Input: Propagate hardware event timestamp to evdev.

Convey hardware timestamp associated with the current event packet.
The use of these event codes by hardware drivers is optional.
Used to reduce jitter and improve velocity tracking in ABS_MT devices.

Change-Id: I89f3a958944f6a2979964ee372e61bad448061b6
Signed-off-by: Sasha Levitskiy <sanek@google.com>
sched: Reset rq->next_interval before going idle

next_balance, the point in jiffy time scale when a cpu will next load
balance, could have been calculated when the cpu was busy. A busy cpu
will apply its sched domain's busy_factor (usually > 1) in computing
next_balance for that sched domain, which causes the (busy) cpu to load
balance less frequently in its sched domains. However when the same cpu
is going idle, its next_balance needs to be reset without consideration
of busy_factor. Failure to do so would not trigger nohz idle balancer on
that cpu for unnecessarily long time (introducing additional scheduling
latencies for tasks). Fix bug in scheduler which aims to reset
next_balance before a cpu goes idle (as per existing comment) but is
clearly not doing so.

Change-Id: I7e027a51686528c4092d770c7d33c874d38f5df4
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
sched: Fix SCHED_HRTICK bug leading to late preemption of tasks

SCHED_HRTICK feature is useful to preempt SCHED_FAIR tasks on-the-dot
(just when they would have exceeded their ideal_runtime). It makes use
of a a per-cpu hrtimer resource and hence alarming that hrtimer should
be based on total SCHED_FAIR tasks a cpu has across its various cfs_rqs,
rather than being based on number of tasks in a particular cfs_rq (as
implemented currently). As a result, with current code, its possible for
a running task (which is the sole task in its cfs_rq) to be preempted
much after its ideal_runtime has elapsed, resulting in increased latency
for tasks in other cfs_rq on same cpu.

Fix this by alarming sched hrtimer based on total number of SCHED_FAIR
tasks a CPU has across its various cfs_rqs.

Change-Id: I1f23680a64872f8ce0f451ac4bcae28e8967918f
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
sched: fix reference to wrong cfs_rq

Commit 7db16c8c (sched: Fix SCHED_HRTICK bug leading to late preemption
of tasks) introduced a bug in sched_slice() calculation by using wrong
cfs_rq for tasks. rq->cfs was incorrectly used as task's cfs_rq, rather
than the correct one to which they belonged.

Fix the bug by using correct cfs_rq for tasks.

Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
sched: Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()s

try_to_wake_up_local() should only be invoked to wake up another
task in the same runqueue and BUG_ON()s are used to enforce the
rule. Missing try_to_wake_up_local() can stall workqueue
execution but such stalls are likely to be finite either by
another work item being queued or the one blocked getting
unblocked.  There's no reason to trigger BUG while holding rq
lock crashing the whole system.

Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()s.

Change-Id: I75fdaaf4dcaefcf3893e0404d98c8aa91f89934d
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130318192234.GD3042@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Git-commit: 383efcd00053ec40023010ce5034bd702e7ab373
CRs-Fixed: 519942
Signed-off-by: Steve Muckle <smuckle@codeaurora.org>
sched: change WARN_ON_ONCE to WARN_ON in try_to_wake_up_local()

The WARN_ON_ONCE() calls at the beginning of try_to_wake_up_local()
were recently converted from BUG_ON() calls. If these hit it indicates
something is wrong and that may contribute to other system instability.
To eliminate the risk of an instance of one of these errors going
un-noticed because there was an earlier instance that occured long ago,
change to WARN_ON(). If there ever is a flood of these there are bigger
problems.

Change-Id: I392832e2b6ec24b3569b001b1af9ecd4ed6828e7
Signed-off-by: Steve Muckle <smuckle@codeaurora.org>
cpufreq: Resolve CPUFREQ_NOTIFY issue

When the cpufreq_stat receives the frequency policy notification,
it checks if the frequency table and stats table are present for the cpu.
If both are present, it returns with -EBUSY error to the notification.
Due to this, none of the other registered modules receive this
notification.

If the stat table and sysfs nodes are already created, return 0 instead
of returning EBUSY error.

Change-Id: I1fd4a46e6a65edfc6253c4271288f10912ae2ad7
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
fs/sync: Make sync() satisfy many requests with one invocation

Dave Jones reported RCU stalls, overly long hrtimer interrupts, and
amazingly long NMI handlers from a trinity-induced workload involving
lots of concurrent sync() calls (https://lkml.org/lkml/2013/7/23/369).
There are any number of things that one might do to make sync() behave
better under high levels of contention, but it is also the case that
multiple concurrent sync() system calls can be satisfied by a single
sys_sync() invocation.

Given that this situation is reminiscent of rcu_barrier(), this commit
applies the rcu_barrier() approach to sys_sync().  This approach uses
a global mutex and a sequence counter.  The mutex is held across the
sync() operation, which eliminates contention between concurrent sync()
operations.  The counter is incremented at the beginning and end of
each sync() operation, so that it is odd while a sync() operation is in
progress and even otherwise, just like sequence locks.

The code that used to be in sys_sync() is now in do_sync(), and sys_sync()
now handles the concurrency.  The sys_sync() function first takes a
snapshot of the counter, then acquires the mutex, and then takes another
snapshot of the counter.  If the values of the two snapshots indicate that
a full do_sync() executed during the mutex acquisition, the sys_sync()
function releases the mutex and returns ("Our work is done!").  Otherwise,
sys_sync() increments the counter, invokes do_sync(), and increments
the counter again.

This approach allows a single call to do_sync() to satisfy an arbitrarily
large number of sync() system calls, which should eliminate issues due
to large numbers of concurrent invocations of the sync() system call.

Changes since v1 (https://lkml.org/lkml/2013/7/24/683):

o	Add a pair of memory barriers to keep the increments from
	bleeding into the do_sync() code.  (The failure probability
	is insanely low, but when you have several hundred million
	devices running Linux, you can expect several hundred instances
	of one-in-a-million failures.)

o	Actually CC some people who have experience in this area.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Curt Wohlgemuth <curtw@google.com>
Cc: Jens Axboe <jaxboe@fusionio.com>
Cc: linux-fsdevel@vger.kernel.org

Signed-off-by: Paul Reioux <reioux@gmail.com>
Staging: android: binder: Fix memory leak on thread/process exit

If a thread or process exited while a reply, one-way transaction or
death notification was pending, the struct holding the pending work
was leaked.

CRs-Fixed: 477612
Change-Id: I8b7a4f77689731a47c9e2f2fffefcac95c412e00
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Git-commit: 675d66b0ed5fd170d6a44cf8dbb3fa56a5347bdb
Git-repo: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
msm_fb: display: fix iommu page fault when iommu buffer freed

There has possibility that pipe commit come very close to next vsync.
This may cause two consecutive pipe_commits happen within same vsync
period which cause iommu page fault when previous iommu buffer is
freed since mdp stil fetching it. Set ION_IOMMU_UNMAP_DELAYED flag
at ion_map_iommu() to add delay un mapping iommu buffer to fix this problem.
Otherwise four buffer mechanism is needed to avoid this problem..
Also ion_unmap_iommu() may take long time to free an ion buffer. Move
mdp4_overlay_iommu_unmap_freelist(mixer) called after stage_commit()
to increase chance to have pipe_commit (up to stage_commit) is completed
within same vsync period
This patch also fix an potential race condition at wait_for_completion
between show_event thread and wait4vsync thread.

Change-Id: I673b0e368bbcd3120bc26569fe7a7bb82931daaa
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
(cherry picked from commit ada63be0fd32e729e4b91aeeea2a5cfe0830148c)
(cherry picked from commit 799796f15e0b78ffe47975db1cf7f3791cb98129)
msm: move printk out of spin lock low_water_lock

cpu3 stuck in printk more time in spin lock low_water_lock cause cpu0
get spin lock fail and system crashed.

CRs-Fixed: 521570
Change-Id: I75356a4b4171ae2888ce6cce792f569b5ca8cdcf
Signed-off-by: Tingting Yang <tingting@codeaurora.org>