334 Commits

Author SHA1 Message Date
Mathieu Desnoyers
551d55a944 tree/tiny rcu: Add debug RCU head objects
Helps finding racy users of call_rcu(), which results in hangs because list
entries are overwritten and/or skipped.

Changelog since v4:
- Bissectability is now OK
- Now generate a WARN_ON_ONCE() for non-initialized rcu_head passed to
  call_rcu(). Statically initialized objects are detected with
  object_is_static().
- Rename rcu_head_init_on_stack to init_rcu_head_on_stack.
- Remove init_rcu_head() completely.

Changelog since v3:
- Include comments from Lai Jiangshan

This new patch version is based on the debugobjects with the newly introduced
"active state" tracker.

Non-initialized entries are all considered as "statically initialized". An
activation fixup (triggered by call_rcu()) takes care of performing the debug
object initialization without issuing any warning. Since we cannot increase the
size of struct rcu_head, I don't see much room to put an identifier for
statically initialized rcu_head structures. So for now, we have to live without
"activation without explicit init" detection. But the main purpose of this debug
option is to detect double-activations (double call_rcu() use of a rcu_head
before the callback is executed), which is correctly addressed here.

This also detects potential internal RCU callback corruption, which would cause
the callbacks to be executed twice.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: David S. Miller <davem@davemloft.net>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: akpm@linux-foundation.org
CC: mingo@elte.hu
CC: laijs@cn.fujitsu.com
CC: dipankar@in.ibm.com
CC: josh@joshtriplett.org
CC: dvhltc@us.ibm.com
CC: niv@us.ibm.com
CC: tglx@linutronix.de
CC: peterz@infradead.org
CC: rostedt@goodmis.org
CC: Valdis.Kletnieks@vt.edu
CC: dhowells@redhat.com
CC: eric.dumazet@gmail.com
CC: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2010-06-14 16:37:26 -07:00
Akinobu Mita
c9d221f86e fault-injection: add CPU notifier error injection module
I used this module to test the series of modification to the cpu notifiers
code.

Example1: inject CPU offline error (-1 == -EPERM)

	# modprobe cpu-notifier-error-inject cpu_down_prepare_error=-1
	# echo 0 > /sys/devices/system/cpu/cpu1/online
	bash: echo: write error: Operation not permitted

Example2: inject CPU online error (-2 == -ENOENT)

	# modprobe cpu-notifier-error-inject cpu_up_prepare_error=-2
	# echo 1 > /sys/devices/system/cpu/cpu1/online
	bash: echo: write error: No such file or directory

[akpm@linux-foundation.org: fix Kconfig help text]
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:48 -07:00
Florian Ragwitz
2b2f68b538 DYNAMIC_DEBUG: fix documentation errors
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Florian Ragwitz <rafl@debian.org>
Cc: Jason Baron <jbaron@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:05 -07:00
Frederic Weisbecker
e35e7fb0e9 lockup_detector: Don't enable the lockup detector by default
The lockup detector is a new feature that now involves the
nmi watchdog. Drop the default y and let the user choose.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
2010-05-19 11:36:49 +02:00
Linus Torvalds
93c9d7f60c Merge branch 'x86-atomic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-atomic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Fix LOCK_PREFIX_HERE for uniprocessor build
  x86, atomic64: In selftest, distinguish x86-64 from 586+
  x86-32: Fix atomic64_inc_not_zero return value convention
  lib: Fix atomic64_inc_not_zero test
  lib: Fix atomic64_add_unless return value convention
  x86-32: Fix atomic64_add_unless return value convention
  lib: Fix atomic64_add_unless test
  x86: Implement atomic[64]_dec_if_positive()
  lib: Only test atomic64_dec_if_positive on archs having it
  x86-32: Rewrite 32-bit atomic64 functions in assembly
  lib: Add self-test for atomic64_t
  x86-32: Allow UP/SMP lock replacement in cmpxchg64
  x86: Add support for lock prefix in alternatives
2010-05-18 08:40:05 -07:00
Frederic Weisbecker
23637d477c lockup_detector: Introduce CONFIG_HARDLOCKUP_DETECTOR
This new config is deemed to simplify even more the lockup detector
dependencies and can make it easier to bring a smooth sorting
between archs that support the new generic lockup detector and those
that still have their own, especially for those that are in the
middle of this migration.

Instead of checking whether we have CONFIG_LOCKUP_DETECTOR +
CONFIG_PERF_EVENTS_NMI each time an arch wants to know if it needs
to build its own lockup detector, take a shortcut with this new
config. It is enabled only if the hardlockup detection part of
the whole lockup detector is on.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
2010-05-16 01:57:42 +02:00
Frederic Weisbecker
e16bb1d7fe lockup_detector: Update some config
We kept CONFIG_DETECT_SOFTLOCKUP around for compatibility with
older configs. But it was enabled by default if CONFIG_DEBUG_KERNEL.

So if we want to enable CONFIG_LOCKUP_DETECTOR on configs that had
CONFIG_DETECT_SOFTLOCKUP, all we need is to have the same enabling
by default if CONFIG_DEBUG_KERNEL. We can then remove
CONFIG_DETECT_SOFTLOCKUP directly.

So tag CONFIG_LOCKUP_DETECTOR as default y. This is what we want for
most serious kernel debugging anyway.

And also forbid the lockup detector in S390 as it was for the
previous softlockup detector, event though the true reason for that
is not outlined.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
2010-05-16 01:57:27 +02:00
Frederic Weisbecker
89d7ce2a21 lockup_detector: Make BOOTPARAM_SOFTLOCKUP_PANIC depend on LOCKUP_DETECTOR
Panic on softlockups was still depending on the softlockup detector.
But the latter has been merged into the lockup detector now.

Let's update this config dependency.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
2010-05-13 00:27:20 +02:00
Don Zickus
58687acba5 lockup_detector: Combine nmi_watchdog and softlockup detector
The new nmi_watchdog (which uses the perf event subsystem) is very
similar in structure to the softlockup detector.  Using Ingo's
suggestion, I combined the two functionalities into one file:
kernel/watchdog.c.

Now both the nmi_watchdog (or hardlockup detector) and softlockup
detector sit on top of the perf event subsystem, which is run every
60 seconds or so to see if there are any lockups.

To detect hardlockups, cpus not responding to interrupts, I
implemented an hrtimer that runs 5 times for every perf event
overflow event.  If that stops counting on a cpu, then the cpu is
most likely in trouble.

To detect softlockups, tasks not yielding to the scheduler, I used the
previous kthread idea that now gets kicked every time the hrtimer fires.
If the kthread isn't being scheduled neither is anyone else and the
warning is printed to the console.

I tested this on x86_64 and both the softlockup and hardlockup paths
work.

V2:
- cleaned up the Kconfig and softlockup combination
- surrounded hardlockup cases with #ifdef CONFIG_PERF_EVENTS_NMI
- seperated out the softlockup case from perf event subsystem
- re-arranged the enabling/disabling nmi watchdog from proc space
- added cpumasks for hardlockup failure cases
- removed fallback to soft events if no PMU exists for hard events

V3:
- comment cleanups
- drop support for older softlockup code
- per_cpu cleanups
- completely remove software clock base hardlockup detector
- use per_cpu masking on hard/soft lockup detection
- #ifdef cleanups
- rename config option NMI_WATCHDOG to LOCKUP_DETECTOR
- documentation additions

V4:
- documentation fixes
- convert per_cpu to __get_cpu_var
- powerpc compile fixes

V5:
- split apart warn flags for hard and soft lockups

TODO:
- figure out how to make an arch-agnostic clock2cycles call
  (if possible) to feed into perf events as a sample period

[fweisbec: merged conflict patch]

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
LKML-Reference: <1273266711-18706-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-05-12 23:55:33 +02:00
Frederic Weisbecker
a9aa1d02de Merge commit 'v2.6.34-rc7' into perf/nmi
Merge reason: catch up with latest softlockup detector changes.
2010-05-12 23:20:33 +02:00
Paul E. McKenney
55ec936ff4 rcu: enable CPU_STALL_VERBOSE by default
The CPU_STALL_VERBOSE kernel configuration parameter was added to
2.6.34 to identify any preempted/blocked tasks that were preventing
the current grace period from completing when running preemptible
RCU.  As is conventional for new configurations parameters, this
defaulted disabled.  It is now time to enable it by default.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-05-10 11:08:34 -07:00
Lai Jiangshan
2b3fc35f69 rcu: optionally leave lockdep enabled after RCU lockdep splat
There is no need to disable lockdep after an RCU lockdep splat,
so remove the debug_lockdeps_off() from lockdep_rcu_dereference().
To avoid repeated lockdep splats, use a static variable in the inlined
rcu_dereference_check() and rcu_dereference_protected() macros so that
a given instance splats only once, but so that multiple instances can
be detected per boot.

This is controlled by a new config variable CONFIG_PROVE_RCU_REPEATEDLY,
which is disabled by default.  This provides the normal lockdep behavior
by default, but permits people who want to find multiple RCU-lockdep
splats per boot to easily do so.

Requested-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tested-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-05-10 11:08:31 -07:00
H. Peter Anvin
d9c5841e22 Merge branch 'x86/asm' into x86/atomic
Merge reason:
	Conflict between LOCK_PREFIX_HERE and relative alternatives
	pointers

Resolved Conflicts:
	arch/x86/include/asm/alternative.h
	arch/x86/kernel/alternative.c

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-04-29 16:53:17 -07:00
David S. Miller
9343af084c Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Conflicts:
	lib/Kconfig.debug
2010-04-13 00:28:45 -07:00
David S. Miller
8b8d8e2840 sparc64: Support kmemleak.
Only missing thing was an _sdata marker in vmlinux.lds.S

Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-12 23:46:17 -07:00
Michal Simek
47c4c864af microblaze: Enable memory leak detector
Enable DEBUG_KMEMLEAK for microblaze

Signed-off-by: Michal Simek <monstr@monstr.eu>
2010-04-07 07:27:26 +02:00
Mike Frysinger
1d53661d26 blackfin: enable DEBUG_SECTION_MISMATCH
We see only one section mismatch now after thousands of randconfigs, and a
bug has been filed about that one.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-24 16:31:20 -07:00
Ingo Molnar
548b841669 Merge commit 'v2.6.34-rc1' into perf/urgent
Conflicts:
	tools/perf/util/probe-event.c

Merge reason: Pick up -rc1 and resolve the conflict as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-09 17:11:53 +01:00
Simon Kagstrom
0347af4ee3 lkdtm: add debugfs access and loosen KPROBE ties
Add adds a debugfs interface and additional failure modes to LKDTM to
provide similar functionality to the provoke-crash driver submitted here:

  http://lwn.net/Articles/371208/

Crashes can now be induced either through module parameters (as before)
or through the debugfs interface as in provoke-crash.

The patch also provides a new "direct" interface, where KPROBES are not
used, i.e., the crash is invoked directly upon write to the debugfs
file. When built without KPROBES configured, only this mode is available.

Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
Cc: M. Mohan Kumar <mohan@in.ibm.com>
Cc: Americo Wang <xiyou.wangcong@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:32 -08:00
Ingo Molnar
c99c30fead nmi_watchdog: Turn it off by default
It was nice to enable it by default for testing - but before we
push it upstream we want it to be off - so that people can
opt-in gradually.

Cc: Don Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: gorcunov@gmail.com
Cc: aris@redhat.com
LKML-Reference: <1266880143-24943-1-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-28 20:49:00 +01:00
Linus Torvalds
642c4c75a7 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: (44 commits)
  rcu: Fix accelerated GPs for last non-dynticked CPU
  rcu: Make non-RCU_PROVE_LOCKING rcu_read_lock_sched_held() understand boot
  rcu: Fix accelerated grace periods for last non-dynticked CPU
  rcu: Export rcu_scheduler_active
  rcu: Make rcu_read_lock_sched_held() take boot time into account
  rcu: Make lockdep_rcu_dereference() message less alarmist
  sched, cgroups: Fix module export
  rcu: Add RCU_CPU_STALL_VERBOSE to dump detailed per-task information
  rcu: Fix rcutorture mod_timer argument to delay one jiffy
  rcu: Fix deadlock in TREE_PREEMPT_RCU CPU stall detection
  rcu: Convert to raw_spinlocks
  rcu: Stop overflowing signed integers
  rcu: Use canonical URL for Mathieu's dissertation
  rcu: Accelerate grace period if last non-dynticked CPU
  rcu: Fix citation of Mathieu's dissertation
  rcu: Documentation update for CONFIG_PROVE_RCU
  security: Apply lockdep-based checking to rcu_dereference() uses
  idr: Apply lockdep-based diagnostics to rcu_dereference() uses
  radix-tree: Disable RCU lockdep checking in radix tree
  vfs: Abstract rcu_dereference_check for files-fdtable use
  ...
2010-02-28 10:13:16 -08:00
Frederic Weisbecker
dd8b1cf681 perf: Remove pointless breakpoint union
Remove pointless union in the breakpoint field of hw_perf_event.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
2010-02-27 17:10:39 +01:00
Hitoshi Mitake
84c6f88fc8 perf lock: Fix and add misc documentally things
I've forgot to add 'perf lock' line to command-list.txt,
so users of perf could not find perf lock when they type 'perf'.

Fixing command-list.txt requires document
(tools/perf/Documentation/perf-lock.txt).
But perf lock is too much "under construction" to write a
stable document, so this is something like pseudo document for now.

And I wrote description of perf lock at help section of
CONFIG_LOCK_STAT, this will navigate users of lock trace events.

Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
LKML-Reference: <1265267295-8388-1-git-send-email-mitake@dcl.info.waseda.ac.jp>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-02-27 17:05:22 +01:00
Luca Barbieri
86a8938078 lib: Add self-test for atomic64_t
This patch adds self-test on boot code for atomic64_t.

This has been used to test the later changes in this patchset.

Signed-off-by: Luca Barbieri <luca@luca-barbieri.com>
LKML-Reference: <1267005265-27958-4-git-send-email-luca@luca-barbieri.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-25 20:47:12 -08:00
Paul E. McKenney
1ed509a225 rcu: Add RCU_CPU_STALL_VERBOSE to dump detailed per-task information
When RCU detects a grace-period stall, it currently just prints
out the PID of any tasks doing the stalling.  This patch adds
RCU_CPU_STALL_VERBOSE, which enables the more-verbose reporting
from sched_show_task().

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1266887105-1528-21-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 10:35:02 +01:00
Paul E. McKenney
632ee20013 rcu: Introduce lockdep-based checking to RCU read-side primitives
Inspection is proving insufficient to catch all RCU misuses,
which is understandable given that rcu_dereference() might be
protected by any of four different flavors of RCU (RCU, RCU-bh,
RCU-sched, and SRCU), and might also/instead be protected by any
of a number of locking primitives. It is therefore time to
enlist the aid of lockdep.

This set of patches is inspired by earlier work by Peter
Zijlstra and Thomas Gleixner, and takes the following approach:

o	Set up separate lockdep classes for RCU, RCU-bh, and RCU-sched.

o	Set up separate lockdep classes for each instance of SRCU.

o	Create primitives that check for being in an RCU read-side
	critical section.  These return exact answers if lockdep is
	fully enabled, but if unsure, report being in an RCU read-side
	critical section.  (We want to avoid false positives!)
	The primitives are:

	For RCU: rcu_read_lock_held(void)

	For RCU-bh: rcu_read_lock_bh_held(void)

	For RCU-sched: rcu_read_lock_sched_held(void)

	For SRCU: srcu_read_lock_held(struct srcu_struct *sp)

o	Add rcu_dereference_check(), which takes a second argument
	in which one places a boolean expression based on the above
	primitives and/or lockdep_is_held().

o	A new kernel configuration parameter, CONFIG_PROVE_RCU, enables
	rcu_dereference_check().  This depends on CONFIG_PROVE_LOCKING,
	and should be quite helpful during the transition period while
	CONFIG_PROVE_RCU-unaware patches are in flight.

The existing rcu_dereference() primitive does no checking, but
upcoming patches will change that.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1266887105-1528-1-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 09:40:59 +01:00
Don Zickus
c3128fb6ad nmi_watchdog: Use a boolean config flag for compiling
Determines if an arch has setup arch specific perf_events and
nmi_watchdog code.  This should restrict compiles to only those
arches ready.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: gorcunov@gmail.com
Cc: aris@redhat.com
LKML-Reference: <1266013161-31197-1-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-14 09:19:43 +01:00
Ingo Molnar
8e7672cdb4 nmi_watchdog: Only enable on x86 for now
It wont even build on other platforms just yet - so restrict it
to x86 for now.

Cc: Don Zickus <dzickus@redhat.com>
Cc: gorcunov@gmail.com
Cc: aris@redhat.com
Cc: peterz@infradead.org
LKML-Reference: <1265424425-31562-4-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-09 06:11:00 +01:00
Don Zickus
84e478c6f1 nmi_watchdog: Config option to enable new nmi_watchdog
These are the bits that enable the new nmi_watchdog and safely
isolate the old nmi_watchdog.  Only one or the other can run,
not both at the same time.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: gorcunov@gmail.com
Cc: aris@redhat.com
Cc: peterz@infradead.org
LKML-Reference: <1265424425-31562-4-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-08 08:29:03 +01:00
Chris Smith
660e2acad8 sh: kmemleak support.
Enables support for kmemleak on sh.

Signed-off-by: Chris Smith <chris.smith@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-01-27 22:03:11 +09:00
Paul E. McKenney
4c54005ca4 rcu: 1Q2010 update for RCU documentation
Add expedited functions.  Review documentation and update
obsolete verbiage.  Also fix the advice for the RCU CPU-stall
kernel configuration parameter, and document RCU CPU-stall
warnings.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <12635142581866-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16 10:25:22 +01:00
Linus Torvalds
dcc7cd0112 Merge branch 'kmemleak' of git://linux-arm.org/linux-2.6
* 'kmemleak' of git://linux-arm.org/linux-2.6:
  kmemleak: fix kconfig for crc32 build error
  kmemleak: Reduce the false positives by checking for modified objects
  kmemleak: Show the age of an unreferenced object
  kmemleak: Release the object lock before calling put_object()
  kmemleak: Scan the _ftrace_events section in modules
  kmemleak: Simplify the kmemleak_scan_area() function prototype
  kmemleak: Do not use off-slab management with SLAB_NOLEAKTRACE
2009-12-17 16:00:19 -08:00
Alexey Dobriyan
8420e7efa1 Make DEBUG_BUGVERBOSE default to y
It's easy to lose useful DEBUG_BUGVERBOSE by switching EMBEDDED left and right.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:26 -08:00
Linus Torvalds
d71cb81af3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Add debugobjects support
2009-12-10 09:35:44 -08:00
Linus Torvalds
4ef58d4e2a 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: (42 commits)
  tree-wide: fix misspelling of "definition" in comments
  reiserfs: fix misspelling of "journaled"
  doc: Fix a typo in slub.txt.
  inotify: remove superfluous return code check
  hdlc: spelling fix in find_pvc() comment
  doc: fix regulator docs cut-and-pasteism
  mtd: Fix comment in Kconfig
  doc: Fix IRQ chip docs
  tree-wide: fix assorted typos all over the place
  drivers/ata/libata-sff.c: comment spelling fixes
  fix typos/grammos in Documentation/edac.txt
  sysctl: add missing comments
  fs/debugfs/inode.c: fix comment typos
  sgivwfb: Make use of ARRAY_SIZE.
  sky2: fix sky2_link_down copy/paste comment error
  tree-wide: fix typos "couter" -> "counter"
  tree-wide: fix typos "offest" -> "offset"
  fix kerneldoc for set_irq_msi()
  spidev: fix double "of of" in comment
  comment typo fix: sybsystem -> subsystem
  ...
2009-12-09 19:43:33 -08:00
Linus Torvalds
1557d33007 Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6: (43 commits)
  security/tomoyo: Remove now unnecessary handling of security_sysctl.
  security/tomoyo: Add a special case to handle accesses through the internal proc mount.
  sysctl: Drop & in front of every proc_handler.
  sysctl: Remove CTL_NONE and CTL_UNNUMBERED
  sysctl: kill dead ctl_handler definitions.
  sysctl: Remove the last of the generic binary sysctl support
  sysctl net: Remove unused binary sysctl code
  sysctl security/tomoyo: Don't look at ctl_name
  sysctl arm: Remove binary sysctl support
  sysctl x86: Remove dead binary sysctl support
  sysctl sh: Remove dead binary sysctl support
  sysctl powerpc: Remove dead binary sysctl support
  sysctl ia64: Remove dead binary sysctl support
  sysctl s390: Remove dead sysctl binary support
  sysctl frv: Remove dead binary sysctl support
  sysctl mips/lasat: Remove dead binary sysctl support
  sysctl drivers: Remove dead binary sysctl support
  sysctl crypto: Remove dead binary sysctl support
  sysctl security/keys: Remove dead binary sysctl support
  sysctl kernel: Remove binary sysctl logic
  ...
2009-12-08 07:38:50 -08:00
Jiri Kosina
d014d04386 Merge branch 'for-next' into for-linus
Conflicts:

	kernel/irq/chip.c
2009-12-07 18:36:35 +01:00
Linus Torvalds
607781762e 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: (31 commits)
  rcu: Make RCU's CPU-stall detector be default
  rcu: Add expedited grace-period support for preemptible RCU
  rcu: Enable fourth level of TREE_RCU hierarchy
  rcu: Rename "quiet" functions
  rcu: Re-arrange code to reduce #ifdef pain
  rcu: Eliminate unneeded function wrapping
  rcu: Fix grace-period-stall bug on large systems with CPU hotplug
  rcu: Eliminate __rcu_pending() false positives
  rcu: Further cleanups of use of lastcomp
  rcu: Simplify association of forced quiescent states with grace periods
  rcu: Accelerate callback processing on CPUs not detecting GP end
  rcu: Mark init-time-only rcu_bootup_announce() as __init
  rcu: Simplify association of quiescent states with grace periods
  rcu: Rename dynticks_completed to completed_fqs
  rcu: Enable synchronize_sched_expedited() fastpath
  rcu: Remove inline from forward-referenced functions
  rcu: Fix note_new_gpnum() uses of ->gpnum
  rcu: Fix synchronization for rcu_process_gp_end() uses of ->completed counter
  rcu: Prepare for synchronization fixes: clean up for non-NO_HZ handling of ->completed counter
  rcu: Cleanup: balance rcu_irq_enter()/rcu_irq_exit() calls
  ...
2009-12-05 09:52:14 -08:00
André Goddard Rosa
af901ca181 tree-wide: fix assorted typos all over the place
That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-04 15:39:55 +01:00
Paul E. McKenney
8bfb2f8e65 rcu: Make RCU's CPU-stall detector be default
The RCU_CPU_STALL_DETECTOR costs almost nothing and has located
some bugs that might otherwise have been difficult to track
down.  Make it be default for the TREE RCU implementations.

The vmlinux size impact is limited (on 64-bit x86 defconfig):

   text	   data	    bss	    dec	    hex	filename
   8440248	1260076	 995588	10695912	 a334e8	vmlinux.before
   8440774	1260060	 995588	10696422	 a336e6	vmlinux.after

+526 bytes - acceptable default cost.

For RAM starved systems, TINY_RCU does not support CPU-stall detection
and is much smaller, but then again it is a uniprocessor...

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <12597846162906-git-send-email->
[ v2: added image size calculations to the changelog ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-03 11:35:27 +01:00
Thomas Gleixner
dc186ad741 workqueue: Add debugobjects support
Add debugobject support to track the life time of work_structs.

While at it, remove duplicate definition of
INIT_DELAYED_WORK_ON_STACK().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-11-16 01:09:48 +09:00
Eric W. Biederman
83ac201b4f sysctl: Remove dead code from sysctl_check
Now that the sys_sysctl is now a compatibility wrapper around
/proc/sys we can remove much of sysctl_check and reduce it
to a few remaining sanity checks.  This completely decouples
it from the binary sysctl system call.

Little things like ensuring that the sysctl has not already
been registered are all that remain.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-11-11 00:42:53 -08:00
Randy Dunlap
b60e26a2f0 kmemleak: fix kconfig for crc32 build error
kmemleak uses crc32 functions so it needs to select CRC32.
Fixes build error:

kmemleak.c:(.text+0x7ce62): undefined reference to `crc32_le'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-11-06 23:16:04 +00:00
Kumar Gala
01deab98e3 powerpc: Minor cleanup to lib/Kconfig.debug
We don't need an explicit PPC64 in the DEBUG_PREEMPT dependancies as all
PPC platforms now support TRACE_IRQFLAGS_SUPPORT.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-10-27 16:42:42 +11:00
Heiko Carstens
dfcc3e6a8b [S390] Enable kmemleak on s390.
Also increase the maximum possible kmemleak early log entries since
2000 are not sufficient on s390.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-10-06 10:35:06 +02:00
Randy Dunlap
99657c7857 kernel hacking: move STRIP_ASM_SYMS from General
Sam suggested moving STRIP_ASM_SYMS into the Kernel hacking menu
from the General Setup menu.  It makes more sense there.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:42 +02:00
Linus Torvalds
723e9db7a4 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (134 commits)
  powerpc/nvram: Enable use Generic NVRAM driver for different size chips
  powerpc/iseries: Fix oops reading from /proc/iSeries/mf/*/cmdline
  powerpc/ps3: Workaround for flash memory I/O error
  powerpc/booke: Don't set DABR on 64-bit BookE, use DAC1 instead
  powerpc/perf_counters: Reduce stack usage of power_check_constraints
  powerpc: Fix bug where perf_counters breaks oprofile
  powerpc/85xx: Fix SMP compile error and allow NULL for smp_ops
  powerpc/irq: Improve nanodoc
  powerpc: Fix some late PowerMac G5 with PCIe ATI graphics
  powerpc/fsl-booke: Use HW PTE format if CONFIG_PTE_64BIT
  powerpc/book3e: Add missing page sizes
  powerpc/pseries: Fix to handle slb resize across migration
  powerpc/powermac: Thermal control turns system off too eagerly
  powerpc/pci: Merge ppc32 and ppc64 versions of phb_scan()
  powerpc/405ex: support cuImage via included dtb
  powerpc/405ex: provide necessary fixup function to support cuImage
  powerpc/40x: Add support for the ESTeem 195E (PPC405EP) SBC
  powerpc/44x: Add Eiger AMCC (AppliedMicro) PPC460SX evaluation board support.
  powerpc/44x: Update Arches defconfig
  powerpc/44x: Update Arches dts
  ...

Fix up conflicts in drivers/char/agp/uninorth-agp.c
2009-09-15 09:51:09 -07:00
Linus Torvalds
ada3fa1505 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (46 commits)
  powerpc64: convert to dynamic percpu allocator
  sparc64: use embedding percpu first chunk allocator
  percpu: kill lpage first chunk allocator
  x86,percpu: use embedding for 64bit NUMA and page for 32bit NUMA
  percpu: update embedding first chunk allocator to handle sparse units
  percpu: use group information to allocate vmap areas sparsely
  vmalloc: implement pcpu_get_vm_areas()
  vmalloc: separate out insert_vmalloc_vm()
  percpu: add chunk->base_addr
  percpu: add pcpu_unit_offsets[]
  percpu: introduce pcpu_alloc_info and pcpu_group_info
  percpu: move pcpu_lpage_build_unit_map() and pcpul_lpage_dump_cfg() upward
  percpu: add @align to pcpu_fc_alloc_fn_t
  percpu: make @dyn_size mandatory for pcpu_setup_first_chunk()
  percpu: drop @static_size from first chunk allocators
  percpu: generalize first chunk allocator selection
  percpu: build first chunk allocators selectively
  percpu: rename 4k first chunk allocator to page
  percpu: improve boot messages
  percpu: fix pcpu_reclaim() locking
  ...

Fix trivial conflict as by Tejun Heo in kernel/sched.c
2009-09-15 09:39:44 -07:00
Linus Torvalds
eee2775d99 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: (28 commits)
  rcu: Move end of special early-boot RCU operation earlier
  rcu: Changes from reviews: avoid casts, fix/add warnings, improve comments
  rcu: Create rcutree plugins to handle hotplug CPU for multi-level trees
  rcu: Remove lockdep annotations from RCU's _notrace() API members
  rcu: Add #ifdef to suppress __rcu_offline_cpu() warning in !HOTPLUG_CPU builds
  rcu: Add CPU-offline processing for single-node configurations
  rcu: Add "notrace" to RCU function headers used by ftrace
  rcu: Remove CONFIG_PREEMPT_RCU
  rcu: Merge preemptable-RCU functionality into hierarchical RCU
  rcu: Simplify rcu_pending()/rcu_check_callbacks() API
  rcu: Use debugfs_remove_recursive() simplify code.
  rcu: Merge per-RCU-flavor initialization into pre-existing macro
  rcu: Fix online/offline indication for rcudata.csv trace file
  rcu: Consolidate sparse and lockdep declarations in include/linux/rcupdate.h
  rcu: Renamings to increase RCU clarity
  rcu: Move private definitions from include/linux/rcutree.h to kernel/rcutree.h
  rcu: Expunge lingering references to CONFIG_CLASSIC_RCU, optimize on !SMP
  rcu: Delay rcu_barrier() wait until beginning of next CPU-hotunplug operation.
  rcu: Fix typo in rcu_irq_exit() comment header
  rcu: Make rcupreempt_trace.c look at offline CPUs
  ...
2009-09-11 13:20:18 -07:00
David Howells
e0e817392b CRED: Add some configurable debugging [try #6]
Add a config option (CONFIG_DEBUG_CREDENTIALS) to turn on some debug checking
for credential management.  The additional code keeps track of the number of
pointers from task_structs to any given cred struct, and checks to see that
this number never exceeds the usage count of the cred struct (which includes
all references, not just those from task_structs).

Furthermore, if SELinux is enabled, the code also checks that the security
pointer in the cred struct is never seen to be invalid.

This attempts to catch the bug whereby inode_has_perm() faults in an nfsd
kernel thread on seeing cred->security be a NULL pointer (it appears that the
credential struct has been previously released):

	http://www.kerneloops.org/oops.php?number=252883

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-02 21:29:01 +10:00