for callback race fix
Use a variable in segment_complete() to point to the dm_kcopyd_client
struct and only release job->pages in run_complete_job() if any are
defined.  These changes are needed by the next patch.

Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:16 +01:00
Mikulas Patocka
af7e466a1a dm: implement basic barrier support
Barriers are submitted to a worker thread that issues them in-order.

The thread is modified so that when it sees a barrier request it waits
for all pending IO before the request then submits the barrier and
waits for it.  (We must wait, otherwise it could be intermixed with
following requests.)

Errors from the barrier request are recorded in a per-device barrier_error
variable. There may be only one barrier request in progress at once.

For now, the barrier request is converted to a non-barrier request when
sending it to the underlying device.

This patch guarantees correct barrier behavior if the underlying device
doesn't perform write-back caching. The same requirement existed before
barriers were supported in dm.

Bottom layer barrier support (sending barriers by target drivers) and
handling devices with write-back caches will be done in further patches.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:16 +01:00
Mikulas Patocka
92c639021c dm: remove dm_request loop
Remove queue_io return value and a loop in dm_request.

IO may be submitted to a worker thread with queue_io().  queue_io() sets
DMF_QUEUE_IO_TO_THREAD so that all further IO is queued for the thread. When
the thread finishes its work, it clears DMF_QUEUE_IO_TO_THREAD and from this
point on, requests are submitted from dm_request again. This will be used
for processing barriers.

Remove the loop in dm_request. queue_io() can submit I/Os to the worker thread
even if DMF_QUEUE_IO_TO_THREAD was not set.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:15 +01:00
Mikulas Patocka
3b00b2036f dm: rework queueing and suspension
Rework shutting down on suspend and document the associated rules.

Drop write lock in __split_and_process_bio to allow more processing
concurrency.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:15 +01:00
Alasdair G Kergon
54d9a1b451 dm: simplify dm_request loop
Refactor the code in dm_request().

Require the new DMF_BLOCK_FOR_SUSPEND flag on readahead bios we will
discard so we don't drop such bios while processing a barrier.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:14 +01:00
Alasdair G Kergon
1eb787ec18 dm: split DMF_BLOCK_IO flag into two
Split the DMF_BLOCK_IO flag into two.

DMF_BLOCK_IO_FOR_SUSPEND is set when I/O must be blocked while suspending a
device.  DMF_QUEUE_IO_TO_THREAD is set when I/O must be queued to a
worker thread for later processing.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:14 +01:00
Alasdair G Kergon
df12ee9963 dm: rearrange dm_wq_work
Refactor dm_wq_work() to make later patch more readable.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:13 +01:00
Mikulas Patocka
692d0eb9e0 dm: remove limited barrier support
Prepare for full barrier implementation: first remove the restricted support.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:13 +01:00
Martin K. Petersen
9c47008d13 dm: add integrity support
This patch provides support for data integrity passthrough in the device
mapper.

 - If one or more component devices support integrity an integrity
   profile is preallocated for the DM device.

 - If all component devices have compatible profiles the DM device is
   flagged as capable.

 - Handle integrity metadata when splitting and cloning bios.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-04-09 00:27:12 +01:00
Serge E. Hallyn
5bf37ec3e0 cap_prctl: don't set error to 0 at 'no_change'
One-liner: capsh --print is broken without this patch.

In certain cases, cap_prctl returns error > 0 for success.  However,
the 'no_change' label was always setting error to 0.  As a result,
for example, 'prctl(CAP_BSET_READ, N)' would always return 0.
It should return 1 if a process has N in its bounding set (as
by default it does).

I'm keeping the no_change label even though it's now functionally
the same as 'error'.

Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-04-09 09:12:03 +10:00
Alexander Duyck
2a3abf6d17 igb: remove sysfs entry that was used to set the number of vfs
This patch removes the sysfs entry num_vfs which was added to support
enabling pci virtual functions for 82576.

To prevent VFs from loading automatically a module parameter "max_vfs" was
added so that the number of VFs per PF can be limited.  This is especially
useful when 4 or more 82576 ports are on the system because otherwise to
load all VFs would result in 8 interface per physical port.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-08 16:03:15 -07:00
Alexander Duyck
d4e0fe01a3 igbvf: add new driver to support 82576 virtual functions
This adds an igbvf driver to handle virtual functions provided by the
igb driver when SR-IOV has been enabled.  A virtual function is a
lightweight pci-e function that supports a single queue and shares
resources with the 82576 physical function contained within the igb
driver.

To spawn virtual functions from the igb driver all that is needed is to
enable CONFIG_PCI_IOV and have an 82576 Ethernet adapter on a system that
supports SR-IOV in the BIOS.  The virtual functions will appear after the
interface is loaded.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-08 16:03:14 -07:00