mm: optimize Kernel Samepage Merging(KSM)

Signed-off-by: Dan Trifan <jimsth@gmail.com>
defconfig: enable Kernel Samepage Merging(KSM)

Signed-off-by: Dan Trifan <jimsth@gmail.com>
governors/menu.c: Reduce nr_iowait_cpu to 2 for Idle

Signed-off-by: Dan Trifan <jimsth@gmail.com>
i2c: use usleep_range to wait instead of msleep

according to the docs msleep(1) means wait up 20ms. i2c bus probably
doesn't need to wait that long. Potential performance boost.

Signed-off-by: Dan Trifan <jimsth@gmail.com>
sched: don't call task_group() many times in set_task_rq()

It improves perfomance, especially if autogroup enabled.

The size of set_task_rq() was 0x180 and now it is 0xa0.

Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
mutex: dynamically disable mutex spinning at high load
Date	Thu, 4 Apr 2013 10:54:18 -0400

The Linux mutex code has a MUTEX_SPIN_ON_OWNER configuration
option that was enabled by default in major distributions like Red
Hat. Allowing threads waiting on mutex to spin while the mutex owner
is running will theoretically reduce latency on the acquisition of
mutex at the expense of energy efficiency as the spinning threads
are doing no useful work.

This is not a problem on a lightly loaded system where the CPU may
be idle anyway. On a highly loaded system, the spinning tasks may be
blocking other tasks from running even if they have higher priority
because the spinning was done with preemption disabled.

This patch will disable mutex spinning if the current load is high
enough. The load is considered high if there are 2 or more active tasks
waiting to run on the current CPU. If there is only one task waiting,
it will check the average load at the past minute (calc_load_tasks).
If it is more than double the number of active CPUs, the load is
considered high too.  This is a rather simple metric that does not
incur that much additional overhead.

The AIM7 benchmarks were run on 3.7.10 derived kernels to show the
performance changes with this patch on a 8-socket 80-core system
with hyperthreading off.  The table below shows the mean % change
in performance over a range of users for some AIM7 workloads with
just the less atomic operation patch (patch 1) vs the less atomic
operation patch plus this one (patches 1+3).

+--------------+-----------------+-----------------+-----------------+
|   Workload   | mean % change   | mean % change   | mean % change   |
|              | 10-100 users    | 200-1000 users  | 1100-2000 users |
+--------------+-----------------+-----------------+-----------------+
| alltests     |      0.0%       |     -0.1%       |    +5.0%        |
| five_sec     |     +1.5%       |     +1.3%       |    +1.3%        |
| fserver      |     +1.5%       |    +25.4%       |    +9.6%        |
| high_systime |     +0.1%       |      0.0%       |    +0.8%        |
| new_fserver  |     +0.2%       |    +11.9%       |   +14.1%        |
| shared       |     -1.2%       |     +0.3%       |    +1.8%        |
| short        |     +6.4%       |     +2.5%       |    +3.0%        |
+--------------+-----------------+-----------------+-----------------+
It can be seen that this patch provides some big performance
improvement for the fserver and new_fserver workloads while is still
generally positive for the other AIM7 workloads.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Reviewed-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
modified for tuna kernel from LKML

Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
power: decrease the amount of time the device waits after entering lower power state - Thanks Franco

Signed-off-by: Dan Trifan <jimsth@gmail.com>
ARM: 7178/1: fault.c: Port OOM changes into do_page_fault

Commit d065bd810b6deb67d4897a14bfe21f8eb526ba99
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e0525d393d48a7d59f870b3bc061a30ccdb
(x86,mm: make pagefault killable)

The above commits introduced changes into the x86 pagefault handler
for making the page fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial
during OOM killer invocation.

Port these changes to ARM.

Without these changes, my ARM board encounters many hang and livelock
scenarios.
After applying this patch, OOM feature performance improves according to
my testing.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dan Trifan <jimsth@gmail.com>

Conflicts:

	arch/arm/mm/fault.c
modified for Tuna kernel from Mainline by faux123

Signed-off-by: Dan Trifan <jimsth@gmail.com>
readahead: fault retry breaks mmap file read random detection

.fault now can retry.  The retry can break state machine of .fault.  In
filemap_fault, if page is miss, ra->mmap_miss is increased.  In the second
try, since the page is in page cache now, ra->mmap_miss is decreased.  And
these are done in one fault, so we can't detect random mmap file access.

Add a new flag to indicate .fault is tried once.  In the second try, skip
ra->mmap_miss decreasing.  The filemap_fault state machine is ok with it.

I only tested x86, didn't test other archs, but looks the change for other
archs is obvious, but who knows :)

Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Wu Fengguang <fengguang.wu@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
modified for Tuna kernel from Linux Mainline by faux123

Signed-off-by: Dan Trifan <jimsth@gmail.com>
arch:arm:omap4:board-tuna-display.c: purple tint fix.

Fix 80-100% purple tint at low/minimum brightness.

Credits go to mpokwsths.

Signed-off-by: Dan Trifan <jimsth@gmail.com>
Linux v3.0.97

This is the 3.0.97 stable release.

Signed-off-by: Dan Trifan <jimsth@gmail.com>
Linux v3.0.98

This is the 3.0.98 stable release.

Signed-off-by: Dan Trifan <jimsth@gmail.com>
Tuna: add option to reclaim ~55 MB of reserved RAM (BIGMEM)

Reclaim 50M of RAM from HEAP_TILER and 5M from the OMAP framebuffer.
If we reclam max 50 MB from HEAP_TILER, 1080p mode is still working.

Credits to mpokwsths for the idea,  boype for making it a more organized and BigBrother1984 for the safe reclaim value.

Signed-off-by: Dan Trifan <jimsth@gmail.com>
defconfig: enable TUNA_BIGMEM

Signed-off-by: Dan Trifan <jimsth@gmail.com>
Input: Send events one packet at a time

On heavy event loads, such as a multitouch driver, the irqsoff latency
can be as high as 250 us.  By accumulating a frame worth of data
before passing it on, the latency can be dramatically reduced.  As a
side effect, the special EV_SYN handling can be removed, since the
frame is now atomic.

This patch adds the events() handler callback and uses it if it
exists. The latency is improved by 50 us even without the callback.

Change-Id: Iebd9b1868ae6300a922a45b6d104e7c2b38e4cf5
Cc: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Ping Cheng <pingc@wacom.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

Input: Improve the events-per-packet estimate

The events-per-packet estimate has so far been used by MT devices
only. This patch adjusts the packet buffer size to also accomodate the
KEY and MSC events.  Keyboards normally send one or two keys at a
time. MT devices normally send a number of button keys along with the
MT information.  The buffer size chosen here covers those cases, and
matches the default buffer size in evdev. Since the input estimate is
now preferred, remove the special input-mt estimate.

Reviewed-and-tested-by: Ping Cheng <pingc@wacom.com>
Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
ARM: 7017/1: Use generic BUG() handler

ARM uses its own BUG() handler which makes its output slightly different
from other archtectures.

One of the problems is that the ARM implementation doesn't report the function
with the BUG() in it, but always reports the PC being in __bug(). The generic
implementation doesn't have this problem.

Currently we get something like:

kernel BUG at fs/proc/breakme.c:35!
Unable to handle kernel NULL pointer dereference at virtual address 00000000
...
PC is at __bug+0x20/0x2c

With this patch it displays:

kernel BUG at fs/proc/breakme.c:35!
Internal error: Oops - undefined instruction: 0 [#1] PREEMPT SMP
...
PC is at write_breakme+0xd0/0x1b4

This implementation uses an undefined instruction to implement BUG, and sets up
a bug table containing the relevant information. Many versions of gcc do not
support %c properly for ARM (inserting a # when they shouldn't) so we work
around this using distasteful macro magic.

v1: Initial version to replace existing ARM BUG() implementation with something
more similar to other architectures.

v2: Add Thumb support, remove backtrace whitespace output changes. Change to
use macros instead of requiring the asm %d flag to work (thanks to
Dave Martin <dave.martin@linaro.org>)

v3: Remove old BUG() implementation in favor of this one.
Remove the Backtrace: message (will submit this separately).
Use ARM_EXIT_KEEP() so that some architectures can dump exit text at link time
thanks to Stephen Boyd <sboyd@codeaurora.org> (although since we always
define GENERIC_BUG this might be academic.)
Rebase to linux-2.6.git master.

v4: Allow BUGS in modules (these were not reported correctly in v3)
(thanks to Stephen Boyd <sboyd@codeaurora.org> for suggesting that.)
Remove __bug() as this is no longer needed.

v5: Add %progbits as the section flags.

Change-Id: I9f588a06ddd739138fddfa6a5bf67079796e68eb
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
defconfig: enable GENERIC_BUG

Signed-off-by: Dan Trifan <jimsth@gmail.com>
Linux v3.0.99

This is the 3.0.99 stable release.

Signed-off-by: Dan Trifan <jimsth@gmail.com>
ARM: 7168/1: use cache type functions for arch_get_unmapped_area

There are already cache type decoding functions, so use those instead
of custom decode code which only works for ARMv6.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
OMAP4: PM: Fix missed PRCM MPU interrupt events

OMAP PRCM detects events with EDGE sensitivity. Edge sensitivity
requires to clear the interrupt event status bit before acknowledging
the source event.
If the source event is cleared (1) before reseting the interrupt event
status bit (2), then a subsequent source event (i.e edge) between (1)
and (2) would be missed. Then, all the source events would be kept
"masked" until the source event is cleared again.

The bug seen here is that upon two consecutive PRCM interrupt events
from the IO daisy chain source event, the second event is missed if it
occurs before the PRCM interrupt event status is cleared.
Since the IO daisy chain source event has not been acknowledged, the
subseqent events from this source are missed too.

This patch fix the PRCM interrupt handler by acknowledging the interrupt
event status bit before clearing the source event.

Change-Id: I8c43a93c3b6c7c654ddaa262b7c1c3e7385da158
Signed-off-by: Patrick Combes <p-combes@ti.com>
Signed-off-by: Cedric Poignet <c-poignet@ti.com>
Signed-off-by: Dan Trifan <jimsth@gmail.com>