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899 commits

Author SHA1 Message Date
Josh Triplett
f505c553db debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options
Several debugging options currently default to y, such as
CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA.  Embedded users
might want to turn those options off to save space; however,
turning them off requires turning on CONFIG_DEBUG_KERNEL to
unhide them.  Since CONFIG_DEBUG_KERNEL exists specifically to
unhide debugging options, and CONFIG_EXPERT exists specifically
to unhide options potentially needed by experts and/or embedded
users, make CONFIG_EXPERT automatically imply
CONFIG_DEBUG_KERNEL.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20110606012358.GA1909@leaf
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-06-07 00:05:15 +02:00
Linus Torvalds
6345d24daf mm: Fix boot crash in mm_alloc()
Thomas Gleixner reports that we now have a boot crash triggered by
CONFIG_CPUMASK_OFFSTACK=y:

    BUG: unable to handle kernel NULL pointer dereference at   (null)
    IP: [<c11ae035>] find_next_bit+0x55/0xb0
    Call Trace:
     [<c11addda>] cpumask_any_but+0x2a/0x70
     [<c102396b>] flush_tlb_mm+0x2b/0x80
     [<c1022705>] pud_populate+0x35/0x50
     [<c10227ba>] pgd_alloc+0x9a/0xf0
     [<c103a3fc>] mm_init+0xec/0x120
     [<c103a7a3>] mm_alloc+0x53/0xd0

which was introduced by commit de03c72cfc ("mm: convert
mm->cpu_vm_cpumask into cpumask_var_t"), and is due to wrong ordering of
mm_init() vs mm_init_cpumask

Thomas wrote a patch to just fix the ordering of initialization, but I
hate the new double allocation in the fork path, so I ended up instead
doing some more radical surgery to clean it all up.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-29 11:32:28 -07:00
Daniel Lezcano
a77aea9201 cgroup: remove the ns_cgroup
The ns_cgroup is an annoying cgroup at the namespace / cgroup frontier and
leads to some problems:

  * cgroup creation is out-of-control
  * cgroup name can conflict when pids are looping
  * it is not possible to have a single process handling a lot of
    namespaces without falling in a exponential creation time
  * we may want to create a namespace without creating a cgroup

  The ns_cgroup was replaced by a compatibility flag 'clone_children',
  where a newly created cgroup will copy the parent cgroup values.
  The userspace has to manually create a cgroup and add a task to
  the 'tasks' file.

This patch removes the ns_cgroup as suggested in the following thread:

https://lists.linux-foundation.org/pipermail/containers/2009-June/018616.html

The 'cgroup_clone' function is removed because it is no longer used.

This is a userspace-visible change.  Commit 45531757b4 ("cgroup: notify
ns_cgroup deprecated") (merged into 2.6.27) caused the kernel to emit a
printk warning users that the feature is planned for removal.  Since that
time we have heard from XXX users who were affected by this.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jamal Hadi Salim <hadi@cyberus.ca>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:34 -07:00
Mike Travis
162a7e7500 printk: allocate kernel log buffer earlier
On larger systems, because of the numerous ACPI, Bootmem and EFI messages,
the static log buffer overflows before the larger one specified by the
log_buf_len param is allocated.  Minimize the overflow by allocating the
new log buffer as soon as possible.

On kernels without memblock, a later call to setup_log_buf from
kernel/init.c is the fallback.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix CONFIG_PRINTK=n build]
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jack Steiner <steiner@sgi.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>
2011-05-25 08:39:48 -07:00
Andrew Worsley
d2b463135f init/calibrate.c: fix for critical bogoMIPS intermittent calculation failure
A fix to the TSC (Time Stamp Counter) based bogoMIPS calculation used on
secondary CPUs which has two faults:

1: Not handling wrapping of the lower 32 bits of the TSC counter on
   32bit kernel - perhaps TSC is not reset by a warm reset?

2: TSC and Jiffies are no incrementing together properly.  Either
   jiffies increment too quickly or Time Stamp Counter isn't incremented
   in during an SMI but the real time clock is and jiffies are
   incremented.

Case 1 can result in a factor of 16 too large a value which makes udelay()
values too small and can cause mysterious driver errors.  Case 2 appears
to give smaller 10-15% errors after averaging but enough to cause
occasional failures on my own board

I have tested this code on my own branch and attach patch suitable for
current kernel code.  See below for examples of the failures and how the
fix handles these situations now.

I reported this issue earlier here:
     Intermittent problem with BogoMIPs calculation on Intel AP CPUs -
http://marc.info/?l=linux-kernel&m=129947246316875&w=4

I suspect this issue has been seen by others but as it is intermittent and
bogoMIPS for secondary CPUs are no longer printed out it might have been
difficult to identify this as the cause.  Perhaps these unresolved issues,
although quite old, might be relevant as possibly this fault has been
around for a while.  In particular Case 1 may only be relevant to 32bit
kernels on newer HW (most people run 64bit kernels?).  Case 2 is less
dramatic since the earlier fix in this area and also intermittent.

   Re: bogomips discrepancy on Intel Core2 Quad CPU -
http://marc.info/?l=linux-kernel&m=118929277524298&w=4
   slow system and bogus bogomips  -
http://marc.info/?l=linux-kernel&m=116791286716107&w=4
   Re: Re: [RFC-PATCH] clocksource: update lpj if clocksource has -
http://marc.info/?l=linux-kernel&m=128952775819467&w=4

This issue is masked a little by commit feae3203d7 ("timers, init:
Limit the number of per cpu calibration bootup messages") which only
prints out the first bogoMIPS value making it much harder to notice other
values differing.  Perhaps it should be changed to only suppress them when
they are similar values?

Here are some outputs showing faults occurring and the new code handling
them properly.  See my earlier message for examples of the original
failure.

    Case 1:   A Time Stamp Counter wrap:
...
Calibrating delay loop (skipped), value calculated using timer
frequency.. 6332.70 BogoMIPS (lpj=31663540)
....
calibrate_delay_direct() timer_rate_max=31666493
timer_rate_min=31666151 pre_start=4170369255 pre_end=4202035539
calibrate_delay_direct() timer_rate_max=2425955274
timer_rate_min=2425954941 pre_start=4265368533 pre_end=2396356387
calibrate_delay_direct() ignoring timer_rate as we had a TSC wrap
around start=4265368581 >=post_end=2396356511
calibrate_delay_direct() timer_rate_max=31666274
timer_rate_min=31665942 pre_start=2440373374 pre_end=2472039515
calibrate_delay_direct() timer_rate_max=31666492
timer_rate_min=31666160 pre_start=2535372139 pre_end=2567038422
calibrate_delay_direct() timer_rate_max=31666455
timer_rate_min=31666207 pre_start=2630371084 pre_end=2662037415
Calibrating delay using timer specific routine.. 6333.28 BogoMIPS (lpj=31666428)
Total of 2 processors activated (12665.99 BogoMIPS).
....

    Case 2:  Some thing (presumably the SMM interrupt?) causing the
very low increase in TSC counter for the DELAY_CALIBRATION_TICKS
increase in jiffies
...
Calibrating delay loop (skipped), value calculated using timer
frequency.. 6333.25 BogoMIPS (lpj=31666270)
...
calibrate_delay_direct() timer_rate_max=31666483
timer_rate_min=31666074 pre_start=4199536526 pre_end=4231202809
calibrate_delay_direct() timer_rate_max=864348 timer_rate_min=864016
pre_start=2405343672 pre_end=2406207897
calibrate_delay_direct() timer_rate_max=31666483
timer_rate_min=31666179 pre_start=2469540464 pre_end=2501206823
calibrate_delay_direct() timer_rate_max=31666511
timer_rate_min=31666122 pre_start=2564539400 pre_end=2596205712
calibrate_delay_direct() timer_rate_max=31666084
timer_rate_min=31665685 pre_start=2659538782 pre_end=2691204657
calibrate_delay_direct() dropping min bogoMips estimate 1 = 864348
Calibrating delay using timer specific routine.. 6333.27 BogoMIPS (lpj=31666390)
Total of 2 processors activated (12666.53 BogoMIPS).
...

After 70 boots I saw 2 variations <1% slip through

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix straggly printk mess]
Signed-off-by: Andrew Worsley <amworsley@gmail.com>
Reviewed-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:46 -07:00
KOSAKI Motohiro
de03c72cfc mm: convert mm->cpu_vm_cpumask into cpumask_var_t
cpumask_t is very big struct and cpu_vm_mask is placed wrong position.
It might lead to reduce cache hit ratio.

This patch has two change.
1) Move the place of cpumask into last of mm_struct. Because usually cpumask
   is accessed only front bits when the system has cpu-hotplug capability
2) Convert cpu_vm_mask into cpumask_var_t. It may help to reduce memory
   footprint if cpumask_size() will use nr_cpumask_bits properly in future.

In addition, this patch change the name of cpu_vm_mask with cpu_vm_mask_var.
It may help to detect out of tree cpu_vm_mask users.

This patch has no functional change.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:21 -07:00
Linus Torvalds
2bb732cdb4 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  kbuild: make KBUILD_NOCMDDEP=1 handle empty built-in.o
  scripts/kallsyms.c: fix potential segfault
  scripts/gen_initramfs_list.sh: Convert to a /bin/sh script
  kbuild: Fix GNU make v3.80 compatibility
  kbuild: Fix passing -Wno-* options to gcc 4.4+
  kbuild: move scripts/basic/docproc.c to scripts/docproc.c
  kbuild: Fix Makefile.asm-generic for um
  kbuild: Allow to combine multiple W= levels
  kbuild: Disable -Wunused-but-set-variable for gcc 4.6.0
  Fix handling of backlash character in LINUX_COMPILE_BY name
  kbuild: asm-generic support
  kbuild: implement several W= levels
  kbuild: Fix build with binutils <= 2.19
  initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries
  kbuild: Allow to override LINUX_COMPILE_BY and LINUX_COMPILE_HOST macros
  kbuild: Drop unused LINUX_COMPILE_TIME and LINUX_COMPILE_DOMAIN macros
  kbuild: Use the deterministic mode of ar
  kbuild: Call gzip with -n
  kbuild: move KALLSYMS_EXTRA_PASS from Kconfig to Makefile
  Kconfig: improve KALLSYMS_ALL documentation

Fix up trivial conflict in Makefile
2011-05-24 13:31:37 -07:00
Linus Torvalds
e98bae7592 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next-2.6: (28 commits)
  sparc32: fix build, fix missing cpu_relax declaration
  SCHED_TTWU_QUEUE is not longer needed since sparc32 now implements IPI
  sparc32,leon: Remove unnecessary page_address calls in LEON DMA API.
  sparc: convert old cpumask API into new one
  sparc32, sun4d: Implemented SMP IPIs support for SUN4D machines
  sparc32, sun4m: Implemented SMP IPIs support for SUN4M machines
  sparc32,leon: Implemented SMP IPIs for LEON CPU
  sparc32: implement SMP IPIs using the generic functions
  sparc32,leon: SMP power down implementation
  sparc32,leon: added some SMP comments
  sparc: add {read,write}*_be routines
  sparc32,leon: don't rely on bootloader to mask IRQs
  sparc32,leon: operate on boot-cpu IRQ controller registers
  sparc32: always define boot_cpu_id
  sparc32: removed unused code, implemented by generic code
  sparc32: avoid build warning at mm/percpu.c:1647
  sparc32: always register a PROM based early console
  sparc32: probe for cpu info only during startup
  sparc: consolidate show_cpuinfo in cpu.c
  sparc32,leon: implement genirq CPU affinity
  ...
2011-05-22 22:06:24 -07:00
Linus Torvalds
281dc5c5ec Give up on pushing CC_OPTIMIZE_FOR_SIZE
I still happen to believe that I$ miss costs are a major thing, but
sadly, -Os doesn't seem to be the solution.  With or without it, gcc
will miss some obvious code size improvements, and with it enabled gcc
will sometimes make choices that aren't good even with high I$ miss
ratios.

For example, with -Os, gcc on x86 will turn a 20-byte constant memcpy
into a "rep movsl".  While I sincerely hope that x86 CPU's will some day
do a good job at that, they certainly don't do it yet, and the cost is
higher than a L1 I$ miss would be.

Some day I hope we can re-enable this.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-22 14:30:36 -07:00
Daniel Hellstrom
17d9f311ec SCHED_TTWU_QUEUE is not longer needed since sparc32 now implements IPI
Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-20 13:10:55 -07:00
Linus Torvalds
eb04f2f04e Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (78 commits)
  Revert "rcu: Decrease memory-barrier usage based on semi-formal proof"
  net,rcu: convert call_rcu(prl_entry_destroy_rcu) to kfree
  batman,rcu: convert call_rcu(softif_neigh_free_rcu) to kfree_rcu
  batman,rcu: convert call_rcu(neigh_node_free_rcu) to kfree()
  batman,rcu: convert call_rcu(gw_node_free_rcu) to kfree_rcu
  net,rcu: convert call_rcu(kfree_tid_tx) to kfree_rcu()
  net,rcu: convert call_rcu(xt_osf_finger_free_rcu) to kfree_rcu()
  net/mac80211,rcu: convert call_rcu(work_free_rcu) to kfree_rcu()
  net,rcu: convert call_rcu(wq_free_rcu) to kfree_rcu()
  net,rcu: convert call_rcu(phonet_device_rcu_free) to kfree_rcu()
  perf,rcu: convert call_rcu(swevent_hlist_release_rcu) to kfree_rcu()
  perf,rcu: convert call_rcu(free_ctx) to kfree_rcu()
  net,rcu: convert call_rcu(__nf_ct_ext_free_rcu) to kfree_rcu()
  net,rcu: convert call_rcu(net_generic_release) to kfree_rcu()
  net,rcu: convert call_rcu(netlbl_unlhsh_free_addr6) to kfree_rcu()
  net,rcu: convert call_rcu(netlbl_unlhsh_free_addr4) to kfree_rcu()
  security,rcu: convert call_rcu(sel_netif_free) to kfree_rcu()
  net,rcu: convert call_rcu(xps_dev_maps_release) to kfree_rcu()
  net,rcu: convert call_rcu(xps_map_release) to kfree_rcu()
  net,rcu: convert call_rcu(rps_map_release) to kfree_rcu()
  ...
2011-05-19 18:14:34 -07:00
Linus Torvalds
80fe02b5da Merge branches 'sched-core-for-linus' and 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
  sched: Fix and optimise calculation of the weight-inverse
  sched: Avoid going ahead if ->cpus_allowed is not changed
  sched, rt: Update rq clock when unthrottling of an otherwise idle CPU
  sched: Remove unused parameters from sched_fork() and wake_up_new_task()
  sched: Shorten the construction of the span cpu mask of sched domain
  sched: Wrap the 'cfs_rq->nr_spread_over' field with CONFIG_SCHED_DEBUG
  sched: Remove unused 'this_best_prio arg' from balance_tasks()
  sched: Remove noop in alloc_rt_sched_group()
  sched: Get rid of lock_depth
  sched: Remove obsolete comment from scheduler_tick()
  sched: Fix sched_domain iterations vs. RCU
  sched: Next buddy hint on sleep and preempt path
  sched: Make set_*_buddy() work on non-task entities
  sched: Remove need_migrate_task()
  sched: Move the second half of ttwu() to the remote cpu
  sched: Restructure ttwu() some more
  sched: Rename ttwu_post_activation() to ttwu_do_wakeup()
  sched: Remove rq argument from ttwu_stat()
  sched: Remove rq->lock from the first half of ttwu()
  sched: Drop rq->lock from sched_exec()
  ...

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix rt_rq runtime leakage bug
2011-05-19 17:41:22 -07:00
Catalin Marinas
9b090f2da8 kmemleak: Initialise kmemleak after debug_objects_mem_init()
Kmemleak frees objects via RCU and when CONFIG_DEBUG_OBJECTS_RCU_HEAD
is enabled, the RCU callback triggers a call to free_object() in
lib/debugobjects.c. Since kmemleak is initialised before debug objects
initialisation, it may result in a kernel panic during booting. This
patch moves the kmemleak_init() call after debug_objects_mem_init().

Reported-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Tested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@kernel.org>
2011-05-19 17:36:37 +01:00
Ingo Molnar
9cb5baba5e Merge commit 'v2.6.39-rc7' into sched/core 2011-05-12 09:36:18 +02:00
David Rientjes
21a43e397e slub: Revert "[PARISC] slub: fix panic with DISCONTIGMEM"
This reverts commit 4a5fa3590f, which did not allow SLUB to be used
on architectures that use DISCONTIGMEM without compiling NUMA support
without CONFIG_BROKEN also set.

The slub panic that it was intended to prevent is addressed by
d9b41e0b54 ("[PARISC] set memory ranges in N_NORMAL_MEMORY when
onlined") on parisc so there is no further slub issues with such a
configuration.

The reverts allows SLUB now to be used on such architectures since
there haven't been any reports of additional errors.

Cc: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-10 17:37:34 -07:00
Paul E. McKenney
27f4d28057 rcu: priority boosting for TREE_PREEMPT_RCU
Add priority boosting for TREE_PREEMPT_RCU, similar to that for
TINY_PREEMPT_RCU.  This is enabled by the default-off RCU_BOOST
kernel parameter.  The priority to which to boost preempted
RCU readers is controlled by the RCU_BOOST_PRIO kernel parameter
(defaulting to real-time priority 1) and the time to wait before
boosting the readers who are blocking a given grace period is
controlled by the RCU_BOOST_DELAY kernel parameter (defaulting to
500 milliseconds).

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-05-05 23:16:55 -07:00
Linus Torvalds
e8dad69408 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
  [PARISC] slub: fix panic with DISCONTIGMEM
  [PARISC] set memory ranges in N_NORMAL_MEMORY when onlined
2011-04-27 15:20:33 -07:00
Randy Dunlap
6befe5f69b init/Kconfig: fix EXPERT menu list
The EXPERT menu list was recently broken by the insertion of a
kconfig symbol (EMBEDDED) at the beginning of the EXPERT list of
kconfig items.  Broken by:

  commit 6a108a14fa
  Author: David Rientjes <rientjes@google.com>
  Date:   Thu Jan 20 14:44:16 2011 -0800
    kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT

Restore the EXPERT menu list -- don't inject a symbol (EMBEDDED)
that does not depend on EXPERT into the list.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Peter Foley <pefoley2@verizon.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-26 20:48:37 -07:00
James Bottomley
4a5fa3590f [PARISC] slub: fix panic with DISCONTIGMEM
Slub makes assumptions about page_to_nid() which are violated by
DISCONTIGMEM and !NUMA.  This violation results in a panic because
page_to_nid() can be non-zero for pages in the discontiguous ranges and
this leads to a null return by get_node().  The assertion by the
maintainer is that DISCONTIGMEM should only be allowed when NUMA is also
defined.  However, at least six architectures: alpha, ia64, m32r, m68k,
mips, parisc violate this.  The panic is a regression against slab, so
just mark slub broken in the problem configuration to prevent users
reporting these panics.

Cc: stable@kernel.org
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-04-22 15:42:46 -05:00
Artem Bityutskiy
1e2795a119 kbuild: move KALLSYMS_EXTRA_PASS from Kconfig to Makefile
At the moment we have the CONFIG_KALLSYMS_EXTRA_PASS Kconfig switch,
which users can enable or disable while configuring the kernel. This
option is then used by 'make' to determine whether an extra kallsyms
pass is needed or not.

However, this approach is not nice and confusing, and this patch moves
CONFIG_KALLSYMS_EXTRA_PASS from Kconfig to Makefile instead. The
rationale is below.

1. CONFIG_KALLSYMS_EXTRA_PASS is really about the build time, not
   run-time. There is no real need for it to be in Kconfig. It is
   just an additional work-around which should be used only in rare
   cases, when someone breaks kallsyms, so Kbuild/Makefile is much
   better place for this option.
2. Grepping CONFIG_KALLSYMS_EXTRA_PASS shows that many defconfigs have
   it enabled, probably not because they try to work-around a kallsyms
   bug, but just because the Kconfig help text is confusing and does
   not really make it clear that this option should not be used unless
   except when kallsyms is broken.
3. And since many people have CONFIG_KALLSYMS_EXTRA_PASS enabled in
   their Kconfig, we do might fail to notice kallsyms bugs in time. E.g.,
   many testers use "make allyesconfig" to test builds, which will enable
   CONFIG_KALLSYMS_EXTRA_PASS and kallsyms breakage will not be noticed.

To address that, this patch:

1. Kills CONFIG_KALLSYMS_EXTRA_PASS
2. Changes Makefile so that people can use "make KALLSYMS_EXTRA_PASS=1"
   to enable the extra pass if needed. Additionally, they may define
   KALLSYMS_EXTRA_PASS as an environment variable.
3. By default KALLSYMS_EXTRA_PASS is disabled and if kallsyms has issues,
   "make" should print a warning and suggest using KALLSYMS_EXTRA_PASS

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
[mmarek: Removed make help text, is not necessary]
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-15 15:56:15 +02:00
Artem Bityutskiy
71a83ec7da Kconfig: improve KALLSYMS_ALL documentation
Dumb users like myself are not able to grasp from the existing KALLSYMS_ALL
documentation that this option is not what they need. Improve the help
message and make it clearer that KALLSYMS is enough in the majority of
use cases, and KALLSYMS_ALL should really be used very rarely.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-15 15:48:01 +02:00
Peter Zijlstra
317f394160 sched: Move the second half of ttwu() to the remote cpu
Now that we've removed the rq->lock requirement from the first part of
ttwu() and can compute placement without holding any rq->lock, ensure
we execute the second half of ttwu() on the actual cpu we want the
task to run on.

This avoids having to take rq->lock and doing the task enqueue
remotely, saving lots on cacheline transfers.

As measured using: http://oss.oracle.com/~mason/sembench.c

  $ for i in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor ; do echo performance > $i; done
  $ echo 4096 32000 64 128 > /proc/sys/kernel/sem
  $ ./sembench -t 2048 -w 1900 -o 0

  unpatched: run time 30 seconds 647278 worker burns per second
  patched:   run time 30 seconds 816715 worker burns per second

Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152729.515897185@chello.nl
2011-04-14 08:52:41 +02:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Serge E. Hallyn
59607db367 userns: add a user_namespace as creator/owner of uts_namespace
The expected course of development for user namespaces targeted
capabilities is laid out at https://wiki.ubuntu.com/UserNamespace.

Goals:

- Make it safe for an unprivileged user to unshare namespaces.  They
  will be privileged with respect to the new namespace, but this should
  only include resources which the unprivileged user already owns.

- Provide separate limits and accounting for userids in different
  namespaces.

Status:

  Currently (as of 2.6.38) you can clone with the CLONE_NEWUSER flag to
  get a new user namespace if you have the CAP_SYS_ADMIN, CAP_SETUID, and
  CAP_SETGID capabilities.  What this gets you is a whole new set of
  userids, meaning that user 500 will have a different 'struct user' in
  your namespace than in other namespaces.  So any accounting information
  stored in struct user will be unique to your namespace.

  However, throughout the kernel there are checks which

  - simply check for a capability.  Since root in a child namespace
    has all capabilities, this means that a child namespace is not
    constrained.

  - simply compare uid1 == uid2.  Since these are the integer uids,
    uid 500 in namespace 1 will be said to be equal to uid 500 in
    namespace 2.

  As a result, the lxc implementation at lxc.sf.net does not use user
  namespaces.  This is actually helpful because it leaves us free to
  develop user namespaces in such a way that, for some time, user
  namespaces may be unuseful.

Bugs aside, this patchset is supposed to not at all affect systems which
are not actively using user namespaces, and only restrict what tasks in
child user namespace can do.  They begin to limit privilege to a user
namespace, so that root in a container cannot kill or ptrace tasks in the
parent user namespace, and can only get world access rights to files.
Since all files currently belong to the initila user namespace, that means
that child user namespaces can only get world access rights to *all*
files.  While this temporarily makes user namespaces bad for system
containers, it starts to get useful for some sandboxing.

I've run the 'runltplite.sh' with and without this patchset and found no
difference.

This patch:

copy_process() handles CLONE_NEWUSER before the rest of the namespaces.
So in the case of clone(CLONE_NEWUSER|CLONE_NEWUTS) the new uts namespace
will have the new user namespace as its owner.  That is what we want,
since we want root in that new userns to be able to have privilege over
it.

Changelog:
	Feb 15: don't set uts_ns->user_ns if we didn't create
		a new uts_ns.
	Feb 23: Move extern init_user_ns declaration from
		init/version.c to utsname.h.

Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:59 -07:00
Eric W. Biederman
45a68628d3 pid: remove the child_reaper special case in init/main.c
This patchset is a cleanup and a preparation to unshare the pid namespace.
These prerequisites prepare for Eric's patchset to give a file descriptor
to a namespace and join an existing namespace.

This patch:

It turns out that the existing assignment in copy_process of the
child_reaper can handle the initial assignment of child_reaper we just
need to generalize the test in kernel/fork.c

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:57 -07:00
Davidlohr Bueso
ea611b2699 init: return proper error code in do_mounts_rd()
In do_mounts_rd() if memory cannot be allocated, return -ENOMEM.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:15 -07:00
Phil Carmody
b1b5f65e53 calibrate: retry with wider bounds when converge seems to fail
Systems with unmaskable interrupts such as SMIs may massively
underestimate loops_per_jiffy, and fail to converge anywhere near the real
value.  A case seen on x86_64 was an initial estimate of 256<<12, which
converged to 511<<12 where the real value should have been over 630<<12.
This admitedly requires bypassing the TSC calibration (lpj_fine), and a
failure to settle in the direct calibration too, but is physically
possible.  This failure does not depend on my previous calibration
optimisation, but by luck is easy to fix with the optimisation in place
with a trivial retry loop.

In the context of the optimised converging method, as we can no longer
trust the starting estimate, enlarge the search bounds exponentially so
that the number of retries is logarithmically bounded.

[akpm@linux-foundation.org: mention x86_64 SMIs in comment]
Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Tested-by: Stephen Boyd <sboyd@codeaurora.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>
2011-03-22 17:44:12 -07:00
Phil Carmody
191e56880a calibrate: home in on correct lpj value more quickly
Binary chop with a jiffy-resync on each step to find an upper bound is
slow, so just race in a tight-ish loop to find an underestimate.

If done with lots of individual steps, sometimes several hundreds of
iterations would be required, which would impose a significant overhead,
and make the initial estimate very low.  By taking slowly increasing steps
there will be less overhead.

E.g.  an x86_64 2.67GHz could have fitted in 613 individual small delays,
but in reality should have been able to fit in a single delay 644 times
longer, so underestimated by 31 steps.  To reach the equivalent of 644
small delays with the accelerating scheme now requires about 130
iterations, so has <1/4th of the overhead, and can therefore be expected
to underestimate by only 7 steps.

As now we have a better initial estimate we can binary chop over a smaller
range.  With the loop overhead in the initial estimate kept low, and the
step sizes moderate, we won't have under-estimated by much, so chose as
tight a range as we can.

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Tested-by: Stephen Boyd <sboyd@codeaurora.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>
2011-03-22 17:44:11 -07:00
Phil Carmody
71c696b1d0 calibrate: extract fall-back calculation into own helper
The motivation for this patch series is that currently our OMAP calibrates
itself using the trial-and-error binary chop fallback that some other
architectures no longer need to perform.  This is a lengthy process,
taking 0.2s in an environment where boot time is of great interest.

Patch 2/4 has two optimisations.  Firstly, it replaces the initial
repeated- doubling to find the relevant power of 2 with a tight loop that
just does as much as it can in a jiffy.  Secondly, it doesn't binary chop
over an entire power of 2 range, it choses a much smaller range based on
how much it squeezed in, and failed to squeeze in, during the first stage.
 Both are significant optimisations, and bring our calibration down from
23 jiffies to 5, and, in the process, often arrive at a more accurate lpj
value.

The 'bands' and 'sub-logarithmic' growth may look over-engineered, but
they only cost a small level of inaccuracy in the initial guess (for all
architectures) in order to avoid the very large inaccuracies that appeared
during testing (on x86_64 architectures, and presumably others with less
metronomic operation).  Note that due to the existence of the TSC and
other timers, the x86_64 will not typically use this fallback routine, but
I wanted to code defensively, able to cope with all kinds of processor
behaviours and kernel command line options.

Patch 3/4 is an additional trap for the nightmare scenario where the
initial estimate is very inaccurate, possibly due to things like SMIs.
It simply retries with a larger bound.

Stephen said:

I tried this patch set out on an MSM7630.
:
: Before:
:
: Calibrating delay loop... 681.57 BogoMIPS (lpj=3407872)
:
: After:
:
: Calibrating delay loop... 680.75 BogoMIPS (lpj=3403776)
:
: But the really good news is calibration time dropped from ~247ms to ~56ms.
:  Sadly we won't be able to benefit from this should my udelay patches make
: it into ARM because we would be using calibrate_delay_direct() instead (at
: least on machines who choose to).  Can we somehow reapply the logic behind
: this to calibrate_delay_direct()?  That would be even better, but this is
: definitely a boot time improvement.
:
: Or maybe we could just replace calibrate_delay_direct() with this fallback
: calculation?  If __delay() is a thin wrapper around read_current_timer()
: it should work just as well (plus patch 3 makes it handle SMIs).  I'll try
: that out.

This patch:

... so that it can be modified more clinically.

This is almost entirely cosmetic. The only change to the operation
is that the global variable is only set once after the estimation is
completed, rather than taking on all the intermediate values. However,
there are no readers of that variable, so this change is unimportant.

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Tested-by: Stephen Boyd <sboyd@codeaurora.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>
2011-03-22 17:44:11 -07:00
Amerigo Wang
34db18a054 smp: move smp setup functions to kernel/smp.c
Move setup_nr_cpu_ids(), smp_init() and some other SMP boot parameter
setup functions from init/main.c to kenrel/smp.c, saves some #ifdef
CONFIG_SMP.

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Rakib Mullick <rakib.mullick@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
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>
2011-03-22 17:44:11 -07:00
Mandeep Singh Baines
80cdc6dae7 fs: use appropriate printk priority levels
printk()s without a priority level default to KERN_WARNING.  To reduce
noise at KERN_WARNING, this patch set the priority level appriopriately
for unleveled printks()s.  This should be useful to folks that look at
dmesg warnings closely.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
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>
2011-03-22 17:44:10 -07:00
Linus Torvalds
e16b396ce3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (47 commits)
  doc: CONFIG_UNEVICTABLE_LRU doesn't exist anymore
  Update cpuset info & webiste for cgroups
  dcdbas: force SMI to happen when expected
  arch/arm/Kconfig: remove one to many l's in the word.
  asm-generic/user.h: Fix spelling in comment
  drm: fix printk typo 'sracth'
  Remove one to many n's in a word
  Documentation/filesystems/romfs.txt: fixing link to genromfs
  drivers:scsi Change printk typo initate -> initiate
  serial, pch uart: Remove duplicate inclusion of linux/pci.h header
  fs/eventpoll.c: fix spelling
  mm: Fix out-of-date comments which refers non-existent functions
  drm: Fix printk typo 'failled'
  coh901318.c: Change initate to initiate.
  mbox-db5500.c Change initate to initiate.
  edac: correct i82975x error-info reported
  edac: correct i82975x mci initialisation
  edac: correct commented info
  fs: update comments to point correct document
  target: remove duplicate include of target/target_core_device.h from drivers/target/target_core_hba.c
  ...

Trivial conflict in fs/eventpoll.c (spelling vs addition)
2011-03-18 10:37:40 -07:00
Linus Torvalds
f74b944419 Merge branch 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  BKL: That's all, folks
  fs/locks.c: Remove stale FIXME left over from BKL conversion
  ipx: remove the BKL
  appletalk: remove the BKL
  x25: remove the BKL
  ufs: remove the BKL
  hpfs: remove the BKL
  drivers: remove extraneous includes of smp_lock.h
  tracing: don't trace the BKL
  adfs: remove the big kernel lock
2011-03-16 17:21:00 -07:00
Linus Torvalds
a5e6b135bd Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (50 commits)
  printk: do not mangle valid userspace syslog prefixes
  efivars: Add Documentation
  efivars: Expose efivars functionality to external drivers.
  efivars: Parameterize operations.
  efivars: Split out variable registration
  efivars: parameterize efivars
  efivars: Make efivars bin_attributes dynamic
  efivars: move efivars globals into struct efivars
  drivers:misc: ti-st: fix debugging code
  kref: Fix typo in kref documentation
  UIO: add PRUSS UIO driver support
  Fix spelling mistakes in Documentation/zh_CN/SubmittingPatches
  firmware: Fix unaligned memory accesses in dmi-sysfs
  firmware: Add documentation for /sys/firmware/dmi
  firmware: Expose DMI type 15 System Event Log
  firmware: Break out system_event_log in dmi-sysfs
  firmware: Basic dmi-sysfs support
  firmware: Add DMI entry types to the headers
  Driver core: convert platform_{get,set}_drvdata to static inline functions
  Translate linux-2.6/Documentation/magic-number.txt into Chinese
  ...
2011-03-16 15:05:40 -07:00
Linus Torvalds
a926021cb1 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (184 commits)
  perf probe: Clean up probe_point_lazy_walker() return value
  tracing: Fix irqoff selftest expanding max buffer
  tracing: Align 4 byte ints together in struct tracer
  tracing: Export trace_set_clr_event()
  tracing: Explain about unstable clock on resume with ring buffer warning
  ftrace/graph: Trace function entry before updating index
  ftrace: Add .ref.text as one of the safe areas to trace
  tracing: Adjust conditional expression latency formatting.
  tracing: Fix event alignment: skb:kfree_skb
  tracing: Fix event alignment: mce:mce_record
  tracing: Fix event alignment: kvm:kvm_hv_hypercall
  tracing: Fix event alignment: module:module_request
  tracing: Fix event alignment: ftrace:context_switch and ftrace:wakeup
  tracing: Remove lock_depth from event entry
  perf header: Stop using 'self'
  perf session: Use evlist/evsel for managing perf.data attributes
  perf top: Don't let events to eat up whole header line
  perf top: Fix events overflow in top command
  ring-buffer: Remove unused #include <linux/trace_irq.h>
  tracing: Add an 'overwrite' trace_option.
  ...
2011-03-15 18:31:30 -07:00
Aneesh Kumar K.V
990d6c2d7a vfs: Add name to file handle conversion support
The syscall also return mount id which can be used
to lookup file system specific information such as uuid
in /proc/<pid>/mountinfo

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-15 02:21:37 -04:00
Arnd Bergmann
4ba8216cd9 BKL: That's all, folks
This removes the implementation of the big kernel lock,
at last. A lot of people have worked on this in the
past, I so the credit for this patch should be with
everyone who participated in the hunt.

The names on the Cc list are the people that were the
most active in this, according to the recorded git
history, in alphabetical order.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Cc: Alessio Igor Bogani <abogani@texware.it>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Hendry <andrew.hendry@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Jan Blunck <jblunck@infradead.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Paul Menage <menage@google.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-05 10:56:00 +01:00
Li Zefan
2d0f25201e perf cgroup: Fix a typo in kernel config
s/specificied/specified

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4D6F348C.2050804@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-04 11:32:51 +01:00
Stephane Eranian
e5d1367f17 perf: Add cgroup support
This kernel patch adds the ability to filter monitoring based on
container groups (cgroups). This is for use in per-cpu mode only.

The cgroup to monitor is passed as a file descriptor in the pid
argument to the syscall. The file descriptor must be opened to
the cgroup name in the cgroup filesystem. For instance, if the
cgroup name is foo and cgroupfs is mounted in /cgroup, then the
file descriptor is opened to /cgroup/foo. Cgroup mode is
activated by passing PERF_FLAG_PID_CGROUP in the flags argument
to the syscall.

For instance to measure in cgroup foo on CPU1 assuming
cgroupfs is mounted under /cgroup:

struct perf_event_attr attr;
int cgroup_fd, fd;

cgroup_fd = open("/cgroup/foo", O_RDONLY);
fd = perf_event_open(&attr, cgroup_fd, 1, -1, PERF_FLAG_PID_CGROUP);
close(cgroup_fd);

Signed-off-by: Stephane Eranian <eranian@google.com>
[ added perf_cgroup_{exit,attach} ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4d590250.114ddf0a.689e.4482@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-16 13:30:48 +01:00
Jiri Kosina
0a9d59a246 Merge branch 'master' into for-next 2011-02-15 10:24:31 +01:00
Tim Deegan
70a062286b fix jiffy calculations in calibrate_delay_direct to handle overflow
Fixes a hang when booting as dom0 under Xen, when jiffies can be
quite large by the time the kernel init gets this far.

Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com>
[jbeulich@novell.com: !time_after() -> time_before_eq() as suggested by Jiri Slaby]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-10 11:00:09 -08:00
Ferenc Wagner
5d6a4ea576 sysfs: Capitalize description of SYSFS_DEPRECATED{_V2} options
Signed-off-by: Ferenc Wagner <wferi@niif.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-03 16:36:40 -08:00
Linus Torvalds
2b1caf6ed7 Merge branch 'core-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:
  smp: Allow on_each_cpu() to be called while early_boot_irqs_disabled status to init/main.c
  lockdep: Move early boot local IRQ enable/disable status to init/main.c
2011-01-20 18:30:37 -08:00
David Rientjes
6a108a14fa kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT
The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel.  A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.

Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: David Woodhouse <david.woodhouse@intel.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-20 17:02:05 -08:00
Tejun Heo
2ce802f62b lockdep: Move early boot local IRQ enable/disable status to init/main.c
During early boot, local IRQ is disabled until IRQ subsystem is
properly initialized.  During this time, no one should enable
local IRQ and some operations which usually are not allowed with
IRQ disabled, e.g. operations which might sleep or require
communications with other processors, are allowed.

lockdep tracked this with early_boot_irqs_off/on() callbacks.
As other subsystems need this information too, move it to
init/main.c and make it generally available.  While at it,
toggle the boolean to early_boot_irqs_disabled instead of
enabled so that it can be initialized with %false and %true
indicates the exceptional condition.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20110120110635.GB6036@htj.dyndns.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-20 13:32:33 +01:00
Michael Witten
c5e0591ae3 Kconfig: BLK_THROTTLE -> BLK_DEV_THROTTLING
It would seem that `CONFIG_BLK_THROTTLE' doesn't exist,
as it is only referenced in the documentation for
`CONFIG_BLK_CGROUP'. The only other choice is
`CONFIG_BLK_DEV_THROTTLING':

  $ git grep --cached THROTTL -- \*Kconfig
  block/Kconfig:config BLK_DEV_THROTTLING
  init/Kconfig:   CONFIG_BLK_THROTTLE=y.

Signed-off-by: Michael Witten <mfwitten@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-01-17 11:15:04 +01:00
Michael Witten
79e2e7597d Kconfig: Typo: seti -> set
Also, I introduced some punctuation to facilitate reading.

Signed-off-by: Michael Witten <mfwitten@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-01-17 11:13:55 +01:00
Linus Torvalds
f9ee7f60d6 Merge branches 'core-fixes-for-linus', 'x86-fixes-for-linus', 'timers-fixes-for-linus' and 'perf-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:
  rcu: avoid pointless blocked-task warnings
  rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
  rtmutex: Fix comment about why new_owner can be NULL in wake_futex_pi()

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, olpc: Add missing Kconfig dependencies
  x86, mrst: Set correct APB timer IRQ affinity for secondary cpu
  x86: tsc: Fix calibration refinement conditionals to avoid divide by zero
  x86, ia64, acpi: Clean up x86-ism in drivers/acpi/numa.c

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timekeeping: Make local variables static
  time: Rename misnamed minsec argument of clocks_calc_mult_shift()

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Remove syscall_exit_fields
  tracing: Only process module tracepoints once
  perf record: Add "nodelay" mode, disabled by default
  perf sched: Fix list of events, dropping unsupported ':r' modifier
  Revert "perf tools: Emit clearer message for sys_perf_event_open ENOENT return"
  perf top: Fix annotate segv
  perf evsel: Fix order of event list deletion
2011-01-15 12:45:00 -08:00
Ingo Molnar
1161ec9449 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/urgent 2011-01-14 15:30:16 +01:00
Paul E. McKenney
c072a388d5 rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
Because the adaptive synchronize_srcu_expedited() approach has
worked very well in testing, remove the kernel parameter and
replace it by a C-preprocessor macro.  If someone finds problems
with this approach, a more complex and aggressively adaptive
approach might be required.

Longer term, SRCU will be merged with the other RCU implementations,
at which point synchronize_srcu_expedited() will be event driven,
just as synchronize_sched_expedited() currently is.  At that point,
there will be no need for this adaptive approach.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-01-14 04:56:49 -08:00
Linus Torvalds
008d23e485 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
  Documentation/trace/events.txt: Remove obsolete sched_signal_send.
  writeback: fix global_dirty_limits comment runtime -> real-time
  ppc: fix comment typo singal -> signal
  drivers: fix comment typo diable -> disable.
  m68k: fix comment typo diable -> disable.
  wireless: comment typo fix diable -> disable.
  media: comment typo fix diable -> disable.
  remove doc for obsolete dynamic-printk kernel-parameter
  remove extraneous 'is' from Documentation/iostats.txt
  Fix spelling milisec -> ms in snd_ps3 module parameter description
  Fix spelling mistakes in comments
  Revert conflicting V4L changes
  i7core_edac: fix typos in comments
  mm/rmap.c: fix comment
  sound, ca0106: Fix assignment to 'channel'.
  hrtimer: fix a typo in comment
  init/Kconfig: fix typo
  anon_inodes: fix wrong function name in comment
  fix comment typos concerning "consistent"
  poll: fix a typo in comment
  ...

Fix up trivial conflicts in:
 - drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c)
 - fs/ext4/ext4.h

Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
2011-01-13 10:05:56 -08:00
Lasse Collin
3ebe12439b decompressors: add boot-time XZ support
This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression.  This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.

The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).

The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments.  I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:25 -08:00
Linus Torvalds
23d69b09b7 Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (33 commits)
  usb: don't use flush_scheduled_work()
  speedtch: don't abuse struct delayed_work
  media/video: don't use flush_scheduled_work()
  media/video: explicitly flush request_module work
  ioc4: use static work_struct for ioc4_load_modules()
  init: don't call flush_scheduled_work() from do_initcalls()
  s390: don't use flush_scheduled_work()
  rtc: don't use flush_scheduled_work()
  mmc: update workqueue usages
  mfd: update workqueue usages
  dvb: don't use flush_scheduled_work()
  leds-wm8350: don't use flush_scheduled_work()
  mISDN: don't use flush_scheduled_work()
  macintosh/ams: don't use flush_scheduled_work()
  vmwgfx: don't use flush_scheduled_work()
  tpm: don't use flush_scheduled_work()
  sonypi: don't use flush_scheduled_work()
  hvsi: don't use flush_scheduled_work()
  xen: don't use flush_scheduled_work()
  gdrom: don't use flush_scheduled_work()
  ...

Fixed up trivial conflict in drivers/media/video/bt8xx/bttv-input.c
as per Tejun.
2011-01-07 16:58:04 -08:00
Linus Torvalds
65b2074f84 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (30 commits)
  sched: Change wait_for_completion_*_timeout() to return a signed long
  sched, autogroup: Fix reference leak
  sched, autogroup: Fix potential access to freed memory
  sched: Remove redundant CONFIG_CGROUP_SCHED ifdef
  sched: Fix interactivity bug by charging unaccounted run-time on entity re-weight
  sched: Move periodic share updates to entity_tick()
  printk: Use this_cpu_{read|write} api on printk_pending
  sched: Make pushable_tasks CONFIG_SMP dependant
  sched: Add 'autogroup' scheduling feature: automated per session task groups
  sched: Fix unregister_fair_sched_group()
  sched: Remove unused argument dest_cpu to migrate_task()
  mutexes, sched: Introduce arch_mutex_cpu_relax()
  sched: Add some clock info to sched_debug
  cpu: Remove incorrect BUG_ON
  cpu: Remove unused variable
  sched: Fix UP build breakage
  sched: Make task dump print all 15 chars of proc comm
  sched: Update tg->shares after cpu.shares write
  sched: Allow update_cfs_load() to update global load
  sched: Implement demand based update_cfs_load()
  ...
2011-01-06 10:23:33 -08:00
Linus Torvalds
28d9bfc37c Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (146 commits)
  tools, perf: Documentation for the power events API
  perf: Add calls to suspend trace point
  perf script: Make some lists static
  perf script: Use the default lost event handler
  perf session: Warn about errors when processing pipe events too
  perf tools: Fix perf_event.h header usage
  perf test: Clarify some error reports in the open syscall test
  x86, NMI: Add touch_nmi_watchdog to io_check_error delay
  x86: Avoid calling arch_trigger_all_cpu_backtrace() at the same time
  x86: Only call smp_processor_id in non-preempt cases
  perf timechart: Adjust perf timechart to the new power events
  perf: Clean up power events by introducing new, more generic ones
  perf: Do not export power_frequency, but power_start event
  perf test: Add test for counting open syscalls
  perf evsel: Auto allocate resources needed for some methods
  perf evsel: Use {cpu,thread}_map to shorten list of parameters
  perf tools: Refactor all_tids to hold nr and the map
  perf tools: Refactor cpumap to hold nr and the map
  perf evsel: Introduce per cpu and per thread open helpers
  perf evsel: Steal the counter reading routines from stat
  ...
2011-01-06 10:17:26 -08:00
Linus Torvalds
2af49b6058 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: remove unused __list_for_each_rcu() macro
  rculist: fix borked __list_for_each_rcu() macro
  rcu: reduce __call_rcu()-induced contention on rcu_node structures
  rcu: limit rcu_node leaf-level fanout
  rcu: fine-tune grace-period begin/end checks
  rcu: Keep gpnum and completed fields synchronized
  rcu: Stop chasing QS if another CPU did it for us
  rcu: increase synchronize_sched_expedited() batching
  rcu: Make synchronize_srcu_expedited() fast if running readers
  rcu: fix race condition in synchronize_sched_expedited()
  rcu: update documentation/comments for Lai's adoption patch
  rcu,cleanup: simplify the code when cpu is dying
  rcu,cleanup: move synchronize_sched_expedited() out of sched.c
  rcu: get rid of obsolete "classic" names in TREE_RCU tracing
  rcu: Distinguish between boosting and boosted
  rcu: document TINY_RCU and TINY_PREEMPT_RCU tracing.
  rcu: add tracing for TINY_RCU and TINY_PREEMPT_RCU
  rcu: priority boosting for TINY_PREEMPT_RCU
  rcu: move TINY_RCU from softirq to kthread
  rcu: add priority-inversion testing to rcutorture
2011-01-06 10:06:26 -08:00
Ingo Molnar
aef1b9cef7 Merge commit 'v2.6.37' into perf/core
Merge reason: Add the final .37 tree.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-05 14:22:10 +01:00
Ingo Molnar
27066fd484 Merge commit 'v2.6.37' into sched/core
Merge reason: Merge the final .37 tree.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-05 14:14:46 +01:00
Jan Beulich
a1cf11d8f6 name_to_dev_t() must not call __init code
The function can't be __init itself (being called from some sysfs
handler), and hence none of the functions it calls can be either.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-03 11:48:11 -08:00
Tejun Heo
ee4569a3a7 init: don't call flush_scheduled_work() from do_initcalls()
The call to flush_scheduled_work() in do_initcalls() is there to make
sure all works queued to system_wq by initcalls finish before the init
sections are dropped.

However, the call doesn't make much sense at this point - there
already are multiple different workqueues and different subsystems are
free to create and use their own.  Ordering requirements are and
should be expressed explicitly.

Drop the call to prepare for the deprecation and removal of
flush_scheduled_work().

Andrew suggested adding sanity check where the workqueue code checks
whether any pending or running work has the work function in the init
text section.  However, checking this for running works requires the
worker to keep track of the current function being executed, and
checking only the pending works will miss most cases.  As a violation
will almost always be caught by the usual page fault mechanism, I
don't think it would be worthwhile to make the workqueue code track
extra state just for this.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
2010-12-24 16:14:20 +01:00
Ingo Molnar
394f4528c5 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/rcu 2010-12-23 12:57:04 +01:00
Jim Cromie
43d547f9ce init/Kconfig: fix typo
Signed-off-by:  Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-12-22 18:58:36 +01:00
Peter Zijlstra
9f58a205c6 init: Initialized IDR earlier
perf_event_init() wants to start using IDR trees, its needs in turn
are satisfied by mm_init().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20101117222056.206992649@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-16 11:36:43 +01:00
Peter Zijlstra
24a24bb6ff perf: Move perf_event_init() into main.c
Currently we call perf_event_init() from sched_init(). In order to
make it more obvious move it to the cannnonical location.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20101117222056.093629821@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-16 11:36:42 +01:00
Ingo Molnar
8e9255e6a2 Merge branch 'linus' into sched/core
Merge reason: we want to queue up dependent cleanup

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-08 20:15:29 +01:00
Ingo Molnar
10a18d7dc0 Merge commit 'v2.6.37-rc5' into perf/core
Merge reason: Pick up the latest -rc.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-07 07:49:51 +01:00
Mike Galbraith
5091faa449 sched: Add 'autogroup' scheduling feature: automated per session task groups
A recurring complaint from CFS users is that parallel kbuild has
a negative impact on desktop interactivity.  This patch
implements an idea from Linus, to automatically create task
groups.  Currently, only per session autogroups are implemented,
but the patch leaves the way open for enhancement.

Implementation: each task's signal struct contains an inherited
pointer to a refcounted autogroup struct containing a task group
pointer, the default for all tasks pointing to the
init_task_group.  When a task calls setsid(), a new task group
is created, the process is moved into the new task group, and a
reference to the preveious task group is dropped.  Child
processes inherit this task group thereafter, and increase it's
refcount.  When the last thread of a process exits, the
process's reference is dropped, such that when the last process
referencing an autogroup exits, the autogroup is destroyed.

At runqueue selection time, IFF a task has no cgroup assignment,
its current autogroup is used.

Autogroup bandwidth is controllable via setting it's nice level
through the proc filesystem:

  cat /proc/<pid>/autogroup

Displays the task's group and the group's nice level.

  echo <nice level> > /proc/<pid>/autogroup

Sets the task group's shares to the weight of nice <level> task.
Setting nice level is rate limited for !admin users due to the
abuse risk of task group locking.

The feature is enabled from boot by default if
CONFIG_SCHED_AUTOGROUP=y is selected, but can be disabled via
the boot option noautogroup, and can also be turned on/off on
the fly via:

  echo [01] > /proc/sys/kernel/sched_autogroup_enabled

... which will automatically move tasks to/from the root task group.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Paul Turner <pjt@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
[ Removed the task_group_path() debug code, and fixed !EVENTFD build failure. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1290281700.28711.9.camel@maggy.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-30 16:03:35 +01:00
Paul E. McKenney
46fdb0937f rcu: Make synchronize_srcu_expedited() fast if running readers
The synchronize_srcu_expedited() function is currently quick if there
are no active readers, but will delay a full jiffy if there are any.
If these readers leave their SRCU read-side critical sections quickly,
this is way too long to wait.  So this commit first waits ten microseconds,
and only then falls back to jiffy-at-a-time waiting.

Reported-by: Avi Kivity <avi@redhat.com>
Reported-by: Marcelo Tosatti <mtosatti@redhat.com>
Tested-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-11-29 22:02:40 -08:00
Paul E. McKenney
9e571a82f0 rcu: add tracing for TINY_RCU and TINY_PREEMPT_RCU
Add tracing for the tiny RCU implementations, including statistics on
boosting in the case of TINY_PREEMPT_RCU and RCU_BOOST.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-11-29 22:01:55 -08:00
Paul E. McKenney
24278d1483 rcu: priority boosting for TINY_PREEMPT_RCU
Add priority boosting, but only for TINY_PREEMPT_RCU.  This is enabled
by the default-off RCU_BOOST kernel parameter.  The priority to which to
boost preempted RCU readers is controlled by the RCU_BOOST_PRIO kernel
parameter (defaulting to real-time priority 1) and the time to wait
before boosting the readers blocking a given grace period is controlled
by the RCU_BOOST_DELAY kernel parameter (defaulting to 500 milliseconds).

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-11-29 22:01:54 -08:00
Peter Zijlstra
004417a6d4 perf, arch: Cleanup perf-pmu init vs lockup-detector
The perf hardware pmu got initialized at various points in the boot,
some before early_initcall() some after (notably arch_initcall).

The problem is that the NMI lockup detector is ran from early_initcall()
and expects the hardware pmu to be present.

Sanitize this by moving all architecture hardware pmu implementations to
initialize at early_initcall() and move the lockup detector to an explicit
initcall right after that.

Cc: paulus <paulus@samba.org>
Cc: davem <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290707759.2145.119.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-26 15:14:56 +01:00
Michal Hocko
a42c390cfa cgroups: make swap accounting default behavior configurable
Swap accounting can be configured by CONFIG_CGROUP_MEM_RES_CTLR_SWAP
configuration option and then it is turned on by default.  There is a boot
option (noswapaccount) which can disable this feature.

This makes it hard for distributors to enable the configuration option as
this feature leads to a bigger memory consumption and this is a no-go for
general purpose distribution kernel.  On the other hand swap accounting
may be very usuful for some workloads.

This patch adds a new configuration option which controls the default
behavior (CGROUP_MEM_RES_CTLR_SWAP_ENABLED).  If the option is selected
then the feature is turned on by default.

It also adds a new boot parameter swapaccount[=1|0] which enhances the
original noswapaccount parameter semantic by means of enable/disable logic
(defaults to 1 if no value is provided to be still consistent with
noswapaccount).

The default behavior is unchanged (if CONFIG_CGROUP_MEM_RES_CTLR_SWAP is
enabled then CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED is enabled as well)

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.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>
2010-11-25 06:50:45 +09:00
Arnd Bergmann
451a3c24b0 BKL: remove extraneous #include <smp_lock.h>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-17 08:59:32 -08:00
Linus Torvalds
c9e2a72ff1 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  initramfs: Fix build break on symbol-prefixed archs
  initramfs: fix initramfs size calculation
  initramfs: generalize initramfs_data.xxx.S variants
  scripts/kallsyms: Enable error messages while hush up unnecessary warnings
  scripts/setlocalversion: update comment
  kbuild: Use a single clean rule for kernel and external modules
  kbuild: Do not run make clean in $(srctree)
  scripts/mod/modpost.c: fix commentary accordingly to last changes
  kbuild: Really don't clean bounds.h and asm-offsets.h
2010-10-28 15:13:55 -07:00
Daniel Lezcano
7af37bec41 namespaces Kconfig: move namespace menu location after the cgroup
We have the namespaces as a menuconfig like the cgroup.  The cgroup and
the namespace are two base bricks for the containers.

It is more logical to put the namespace menu right after the cgroup menu.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:17 -07:00
Daniel Lezcano
eef691b36e namespaces Kconfig: remove the cgroup device whitelist experimental tag
This subsystem is merged since a long time now, I think we can consider it
mature enough.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:17 -07:00
Daniel Lezcano
79ae9c29e4 namespaces Kconfig: remove pointless cgroup dependency
The different cgroup subsystems are under the cgroup submenu.  The
dependency between the cgroups and the menu subsystems is pointless.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:16 -07:00
Daniel Lezcano
8dd2a82c29 namespaces Kconfig: make namespace a submenu
Make the namespaces config option a submenu.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:16 -07:00
Daniel Lezcano
17a6d4411a namespaces: default all the namespaces to 'yes' when CONFIG_NAMESPACES is selected
As the different namespaces depend on 'CONFIG_NAMESPACES', it is logical
to enable all the namespaces when we enable NAMESPACES.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: David Miller <davem@davemloft.net>
Acked-By: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:16 -07:00
Daniel Lezcano
9bd38c2cda namespaces: remove pid_ns and net_ns experimental status
The pid namespace is in the kernel since 2.6.27 and the net_ns since
2.6.29.  They are enabled in the distro by default and used by userspace
component.  They are mature enough to remove the 'experimental' label.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:16 -07:00
Namhyung Kim
562f5e638d init: mark __user address space on string literals
When calling syscall service routines in kernel, some of arguments should
be user pointers but were missing __user markup on string literals.  Add
it.  Removes some sparse warnings.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:15 -07:00
Linus Torvalds
74eb94b218 Merge branch 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (67 commits)
  SUNRPC: Cleanup duplicate assignment in rpcauth_refreshcred
  nfs: fix unchecked value
  Ask for time_delta during fsinfo probe
  Revalidate caches on lock
  SUNRPC: After calling xprt_release(), we must restart from call_reserve
  NFSv4: Fix up the 'dircount' hint in encode_readdir
  NFSv4: Clean up nfs4_decode_dirent
  NFSv4: nfs4_decode_dirent must clear entry->fattr->valid
  NFSv4: Fix a regression in decode_getfattr
  NFSv4: Fix up decode_attr_filehandle() to handle the case of empty fh pointer
  NFS: Ensure we check all allocation return values in new readdir code
  NFS: Readdir plus in v4
  NFS: introduce generic decode_getattr function
  NFS: check xdr_decode for errors
  NFS: nfs_readdir_filler catch all errors
  NFS: readdir with vmapped pages
  NFS: remove page size checking code
  NFS: decode_dirent should use an xdr_stream
  SUNRPC: Add a helper function xdr_inline_peek
  NFS: remove readdir plus limit
  ...
2010-10-25 13:48:29 -07:00
Linus Torvalds
229aebb873 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
  Update broken web addresses in arch directory.
  Update broken web addresses in the kernel.
  Revert "drivers/usb: Remove unnecessary return's from void functions" for musb gadget
  Revert "Fix typo: configuation => configuration" partially
  ida: document IDA_BITMAP_LONGS calculation
  ext2: fix a typo on comment in ext2/inode.c
  drivers/scsi: Remove unnecessary casts of private_data
  drivers/s390: Remove unnecessary casts of private_data
  net/sunrpc/rpc_pipe.c: Remove unnecessary casts of private_data
  drivers/infiniband: Remove unnecessary casts of private_data
  drivers/gpu/drm: Remove unnecessary casts of private_data
  kernel/pm_qos_params.c: Remove unnecessary casts of private_data
  fs/ecryptfs: Remove unnecessary casts of private_data
  fs/seq_file.c: Remove unnecessary casts of private_data
  arm: uengine.c: remove C99 comments
  arm: scoop.c: remove C99 comments
  Fix typo configue => configure in comments
  Fix typo: configuation => configuration
  Fix typo interrest[ing|ed] => interest[ing|ed]
  Fix various typos of valid in comments
  ...

Fix up trivial conflicts in:
	drivers/char/ipmi/ipmi_si_intf.c
	drivers/usb/gadget/rndis.c
	net/irda/irnet/irnet_ppp.c
2010-10-24 13:41:39 -07:00
Linus Torvalds
b9da057105 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (31 commits)
  driver core: Display error codes when class suspend fails
  Driver core: Add section count to memory_block struct
  Driver core: Add mutex for adding/removing memory blocks
  Driver core: Move find_memory_block routine
  hpilo: Despecificate driver from iLO generation
  driver core: Convert link_mem_sections to use find_memory_block_hinted.
  driver core: Introduce find_memory_block_hinted which utilizes kset_find_obj_hinted.
  kobject: Introduce kset_find_obj_hinted.
  driver core: fix build for CONFIG_BLOCK not enabled
  driver-core: base: change to new flag variable
  sysfs: only access bin file vm_ops with the active lock
  sysfs: Fail bin file mmap if vma close is implemented.
  FW_LOADER: fix kconfig dependency warning on HOTPLUG
  uio: Statically allocate uio_class and use class .dev_attrs.
  uio: Support 2^MINOR_BITS minors
  uio: Cleanup irq handling.
  uio: Don't clear driver data
  uio: Fix lack of locking in init_uio_class
  SYSFS: Allow boot time switching between deprecated and modern sysfs layout
  driver core: remove CONFIG_SYSFS_DEPRECATED_V2 but keep it for block devices
  ...
2010-10-22 19:36:42 -07:00
Linus Torvalds
e9dd2b6837 Merge branch 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block: (39 commits)
  cfq-iosched: Fix a gcc 4.5 warning and put some comments
  block: Turn bvec_k{un,}map_irq() into static inline functions
  block: fix accounting bug on cross partition merges
  block: Make the integrity mapped property a bio flag
  block: Fix double free in blk_integrity_unregister
  block: Ensure physical block size is unsigned int
  blkio-throttle: Fix possible multiplication overflow in iops calculations
  blkio-throttle: limit max iops value to UINT_MAX
  blkio-throttle: There is no need to convert jiffies to milli seconds
  blkio-throttle: Fix link failure failure on i386
  blkio: Recalculate the throttled bio dispatch time upon throttle limit change
  blkio: Add root group to td->tg_list
  blkio: deletion of a cgroup was causes oops
  blkio: Do not export throttle files if CONFIG_BLK_DEV_THROTTLING=n
  block: set the bounce_pfn to the actual DMA limit rather than to max memory
  block: revert bad fix for memory hotplug causing bounces
  Fix compile error in blk-exec.c for !CONFIG_DETECT_HUNG_TASK
  block: set the bounce_pfn to the actual DMA limit rather than to max memory
  block: Prevent hang_check firing during long I/O
  cfq: improve fsync performance for small files
  ...

Fix up trivial conflicts due to __rcu sparse annotation in include/linux/genhd.h
2010-10-22 17:00:32 -07:00
Linus Torvalds
5704e44d28 Merge branch 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  BKL: introduce CONFIG_BKL.
  dabusb: remove the BKL
  sunrpc: remove the big kernel lock
  init/main.c: remove BKL notations
  blktrace: remove the big kernel lock
  rtmutex-tester: make it build without BKL
  dvb-core: kill the big kernel lock
  dvb/bt8xx: kill the big kernel lock
  tlclk: remove big kernel lock
  fix rawctl compat ioctls breakage on amd64 and itanic
  uml: kill big kernel lock
  parisc: remove big kernel lock
  cris: autoconvert trivial BKL users
  alpha: kill big kernel lock
  isapnp: BKL removal
  s390/block: kill the big kernel lock
  hpet: kill BKL, add compat_ioctl
2010-10-22 10:43:11 -07:00
Andi Kleen
e52eec13cd SYSFS: Allow boot time switching between deprecated and modern sysfs layout
I have some systems which need legacy sysfs due to old tools that are
making assumptions that a directory can never be a symlink to another
directory, and it's a big hazzle to compile separate kernels for them.

This patch turns CONFIG_SYSFS_DEPRECATED into a run time option
that can be switched on/off the kernel command line. This way
the same binary can be used in both cases with just a option
on the command line.

The old CONFIG_SYSFS_DEPRECATED_V2 option is still there to set
the default. I kept the weird name to not break existing
config files.

Also the compat code can be still completely disabled by undefining
CONFIG_SYSFS_DEPRECATED_SWITCH -- just the optimizer takes
care of this now instead of lots of ifdefs. This makes the code
look nicer.

v2: This is an updated version on top of Kay's patch to only
handle the block devices. I tested it on my old systems
and that seems to work.

Cc: axboe@kernel.dk
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22 10:16:43 -07:00
Kay Sievers
39aba963d9 driver core: remove CONFIG_SYSFS_DEPRECATED_V2 but keep it for block devices
This patch removes the old CONFIG_SYSFS_DEPRECATED_V2 config option,
but it keeps the logic around to handle block devices in the old manner
as some people like to run new kernel versions on old (pre 2007/2008)
distros.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: "James E.J. Bottomley" <James.Bottomley@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22 10:16:43 -07:00
Linus Torvalds
4a60cfa945 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (96 commits)
  apic, x86: Use BIOS settings for IBS and MCE threshold interrupt LVT offsets
  apic, x86: Check if EILVT APIC registers are available (AMD only)
  x86: ioapic: Call free_irte only if interrupt remapping enabled
  arm: Use ARCH_IRQ_INIT_FLAGS
  genirq, ARM: Fix boot on ARM platforms
  genirq: Fix CONFIG_GENIRQ_NO_DEPRECATED=y build
  x86: Switch sparse_irq allocations to GFP_KERNEL
  genirq: Switch sparse_irq allocator to GFP_KERNEL
  genirq: Make sparse_lock a mutex
  x86: lguest: Use new irq allocator
  genirq: Remove the now unused sparse irq leftovers
  genirq: Sanitize dynamic irq handling
  genirq: Remove arch_init_chip_data()
  x86: xen: Sanitise sparse_irq handling
  x86: Use sane enumeration
  x86: uv: Clean up the direct access to irq_desc
  x86: Make io_apic.c local functions static
  genirq: Remove irq_2_iommu
  x86: Speed up the irq_remapped check in hot pathes
  intr_remap: Simplify the code further
  ...

Fix up trivial conflicts in arch/x86/Kconfig
2010-10-21 14:11:46 -07:00
Linus Torvalds
5d70f79b5e Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (163 commits)
  tracing: Fix compile issue for trace_sched_wakeup.c
  [S390] hardirq: remove pointless header file includes
  [IA64] Move local_softirq_pending() definition
  perf, powerpc: Fix power_pmu_event_init to not use event->ctx
  ftrace: Remove recursion between recordmcount and scripts/mod/empty
  jump_label: Add COND_STMT(), reducer wrappery
  perf: Optimize sw events
  perf: Use jump_labels to optimize the scheduler hooks
  jump_label: Add atomic_t interface
  jump_label: Use more consistent naming
  perf, hw_breakpoint: Fix crash in hw_breakpoint creation
  perf: Find task before event alloc
  perf: Fix task refcount bugs
  perf: Fix group moving
  irq_work: Add generic hardirq context callbacks
  perf_events: Fix transaction recovery in group_sched_in()
  perf_events: Fix bogus AMD64 generic TLB events
  perf_events: Fix bogus context time tracking
  tracing: Remove parent recording in latency tracer graph options
  tracing: Use one prologue for the preempt irqs off tracer function tracers
  ...
2010-10-21 12:54:49 -07:00
Arnd Bergmann
6de5bd128d BKL: introduce CONFIG_BKL.
With all the patches we have queued in the BKL removal tree, only a
few dozen modules are left that actually rely on the BKL, and even
there are lots of low-hanging fruit. We need to decide what to do
about them, this patch illustrates one of the options:

Every user of the BKL is marked as 'depends on BKL' in Kconfig,
and the CONFIG_BKL becomes a user-visible option. If it gets
disabled, no BKL using module can be built any more and the BKL
code itself is compiled out.

The one exception is file locking, which is practically always
enabled and does a 'select BKL' instead. This effectively forces
CONFIG_BKL to be enabled until we have solved the fs/lockd
mess and can apply the patch that removes the BKL from fs/locks.c.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-21 15:44:13 +02:00
Namhyung Kim
1fa4f3b57c init/main.c: remove BKL notations
According to commit 5e3d20a68f
(init: Remove the BKL from startup code) these sparse notations
should be removed also.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-19 11:29:58 +02:00
Peter Zijlstra
e360adbe29 irq_work: Add generic hardirq context callbacks
Provide a mechanism that allows running code in IRQ context. It is
most useful for NMI code that needs to interact with the rest of the
system -- like wakeup a task to drain buffers.

Perf currently has such a mechanism, so extract that and provide it as
a generic feature, independent of perf so that others may also
benefit.

The IRQ context callback is generated through self-IPIs where
possible, or on architectures like powerpc the decrementer (the
built-in timer facility) is set to generate an interrupt immediately.

Architectures that don't have anything like this get to do with a
callback from the timer tick. These architectures can call
irq_work_run() at the tail of any IRQ handlers that might enqueue such
work (like the perf IRQ handler) to avoid undue latencies in
processing the work.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[ various fixes ]
Signed-off-by: Huang Ying <ying.huang@intel.com>
LKML-Reference: <1287036094.7768.291.camel@yhuang-dev>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-18 19:58:50 +02:00
Thomas Gleixner
154cd387cd genirq: Remove early_init_irq_lock_class()
early_init_irq_lock_class() is called way before anything touches the
irq descriptors. In case of SPARSE_IRQ=y this is a NOP operation
because the radix tree is empty at this point. For the SPARSE_IRQ=n
case it's sufficient to set the lock class in early_init_irq(). 

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:39:06 +02:00
Thomas Gleixner
d9817ebeee genirq: Provide Kconfig
The generic irq Kconfig options are copied around all archs. Provide a
generic Kconfig file which can be included.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20100927121843.217333624@linutronix.de>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-04 11:01:05 +02:00
Hendrik Brueckner
ffe8018c34 initramfs: fix initramfs size calculation
The size of a built-in initramfs is calculated in init/initramfs.c by
"__initramfs_end - __initramfs_start".  Those symbols are defined in the
linker script include/asm-generic/vmlinux.lds.h:

#define INIT_RAM_FS                                                     \
        . = ALIGN(PAGE_SIZE);                                           \
        VMLINUX_SYMBOL(__initramfs_start) = .;                          \
        *(.init.ramfs)                                                  \
        VMLINUX_SYMBOL(__initramfs_end) = .;

If the initramfs file has an odd number of bytes, the "__initramfs_end"
symbol points to an odd address, for example, the symbols in the
System.map might look like:

    0000000000572000 T __initramfs_start
    00000000005bcd05 T __initramfs_end	  <-- odd address

At least on s390 this causes a problem:

Certain s390 instructions, especially instructions for loading addresses
(larl) or branch addresses must be on even addresses.  The compiler loads
the symbol addresses with the "larl" instruction.  This instruction sets
the last bit to 0 and, therefore, for odd size files, the calculated size
is one byte less than it should be:

    0000000000540a9c <populate_rootfs>:
      540a9c:     eb cf f0 78 00 24       stmg    %r12,%r15,120(%r15),
      540aa2:     c0 10 00 01 8a af       larl    %r1,572000 <__initramfs_start>
      540aa8:     c0 c0 00 03 e1 2e       larl    %r12,5bcd04 <initramfs_end>
                                                  (Instead of  5bcd05)
      ...
      540abe:     1b c1                   sr      %r12,%r1

To fix the problem, this patch introduces the global variable
__initramfs_size, which is calculated in the "usr/initramfs_data.S" file.
The populate_rootfs() function can then use the start marker of the
.init.ramfs section and the value of __initramfs_size for loading the
initramfs.  Because the start marker and size is sufficient, the
__initramfs_end symbol is no longer needed and is removed.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-09-29 16:28:59 +02:00
Chuck Lever
56463e50d1 NFS: Use super.c for NFSROOT mount option parsing
Replace duplicate code in NFSROOT for mounting an NFS server on '/'
with logic that uses the existing mainline text-based logic in the NFS
client.

Add documenting comments where appropriate.

Note that this means NFSROOT mounts now use the same default settings
as v2/v3 mounts done via mount(2) from user space.

  vers=3,tcp,rsize=<negotiated default>,wsize=<negotiated default>

As before, however, no version/protocol negotiation with the server is
done.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-17 10:54:37 -04:00
Jens Axboe
6d0aed7a38 do_mounts: only enable PARTUUID for CONFIG_BLOCK
When CONFIG_BLOCK is not enabled:

init/do_mounts.c:71: error: implicit declaration of function 'dev_to_part'
init/do_mounts.c:71: warning: initialization makes pointer from integer without a cast
init/do_mounts.c:73: error: dereferencing pointer to incomplete type
init/do_mounts.c:76: error: dereferencing pointer to incomplete type
init/do_mounts.c:76: error: dereferencing pointer to incomplete type
init/do_mounts.c:102: error: implicit declaration of function 'part_pack_uuid'
init/do_mounts.c:104: error: 'block_class' undeclared (first use in this function)

Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-17 10:00:46 +02:00
Vivek Goyal
e43473b7f2 blkio: Core implementation of throttle policy
o Actual implementation of throttling policy in block layer. Currently it
  implements READ and WRITE bytes per second throttling logic. IOPS throttling
  comes in later patches.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:42:52 +02:00
Jens Axboe
38b6f45a97 core: match_dev_by_uuid() should not be marked __init
It is also called outside the scope of init functions. Stephen
reports:

WARNING: init/mounts.o(.text+0x21a): Section mismatch in reference from the function name_to_dev_t() to the function .init.text:match_dev_by_uuid()
The function name_to_dev_t() references
the function __init match_dev_by_uuid().
This is often because name_to_dev_t lacks a __init
annotation or the annotation of match_dev_by_uuid is wrong.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 08:33:54 +02:00