A frequent mistake appears to be to call task_of() on a
scheduler entity that is not actually a task, which can result
in a wild pointer.
Add a check to catch these mistakes.
Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reflect "active" cpus in the rq->rd->online field, instead of
the online_map.
The motivation is that things that use the root-domain code
(such as cpupri) only care about cpus classified as "active"
anyway. By synchronizing the root-domain state with the active
map, we allow several optimizations.
For instance, we can remove an extra cpumask_and from the
scheduler hotpath by utilizing rq->rd->online (since it is now
a cached version of cpu_active_map & rq->rd->span).
Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Max Krasnyansky <maxk@qualcomm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090730145723.25226.24493.stgit@dev.haskins.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We currently have an explicit "needs_post" vtable method which
returns a stack variable for whether we should later run
post-schedule. This leads to an awkward exchange of the
variable as it bubbles back up out of the context switch. Peter
Zijlstra observed that this information could be stored in the
run-queue itself instead of handled on the stack.
Therefore, we revert to the method of having context_switch
return void, and update an internal rq->post_schedule variable
when we require further processing.
In addition, we fix a race condition where we try to access
current->sched_class without holding the rq->lock. This is
technically racy, as the sched-class could change out from
under us. Instead, we reference the per-rq post_schedule
variable with the runqueue unlocked, but with preemption
disabled to see if we need to reacquire the rq->lock.
Finally, we clean the code up slightly by removing the #ifdef
CONFIG_SMP conditionals from the schedule() call, and implement
some inline helper functions instead.
This patch passes checkpatch, and rt-migrate.
Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090729150422.17691.55590.stgit@dev.haskins.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We need to add the new prio to the cpupri accounting before
removing the old prio. This is because removing the old prio
first will open a race window where the cpu will be removed
from pri_active. In this case the cpu will not be visible for
RT push and pulls. This could cause a RT task to not migrate
appropriately, and create a very large latency.
This bug was found with the use of ftrace sched events and
trace_printk.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090729042526.438281019@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The current method for pushing RT tasks after scheduling only
happens after a context switch. But we found cases where a task
is set up on a run queue to be pushed but the push never
happens because the schedule chooses the same task.
This bug was found with the help of Gregory Haskins and the use
of ftrace (trace_printk). It tooks several days for both of us
analyzing the code and the trace output to find this.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090729042526.205923666@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When cgroup group scheduling is built in, skip some code paths
if we don't have any (but the root) cgroups configured.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit ec4e0e2fe0 ("fix
inconsistency when redistribute per-cpu tg->cfs_rq shares")
broke cgroup smp fairness.
In order to avoid starvation of newly placed tasks, we never
quite set the share of an empty cpu group-task to 0, but
instead we set it as if there's a single NICE-0 task present.
If however we actually set this in cfs_rq[cpu]->shares, that
means the total shares for that group will be slightly inflated
every time we balance, causing the observed unfairness.
Fix this by setting cfs_rq[cpu]->shares to 0 but actually
setting the effective weight of the related se to the inflated
number.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248696557.6987.1615.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Background:
Several race conditions in the scheduler have cropped up
recently, which Steven and I have tracked down using ftrace.
The most recent one turns out to be a race in how the scheduler
determines a suitable migration target for RT tasks, introduced
recently with commit:
commit 68e74568fb
Date: Tue Nov 25 02:35:13 2008 +1030
sched: convert struct cpupri_vec cpumask_var_t.
The original design of cpupri allowed lockless readers to
quickly determine a best-estimate target. Races between the
pri_active bitmap and the vec->mask were handled in the
original code because we would detect and return "0" when this
occured. The design was predicated on the *effective*
atomicity (*) of caching the result of cpus_and() between the
cpus_allowed and the vec->mask.
Commit 68e74568 changed the behavior such that vec->mask is
accessed multiple times. This introduces a subtle race, the
result of which means we can have a result that returns "1",
but with an empty bitmap.
*) yes, we know cpus_and() is not a locked operator across the
entire composite array, but it is implicitly atomic on a
per-word basis which is all the design required to work.
Implementation:
Rather than forgoing the lockless design, or reverting to a
stack-based cpumask_t, we simply check for when the race has
been encountered and continue processing in the event that the
race is hit. This renders the removal race as if the priority
bit had been atomically cleared as well, and allows the
algorithm to execute correctly.
Signed-off-by: Gregory Haskins <ghaskins@novell.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090730145728.25226.92769.stgit@dev.haskins.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The latencytop and sleep accounting code assumes that any
scheduler entity represents a task, this is not so.
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use kernel_text_address() for checking probe address instead of
__kernel_text_address(), because __kernel_text_address() returns true
for init functions even after relaseing those functions.
That will hit a BUG() in text_poke().
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When profile= is used, a large buffer is allocated early at boot. This
can be larger than what the page allocator can provide so it prints a
warning. However, the caller is able to handle the situation so this
patch suppresses the warning.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After commit ec64f51545 ("cgroup: fix
frequent -EBUSY at rmdir"), cgroup's rmdir (especially against memcg)
doesn't return -EBUSY by temporary ref counts. That commit expects all
refs after pre_destroy() is temporary but...it wasn't. Then, rmdir can
wait permanently. This patch tries to fix that and change followings.
- set CGRP_WAIT_ON_RMDIR flag before pre_destroy().
- clear CGRP_WAIT_ON_RMDIR flag when the subsys finds racy case.
if there are sleeping ones, wakes them up.
- rmdir() sleeps only when CGRP_WAIT_ON_RMDIR flag is set.
Tested-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Reported-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Reviewed-by: Paul Menage <menage@google.com>
Acked-by: Balbir Sigh <balbir@linux.vnet.ibm.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The bug was introduced by commit cc31edceee
("cgroups: convert tasks file to use a seq_file with shared pid array").
We cache a pid array for all threads that are opening the same "tasks"
file, but the pids in the array are always from the namespace of the
last process that opened the file, so all other threads will read pids
from that namespace instead of their own namespaces.
To fix it, we maintain a list of pid arrays, which is keyed by pid_ns.
The list will be of length 1 at most time.
Reported-by: Paul Menage <menage@google.com>
Idea-by: Paul Menage <menage@google.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Reviewed-by: Serge Hallyn <serue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Setting
"crashkernel=512M-2G:64M,2G-:128M"
does not work but it turns to work if it has a trailing-whitespace,
like
"crashkernel=512M-2G:64M,2G-:128M ".
It was because of a bug in the parser, running over the cmdline.
This patch adds a check of the termination.
Reported-by: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Tested-by: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a post-2.6.31 regression which was introduced by
2ff05b2b4e ("oom: move oom_adj value from
task_struct to mm_struct").
After moving the oom_adj value from the task struct to the mm_struct, the
oom_adj value was no longer properly inherited by child processes.
Copying over the oom_adj value at fork time fixes that bug.
[kosaki.motohiro@jp.fujitsu.com: test for current->mm before dereferencing it]
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Paul Menage <manage@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 63706172f3 ("kthreads: rework
kthread_stop()") removed the limitation that the thread function mysr
not call do_exit() itself, but forgot to update the comment.
Since that commit it is OK to use kthread_stop() even if kthread can
exit itself.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The check_modstruct_version() needs to look up the symbol "module_layout"
in the kernel, but it does so literally and not by a C identifier. The
trouble is that it does not include a symbol prefix for those ports that
need it (like the Blackfin and H8300 port). So make sure we tack on the
MODULE_SYMBOL_PREFIX define to the front of it.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
migration_init() returns the return value of the hotplug notifier. In
the success case this is NOTIFY_OK which is 1. initcall_debug
evaluates that as an error code because init calls are expected to
return 0 on success.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Every time we cat a trace_stat file, we leak memory allocated by
seq_open().
Also fix memory leak in a failure path in tracing_stat_open().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A67D92B.4060704@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Every time we cat set_graph_function, we leak memory allocated
by seq_open().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A67D907.2010500@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Every time we cat stack_trace, we leak memory allocated by seq_open().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A67D8E8.3020500@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Since genirq: Delegate irq affinity setting to the irq thread
(591d2fb02e) compilation with
CONFIG_SMP=n fails with following error:
/usr/src/linux-2.6/kernel/irq/manage.c:
In function 'irq_thread_check_affinity':
/usr/src/linux-2.6/kernel/irq/manage.c:475:
error: 'struct irq_desc' has no member named 'affinity'
make[4]: *** [kernel/irq/manage.o] Error 1
That commit adds a new function irq_thread_check_affinity() which
uses struct irq_desc.affinity which is only available for CONFIG_SMP=y.
Move that function under #ifdef CONFIG_SMP.
[ tglx@brownpaperbag: compile and boot tested on UP and SMP ]
Signed-off-by: Bruno Premont <bonbons@linux-vserver.org>
LKML-Reference: <20090722222232.2eb3e1c4@neptune.home>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* 'perf-counters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-perf: (31 commits)
perf_counter tools: Give perf top inherit option
perf_counter tools: Fix vmlinux symbol generation breakage
perf_counter: Detect debugfs location
perf_counter: Add tracepoint support to perf list, perf stat
perf symbol: C++ demangling
perf: avoid structure size confusion by using a fixed size
perf_counter: Fix throttle/unthrottle event logging
perf_counter: Improve perf stat and perf record option parsing
perf_counter: PERF_SAMPLE_ID and inherited counters
perf_counter: Plug more stack leaks
perf: Fix stack data leak
perf_counter: Remove unused variables
perf_counter: Make call graph option consistent
perf_counter: Add perf record option to log addresses
perf_counter: Log vfork as a fork event
perf_counter: Synthesize VDSO mmap event
perf_counter: Make sure we dont leak kernel memory to userspace
perf_counter tools: Fix index boundary check
perf_counter: Fix the tracepoint channel to perfcounters
perf_counter, x86: Extend perf_counter Pentium M support
...
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: fix nr_uninterruptible accounting of frozen tasks really
sched: fix load average accounting vs. cpu hotplug
sched: Account for vruntime wrapping
the "reserved" field was not initialized to zero, resulting in 4 bytes
of stack data leaking to userspace....
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now we only print PERF_EVENT_THROTTLE + 1 (ie PERF_EVENT_UNTHROTTLE).
Fix this to print both a throttle and unthrottle event.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090722130546.GE9029@kryten>
Anton noted that for inherited counters the counter-id as provided by
PERF_SAMPLE_ID isn't mappable to the id found through PERF_RECORD_ID
because each inherited counter gets its own id.
His suggestion was to always return the parent counter id, since that
is the primary counter id as exposed. However, these inherited
counters have a unique identifier so that events like
PERF_EVENT_PERIOD and PERF_EVENT_THROTTLE can be specific about which
counter gets modified, which is important when trying to normalize the
sample streams.
This patch removes PERF_EVENT_PERIOD in favour of PERF_SAMPLE_PERIOD,
which is more useful anyway, since changing periods became a lot more
common than initially thought -- rendering PERF_EVENT_PERIOD the less
useful solution (also, PERF_SAMPLE_PERIOD reports the more accurate
value, since it reports the value used to trigger the overflow,
whereas PERF_EVENT_PERIOD simply reports the requested period changed,
which might only take effect on the next cycle).
This still leaves us PERF_EVENT_THROTTLE to consider, but since that
_should_ be a rare occurrence, and linking it to a primary id is the
most useful bit to diagnose the problem, we introduce a
PERF_SAMPLE_STREAM_ID, for those few cases where the full
reconstruction is important.
[Does change the ABI a little, but I see no other way out]
Suggested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248095846.15751.8781.camel@twins>
the "reserved" field was not initialized to zero, resulting in 4 bytes
of stack data leaking to userspace....
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
commit ca109491f (hrtimer: removing all ur callback modes) moved all
hrtimer callbacks into hard interrupt context when high resolution
timers are active. That breaks code which relied on the assumption
that the callback happens in softirq context.
Provide a generic infrastructure which combines tasklets and hrtimers
together to provide an in-softirq hrtimer experience.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: torvalds@linux-foundation.org
Cc: kaber@trash.net
Cc: David Miller <davem@davemloft.net>
LKML-Reference: <1248265724.27058.1366.camel@twins>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
irq_set_thread_affinity() calls set_cpus_allowed_ptr() which might
sleep, but irq_set_thread_affinity() is called with desc->lock held
and can be called from hard interrupt context as well. The code has
another bug as it does not hold a ref on the task struct as required
by set_cpus_allowed_ptr().
Just set the IRQTF_AFFINITY bit in action->thread_flags. The next time
the thread runs it migrates itself. Solves all of the above problems
nicely.
Add kerneldoc to irq_set_thread_affinity() while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Writing a zero length string to sys/.../current_clocksource will cause
a NULL pointer dereference if the clock events system is in one shot
(highres or nohz) mode.
Pointed-out-by: Dan Carpenter <error27@gmail.com>
LKML-Reference: <alpine.DEB.2.00.0907191545580.12306@bicker>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
timer->expires may be uninitialized, so check timer_pending() before
touching timer->expires to pacify kmemcheck.
Signed-off-by: Pavel Roskin <proski@gnu.org>
LKML-Reference: <20090718204602.5191.360.stgit@mj.roinet.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
might_sleep() is called late-ish in cond_resched(), after the
need_resched()/preempt enabled/system running tests are
checked.
It's better to check the sleeps while atomic earlier and not
depend on some environment datas that reduce the chances to
detect a problem.
Also define cond_resched_*() helpers as macros, so that the
FILE/LINE reported in the sleeping while atomic warning
displays the real origin and not sched.h
Changes in v2:
- Call __might_sleep() directly instead of might_sleep() which
may call cond_resched()
- Turn cond_resched() into a macro so that the file:line
couple reported refers to the caller of cond_resched() and
not __cond_resched() itself.
Changes in v3:
- Also propagate this __might_sleep() pull up to
cond_resched_lock() and cond_resched_softirq()
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1247725694-6082-6-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a preempt count base offset to compare against the current
preempt level count. It prepares to pull up the might_sleep
check from cond_resched() to cond_resched_lock() and
cond_resched_bh().
For these two helpers, we need to respectively ensure that once
we'll unlock the given spinlock / reenable local softirqs, we
will reach a sleepable state.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
[ Move and rename preempt_count_equals() ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1247725694-6082-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cover the off case for __might_sleep(), so that we avoid
#ifdefs in files that make use of it. Especially, this prepares
for the __might_sleep() pull up on cond_resched().
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1247725694-6082-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove the outdated comment from __cond_resched() related to
the now removed Big Kernel Semaphore.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1247725694-6082-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The schedule() function is a loop that reschedules the current
task while the TIF_NEED_RESCHED flag is set:
void schedule(void)
{
need_resched:
/* schedule code */
if (need_resched())
goto need_resched;
}
And cond_resched() repeat this loop:
do {
add_preempt_count(PREEMPT_ACTIVE);
schedule();
sub_preempt_count(PREEMPT_ACTIVE);
} while(need_resched());
This loop is needless because schedule() already did the check
and nothing can set TIF_NEED_RESCHED between schedule() exit
and the loop check in need_resched().
Then remove this needless loop.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1247725694-6082-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
commit e3c8ca8336 (sched: do not count frozen tasks toward load) broke
the nr_uninterruptible accounting on freeze/thaw. On freeze the task
is excluded from accounting with a check for (task->flags &
PF_FROZEN), but that flag is cleared before the task is thawed. So
while we prevent that the task with state TASK_UNINTERRUPTIBLE
is accounted to nr_uninterruptible on freeze we decrement
nr_uninterruptible on thaw.
Use a separate flag which is handled by the freezing task itself. Set
it before calling the scheduler with TASK_UNINTERRUPTIBLE state and
clear it after we return from frozen state.
Cc: <stable@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The new load average code clears rq->calc_load_active on
CPU_ONLINE. That's wrong as the new onlined CPU might have got a
scheduler tick already and accounted the delta to the stale value of
the time we offlined the CPU.
Clear the value when we cleanup the dead CPU instead.
Also move the update of the calc_load_update time for the newly online
CPU to CPU_UP_PREPARE to avoid that the CPU plays catch up with the
stale update time value.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When profile= is used, a large buffer is allocated early at
boot. This can be larger than what the page allocator can
provide so it prints a warning. However, the caller is able to
handle the situation so this patch suppresses the warning.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Linux Memory Management List <linux-mm@kvack.org>
Cc: Heinz Diehl <htd@fancy-poultry.org>
Cc: David Miller <davem@davemloft.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1247656992-19846-3-git-send-email-mel@csn.ul.ie>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Right now we don't output vfork events. Even though we should
always see an exec after a vfork, we may get perfcounter
samples between the vfork and exec. These samples can lead to
some confusion when parsing perfcounter data.
To keep things consistent we should always log a fork event. It
will result in a little more log data, but is less confusing to
trace parsing tools.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090716104817.589309391@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There are a few places we are leaking tiny amounts of kernel
memory to userspace. This happens when writing out strings
because we always align the end to 64 bits.
To avoid this we should always use an appropriately sized
temporary buffer and ensure it is zeroed.
Since d_path assembles the string from the end of the buffer
backwards, we need to add 64 bits after the buffer to allow for
alignment.
We also need to copy arch_vma_name to the temporary buffer,
because if we use it directly we may end up copying to
userspace a number of bytes after the end of the string
constant.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090716104817.273972048@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
