OK, so commit:
1d8fe7dc80 ("locking/mutexes: Unlock the mutex without the wait_lock")
generates this boot warning when CONFIG_DEBUG_MUTEXES=y:
WARNING: CPU: 0 PID: 139 at /usr/src/linux-2.6/kernel/locking/mutex-debug.c:82 debug_mutex_unlock+0x155/0x180() DEBUG_LOCKS_WARN_ON(lock->owner != current)
And that makes sense, because as soon as we release the lock a
new owner can come in...
One would think that !__mutex_slowpath_needs_to_unlock()
implementations suffer the same, but for DEBUG we fall back to
mutex-null.h which has an unconditional 1 for that.
The mutex debug code requires the mutex to be unlocked after
doing the debug checks, otherwise it can find inconsistent
state.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: jason.low2@hp.com
Link: http://lkml.kernel.org/r/20140312122442.GB27965@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I decided to run my tests on linux-next, and my wakeup_rt tracer was
broken. After running a bisect, I found that the problem commit was:
linux-next commit c365c292d0
"sched: Consider pi boosting in setscheduler()"
And the reason the wake_rt tracer test was failing, was because it had
no RT task to trace. I first noticed this when running with
sched_switch event and saw that my RT task still had normal SCHED_OTHER
priority. Looking at the problem commit, I found:
- p->normal_prio = normal_prio(p);
- p->prio = rt_mutex_getprio(p);
With no
+ p->normal_prio = normal_prio(p);
+ p->prio = rt_mutex_getprio(p);
Reading what the commit is suppose to do, I realize that the p->prio
can't be set if the task is boosted with a higher prio, but the
p->normal_prio still needs to be set regardless, otherwise, when the
task is deboosted, it wont get the new priority.
The p->prio has to be set before "check_class_changed()" is called,
otherwise the class wont be changed.
Also added fix to newprio to include a check for deadline policy that
was missing. This change was suggested by Juri Lelli.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: SebastianAndrzej Siewior <bigeasy@linutronix.de>
Cc: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140306120438.638bfe94@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull audit namespace fixes from Eric Biederman:
"Starting with 3.14-rc1 the audit code is faulty (think oopses and
races) with respect to how it computes the network namespace of which
socket to reply to, and I happened to notice by chance when reading
through the code.
My testing and the automated build bots don't find any problems with
these fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
audit: Update kdoc for audit_send_reply and audit_list_rules_send
audit: Send replies in the proper network namespace.
audit: Use struct net not pid_t to remember the network namespce to reply in
The mcs_spinlock code is not meant (or suitable) as a generic locking
primitive, therefore take it away from the normal includes and place
it in kernel/locking/.
This way the locking primitives implemented there can use it as part
of their implementation but we do not risk it getting used
inapropriately.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-byirmpamgr7h25m5kyavwpzx@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1) Single cpu machine case.
When rq has only RT tasks, but no one of them can be picked
because of throttling, we enter in endless loop.
pick_next_task_{dl,rt} return NULL.
In pick_next_task_fair() we permanently go to retry
if (rq->nr_running != rq->cfs.h_nr_running)
return RETRY_TASK;
(rq->nr_running is not being decremented when rt_rq becomes
throttled).
No chances to unthrottle any rt_rq or to wake fair here,
because of rq is locked permanently and interrupts are
disabled.
2) In case of SMP this can cause a hang too. Although we unlock
rq in idle_balance(), interrupts are still disabled.
The solution is to check for available tasks in DL and RT
classes instead of checking for sum.
Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394098321.19290.11.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The problems:
1) We check for rt_nr_running before call of put_prev_task().
If previous task is RT, its rt_rq may become throttled
and dequeued after this call.
In case of p is from rt->rq this just causes picking a task
from throttled queue, but in case of its rt_rq is child
we are guaranteed catch BUG_ON.
2) The same with deadline class. The only difference we operate
on only dl_rq.
This patch fixes all the above problems and it adds a small skip in the
DL update like we've already done for RT class:
if (unlikely((s64)delta_exec <= 0))
return;
This will optimize sequential update_curr_dl() calls a little.
Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Link: http://lkml.kernel.org/r/1393946746.3643.3.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Double ! or !! are normally required to get 0 or 1 out of a expression. A
comparision always returns 0 or 1 and hence there is no need to apply double !
over it again.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
GFP_THISNODE is for callers that implement their own clever fallback to
remote nodes. It restricts the allocation to the specified node and
does not invoke reclaim, assuming that the caller will take care of it
when the fallback fails, e.g. through a subsequent allocation request
without GFP_THISNODE set.
However, many current GFP_THISNODE users only want the node exclusive
aspect of the flag, without actually implementing their own fallback or
triggering reclaim if necessary. This results in things like page
migration failing prematurely even when there is easily reclaimable
memory available, unless kswapd happens to be running already or a
concurrent allocation attempt triggers the necessary reclaim.
Convert all callsites that don't implement their own fallback strategy
to __GFP_THISNODE. This restricts the allocation a single node too, but
at the same time allows the allocator to enter the slowpath, wake
kswapd, and invoke direct reclaim if necessary, to make the allocation
happen when memory is full.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kbuild test robot reported:
> tree: git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git for-next
> head: 6f285b19d0
> commit: 6f285b19d0 [2/2] audit: Send replies in the proper network namespace.
> reproduce: make htmldocs
>
> >> Warning(kernel/audit.c:575): No description found for parameter 'request_skb'
> >> Warning(kernel/audit.c:575): Excess function parameter 'portid' description in 'audit_send_reply'
> >> Warning(kernel/auditfilter.c:1074): No description found for parameter 'request_skb'
> >> Warning(kernel/auditfilter.c:1074): Excess function parameter 'portid' description in 'audit_list_rules_s
Which was caused by my failure to update the kdoc annotations when I
updated the functions. Fix that small oversight now.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull cgroup fixes from Tejun Heo:
"Two cpuset locking fixes from Li. Both tagged for -stable"
* 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: fix a race condition in __cpuset_node_allowed_softwall()
cpuset: fix a locking issue in cpuset_migrate_mm()
Pull tracing fix from Steven Rostedt:
"In the past, I've had lots of reports about trace events not working.
Developers would say they put a trace_printk() before and after the
trace event but when they enable it (and the trace event said it was
enabled) they would see the trace_printks but not the trace event.
I was not able to reproduce this, but that's because I wasn't looking
at the right location. Recently, another bug came up that showed the
issue.
If your kernel supports signed modules but allows for non-signed
modules to be loaded, then when one is, the kernel will silently set
the MODULE_FORCED taint on the module. Although, this taint happens
without the need for insmod --force or anything of the kind, it labels
the module with that taint anyway.
If this tainted module has tracepoints, the tracepoints will be
ignored because of the MODULE_FORCED taint. But no error message will
be displayed. Worse yet, the event infrastructure will still be
created letting users enable the trace event represented by the
tracepoint, although that event will never actually be enabled. This
is because the tracepoint infrastructure allows for non-existing
tracepoints to be enabled for new modules to arrive and have their
tracepoints set.
Although there are several things wrong with the above, this change
only addresses the creation of the trace event files for tracepoints
that are not created when a module is loaded and is tainted. This
change will print an error message about the module being tainted and
not the trace events will not be created, and it does not create the
trace event infrastructure"
* tag 'trace-fixes-v3.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Do not add event files for modules that fail tracepoints
Pull irq fixes from Thomas Gleixner:
- a bugfix for a long standing waitqueue race
- a trivial fix for a missing include
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Include missing header file in irqdomain.c
genirq: Remove racy waitqueue_active check
In order to allow the COMPAT_SYSCALL_DEFINE macro generate code that
performs proper zero and sign extension convert all 64 bit parameters
to their corresponding 32 bit compat counterparts.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
In order to allow the COMPAT_SYSCALL_DEFINE macro generate code that
performs proper zero and sign extension convert all 64 bit parameters
to their corresponding 32 bit compat counterparts.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Convert all compat system call functions where all parameter types
have a size of four or less than four bytes, or are pointer types
to COMPAT_SYSCALL_DEFINE.
The implicit casts within COMPAT_SYSCALL_DEFINE will perform proper
zero and sign extension to 64 bit of all parameters if needed.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
trace_block_rq_complete does not take into account that request can
be partially completed, so we can get the following incorrect output
of blkparser:
C R 232 + 240 [0]
C R 240 + 232 [0]
C R 248 + 224 [0]
C R 256 + 216 [0]
but should be:
C R 232 + 8 [0]
C R 240 + 8 [0]
C R 248 + 8 [0]
C R 256 + 8 [0]
Also, the whole output summary statistics of completed requests and
final throughput will be incorrect.
This patch takes into account real completion size of the request and
fixes wrong completion accounting.
Signed-off-by: Roman Pen <r.peniaev@gmail.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: linux-kernel@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
If a module fails to add its tracepoints due to module tainting, do not
create the module event infrastructure in the debugfs directory. As the events
will not work and worse yet, they will silently fail, making the user wonder
why the events they enable do not display anything.
Having a warning on module load and the events not visible to the users
will make the cause of the problem much clearer.
Link: http://lkml.kernel.org/r/20140227154923.265882695@goodmis.org
Fixes: 6d723736e4 "tracing/events: add support for modules to TRACE_EVENT"
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable@vger.kernel.org # 2.6.31+
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull scheduler fixes from Ingo Molnar:
"Misc fixes, most of them SCHED_DEADLINE fallout"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/deadline: Prevent rt_time growth to infinity
sched/deadline: Switch CPU's presence test order
sched/deadline: Cleanup RT leftovers from {inc/dec}_dl_migration
sched: Fix double normalization of vruntime
Include appropriate header file kernel/time/timekeeping_internal.h in
kernel/time/timekeeping_debug.c because it has prototype declaration of
function defined in kernel/time/timekeeping_debug.c.
This eliminates the following warning in
kernel/time/timekeeping_debug.c:
kernel/time/timekeeping_debug.c:68:6: warning: no previous prototype for ‘tk_debug_account_sleep_time’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Pull perf fixes from Ingo Molnar:
"Misc fixes, most of them on the tooling side"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf tools: Fix strict alias issue for find_first_bit
perf tools: fix BFD detection on opensuse
perf: Fix hotplug splat
perf/x86: Fix event scheduling
perf symbols: Destroy unused symsrcs
perf annotate: Check availability of annotate when processing samples