sync: don't block the flusher thread waiting on IO

When sync does it's WB_SYNC_ALL writeback, it issues data Io and
then immediately waits for IO completion. This is done in the
context of the flusher thread, and hence completely ties up the
flusher thread for the backing device until all the dirty inodes
have been synced. On filesystems that are dirtying inodes constantly
and quickly, this means the flusher thread can be tied up for
minutes per sync call and hence badly affect system level write IO
performance as the page cache cannot be cleaned quickly.

We already have a wait loop for IO completion for sync(2), so cut
this out of the flusher thread and delegate it to wait_sb_inodes().
Hence we can do rapid IO submission, and then wait for it all to
complete.

Effect of sync on fsmark before the patch:

FSUse%        Count         Size    Files/sec     App Overhead
.....
     0       640000         4096      35154.6          1026984
     0       720000         4096      36740.3          1023844
     0       800000         4096      36184.6           916599
     0       880000         4096       1282.7          1054367
     0       960000         4096       3951.3           918773
     0      1040000         4096      40646.2           996448
     0      1120000         4096      43610.1           895647
     0      1200000         4096      40333.1           921048

And a single sync pass took:

  real    0m52.407s
  user    0m0.000s
  sys     0m0.090s

After the patch, there is no impact on fsmark results, and each
individual sync(2) operation run concurrently with the same fsmark
workload takes roughly 7s:

  real    0m6.930s
  user    0m0.000s
  sys     0m0.039s

IOWs, sync is 7-8x faster on a busy filesystem and does not have an
adverse impact on ongoing async data write operations.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
msm: mdp: Disable early suspend only for the MDP driver

Early suspend is deprecated in the framework but disabling it
completely can affect other subsystems. Disabling only for the
MDP driver.

Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
msm: mdp: Disable early suspend locally

undefing at the header level could mess with other components.

Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
msm: display: command mode panel release fence

For command mode panel, release fence should be signaled after the buffer is
sent to the panel.  For performance consideration, allow one more commit to be
queued.  Keep the second kick off as short as enough.

Change-Id: I19af075ebf480d3e81b46b1cd2ef21a2893f143e
Signed-off-by: Ken Zhang <kenz@codeaurora.org>
Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
Signed-off-by: Iliyan Malchev <malchev@google.com>
msm: mdp: Change msmfb kworker to kthread

This worker can be a longer running task depending on the number
of frames queued, hence change it to a thread.

Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
Change-Id: Iebf7e95d0486ac43aa6a12d70442936600c0249a
msm: mdp: Update sync pt. behaviour

Add a retire fence and clean up the existing release fence
implementation

Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
Change-Id: Iecf7e95d0786ac43aa6a12d70442936600c0249a
msm: display: Set dsi_panel_off flag in panel off function

* Because command mode panels are capable of queuing multiple commits
  while panel is turning off, the dsi_panel_off flag must be
  manipulated in the actual panel off function (panel_disable) to avoid
  a race where the commit thread re-enables a panel that has already
  been turned off.

Change-Id: I1e678013fbf7b147464eeaed76a31e82129f8868
msm: vidc: free the recon buffers in cleanup function

- The recon buffers were not released when video recording
  was killed abruptly leading to memory leak.

- Fix provided to release the recon buffers when media
  server killed abruptly.

Change-Id: I48ac1a592719446b7e4bf87bbd707d09351d1e61
Signed-off-by: srikarri <sridur@codeaurora.org>