PM / devfreq: Fix simple_ondemand crashing

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: Blechd0se <alex.christ@hotmail.de>
PM: devfreq: Fix show available freqs

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: Blechd0se <alex.christ@hotmail.de>
PM: devfreq: Always reflect a change of polling interval

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: Blechd0se <alex.christ@hotmail.de>
PM: devfreq: Add sysfs nodes for devfreq governors

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: Blechd0se <alex.christ@hotmail.de>
devfreq: fix merge derp.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: Blechd0se <alex.christ@hotmail.de>
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>
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>
writeback: fix occasional slow sync(1)

In case when system contains no dirty pages, wakeup_flusher_threads() will
submit WB_SYNC_NONE writeback for 0 pages so wb_writeback() exits
immediately without doing anything, even though there are dirty inodes in
the system.  Thus sync(1) will write all the dirty inodes from a
WB_SYNC_ALL writeback pass which is slow.

Fix the problem by using get_nr_dirty_pages() in wakeup_flusher_threads()
instead of calculating number of dirty pages manually.  That function also
takes number of dirty inodes into account.

Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Paul Taysom <taysom@chromium.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
block: disable io_stat
drivers: mmc: disable CRC.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
Signed-off-by: Seongmin Park <r_data@naver.com>
block: recursive merge requests

In a workload, thread 1 accesses a, a+2, ..., thread 2 accesses a+1, a+3,....
When the requests are flushed to queue, a and a+1 are merged to (a, a+1), a+2
and a+3 too to (a+2, a+3), but (a, a+1) and (a+2, a+3) aren't merged.

If we do recursive merge for such interleave access, some workloads throughput
get improvement. A recent worload I'm checking on is swap, below change
boostes the throughput around 5% ~ 10%.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
fs/dcache.c: Fix the too small buffer for dname

temp[64] is used for internal temporary buffer in dynamic_dname().
This is for dname. But It's too small. dname's size may be > 64.
In that case, it returns as -ENAMETOOLONG. So Increase the buffer size
to 256 for avoiding this issue.

The following was caused by the small buffer.
WARNING: at /kernel/mm/page_alloc.c:2470 __alloc_pages_nodemask+0x24c/0x938()
CPU: 2 PID: 505 Comm: android.bg Not tainted 3.10.0-g2f73780-00003-g2ff41d9-dirty #13
[<c010ba3c>] (unwind_backtrace+0x0/0x11c) from [<c0109cac>] (show_stack+0x10/0x14)
[<c0109cac>] (show_stack+0x10/0x14) from [<c01939a0>] (warn_slowpath_common+0x48/0x68)
[<c01939a0>] (warn_slowpath_common+0x48/0x68) from [<c0193a7c>] (warn_slowpath_null+0x18/0x20)
[<c0193a7c>] (warn_slowpath_null+0x18/0x20) from [<c0222454>] (__alloc_pages_nodemask+0x24c/0x938)
[<c0222454>] (__alloc_pages_nodemask+0x24c/0x938) from [<c0222b50>] (__get_free_pages+0x10/0x24)
[<c0222b50>] (__get_free_pages+0x10/0x24) from [<c024faf8>] (kmalloc_order_trace+0x24/0xf0)
[<c024faf8>] (kmalloc_order_trace+0x24/0xf0) from [<c024fe20>] (__kmalloc+0x30/0x244)
[<c024fe20>] (__kmalloc+0x30/0x244) from [<c02723c8>] (seq_read+0x270/0x464)
[<c02723c8>] (seq_read+0x270/0x464) from [<c0256a18>] (vfs_read+0xa4/0x134)
[<c0256a18>] (vfs_read+0xa4/0x134) from [<c0256de8>] (SyS_read+0x38/0x68)
[<c0256de8>] (SyS_read+0x38/0x68) from [<c0106140>] (ret_fast_syscall+0x0/0x30)

Change-Id: I74f5217ba3c4be73e91f33f900f1f0c26810cc05
Signed-off-by: Devin Kim <dojip.kim@lge.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
ext4: optimize test_root()

The test_root() function could potentially loop forever due to
overflow issues.  So rewrite test_root() to avoid this issue; as a
bonus, it is 38% faster when benchmarked via a test loop:

int main(int argc, char **argv)
{
	int  i;

	for (i = 0; i < 1 << 24; i++) {
		if (test_root(i, 7))
			printf("%d\n", i);
	}
}

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
wlan: Do not check for mcbc flag to resume.

On a host resume driver sends resume request to the firmware
to terminate the requisite offload functionality (PNO) as well
as disables few offload requisite explicitly, and this is
done only when MCBC filter flag is set. That said ,it would
lead to failed behavior if disable and resume request are
not issued to the firmware.
Address this by sending the resume request and disabling
offloads irrespective of the MCBC filters state.

CRs-fixed: 543098
Change-Id: I0a2192c50ba6e20d7cd7aaa98fe4cb26d050c943
(cherry picked from commit 3d15fbfab6729058614c4de4d05d7af246d23217)
Signed-off-by: Paul Reioux <reioux@gmail.com>
wlan: reload WLAN driver if cannot recover from RX low resource

If WLAN host driver could not recover Out of RX buffer problem,
Trigger re-load host driver to recover from dead end

Change-Id: I04895f56892cc0b25fcee341829eb7eb91ab1553
CRs-fixed: 500022
Signed-off-by: Paul Reioux <reioux@gmail.com>
wlan: adding check for ts_info.up.

'params' is user controlled, and 'ts_info.up' could be defined to be
greater than maximum sme_QosWmmUpType enum, resulting in hddWmmUpToAcMap
being indexed out of bounds.
Validated 0 < ts_info.up < SME_QOS_WMM_UP_MAX.

Change-Id: Ia1966db2a6c8ce8d3a9422f0dd9d91a59573c783
CRs-Fixed: 567234
Signed-off-by: Paul Reioux <reioux@gmail.com>
writeback: I believe these defines were calculated with HZ=1000 in mind. Yes, really  . . .
So lets hard set them to 200 like they are meant to be, not 20 lol
Signed-off-by: renderbroken <zkennedy87@gmail.com>
sched: LOAD_FREQ (4*HZ+61) avoids loadavg Moire

These values are applicable for 100 HZ device.
Check http://ripke.com/loadavg/moire for more details.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
tcp: network speed tweak

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm_vidc_enc:Fix Entropysel