msm: memutils: memcpy, memmove, copy_page optimization
Preload farther to take advantage of the memory bus, and assume
64-byte cache lines.  Unroll some pairs of ldm/stm as well, for
unexplainable reasons.

Future enhancements should include,

- #define for how far to preload, possibly defined separately for
  memcpy, copy_*_user
- Tuning for misaligned buffers
- Tuning for memmove
- Tuning for small buffers
- Understanding mechanism behind ldm/stm unroll causing some gains
  in copy_to_user

BASELINE (msm8960pro):
======================================================================
memcpy 1000MB at 5MB       : took 808850 usec, bandwidth 1236.236 MB/s
copy_to_user 1000MB at 5MB : took 810071 usec, bandwidth 1234.234 MB/s
copy_from_user 1000MB at 5M: took 942926 usec, bandwidth 1060.060 MB/s
memmove 1000GB at 5MB      : took 848588 usec, bandwidth 1178.178 MB/s
copy_to_user 1000GB at 4kB : took 847916 usec, bandwidth 1179.179 MB/s
copy_from_user 1000GB at 4k: took 935113 usec, bandwidth 1069.069 MB/s
copy_page 1000GB at 4kB    : took 779459 usec, bandwidth 1282.282 MB/s

THIS PATCH:
======================================================================
memcpy 1000MB at 5MB       : took 346223 usec, bandwidth 2888.888 MB/s
copy_to_user 1000MB at 5MB : took 348084 usec, bandwidth 2872.872 MB/s
copy_from_user 1000MB at 5M: took 348176 usec, bandwidth 2872.872 MB/s
memmove 1000GB at 5MB      : took 348267 usec, bandwidth 2871.871 MB/s
copy_to_user 1000GB at 4kB : took 377018 usec, bandwidth 2652.652 MB/s
copy_from_user 1000GB at 4k: took 371829 usec, bandwidth 2689.689 MB/s
copy_page 1000GB at 4kB    : took 383763 usec, bandwidth 2605.605 MB/s

Change-Id: I843fe77192d61ce35a81e75d76fc09f0a472e98a
Signed-off-by: Chris Fries <C.Fries@motorola.com>

Conflicts:
	arch/arm/lib/Makefile
	arch/arm/mach-msm/Kconfig
msm: memutils: memcpy, memmove optimization

1. To fit 8x26 64-bytes cache line size, we change preload steps as 64Bytes.
2. According to tune result, change preload distance as 5 cache lines.
3. According to tune result, re-arrange the ld/str order as back-to-back
   for copy_from_user.

The markable improvement:
	memcpy : 5%
	copy_to_user : 9%
	copy_from_user : 13%
	memmove : 37%

Raw data is as below:

BASELINE:
	memcpy 1000MB at 5MB       : took 1547098 usec, bandwidth 646.646 MB/s
	copy_to_user 1000MB at 5MB : took 1704308 usec, bandwidth 586.586 MB/s
	copy_from_user 1000MB at 5M: took 1777090 usec, bandwidth 562.562 MB/s
	memmove 1000GB at 5MB      : took 1066205 usec, bandwidth 937.937 MB/s
	copy_to_user 1000GB at 4kB : took 1774866 usec, bandwidth 563.563 MB/s
	copy_from_user 1000GB at 4k: took 1797654 usec, bandwidth 556.556 MB/s
	copy_page 1000GB at 4kB    : took 1644606 usec, bandwidth 608.608 MB/s
	memmove 1000GB at 4kB      : took 1236227 usec, bandwidth 808.808 MB/s

THIS PATCH:
	memcpy 1000MB at 5MB       : took 1475835 usec, bandwidth 677.677 MB/s
	copy_to_user 1000MB at 5MB : took 1559060 usec, bandwidth 641.641 MB/s
	copy_from_user 1000MB at 5M: took 1561603 usec, bandwidth 640.640 MB/s
	memmove 1000GB at 5MB      : took 861664 usec, bandwidth 1160.160 MB/s
	copy_to_user 1000GB at 4kB : took 1673501 usec, bandwidth 597.597 MB/s
	copy_from_user 1000GB at 4k: took 1674006 usec, bandwidth 597.597 MB/s
	copy_page 1000GB at 4kB    : took 1691358 usec, bandwidth 591.591 MB/s
	memmove 1000GB at 4kB      : took 882985 usec, bandwidth 1132.132 MB/s

Change-Id: I83bec3b7a9dd9cd88890eaa7ec423363e230a651
Signed-off-by: Hong-Mei Li <a21834@motorola.com>
Reviewed-on: http://gerrit.pcs.mot.com/550383
SLT-Approved: Slta Waiver <sltawvr@motorola.com>
Tested-by: Jira Key <jirakey@motorola.com>
Reviewed-by: Klocwork kwcheck <klocwork-kwcheck@sourceforge.mot.com>
Reviewed-by: Check Patch <CHEKPACH@motorola.com>
Reviewed-by: Yi-Wei Zhao <gbjc64@motorola.com>
Submit-Approved: Jira Key <jirakey@motorola.com>
[LINARO] workqueues: Introduce new flag WQ_POWER_EFFICIENT for power oriented workqueues

Adapted for 3.4 from lsk-v3.10

Workqueues can be performance or power-oriented. Currently, most workqueues are
bound to the CPU they were created on. This gives good performance (due to cache
effects) at the cost of potentially waking up otherwise idle cores (Idle from
scheduler's perspective. Which may or may not be physically idle) just to
process some work. To save power, we can allow the work to be rescheduled on a
core that is already awake.

Workqueues created with the WQ_UNBOUND flag will allow some power savings.
However, we don't change the default behaviour of the system.  To enable
power-saving behaviour, a new config option CONFIG_WQ_POWER_EFFICIENT needs to
be turned on. This option can also be overridden by the
workqueue.power_efficient boot parameter.

tj: Updated config description and comments.  Renamed
    CONFIG_WQ_POWER_EFFICIENT to CONFIG_WQ_POWER_EFFICIENT_DEFAULT.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
(cherry picked from commit cee22a1)
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
[LINARO] workqueue: Add system wide power_efficient workqueues
Adapted for 3.4 from lsk-v3.10

This patch adds system wide workqueues aligned towards power saving. This is
done by allocating them with WQ_UNBOUND flag if 'wq_power_efficient' is set to
'true'.

tj: updated comments a bit.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
(cherry picked from commit 0668106)
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
[LINARO] block: queue work on power efficient wq
Adapted for 3.4 from lsk-v3.10

Block layer uses workqueues for multiple purposes. There is no real dependency
of scheduling these on the cpu which scheduled them.

On a idle system, it is observed that and idle cpu wakes up many times just to
service this work. It would be better if we can schedule it on a cpu which the
scheduler believes to be the most appropriate one.

This patch replaces normal workqueues with power efficient versions.

Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
(cherry picked from commit 695588f)
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
PHYLIB: queue work on system_power_efficient_wq

Adapted for 3.4 from lsk-v3.10

Phylib uses workqueues for multiple purposes. There is no real dependency of
scheduling these on the cpu which scheduled them.

On a idle system, it is observed that and idle cpu wakes up many times just to
service this work. It would be better if we can schedule it on a cpu which the
scheduler believes to be the most appropriate one.

This patch replaces system_wq with system_power_efficient_wq for PHYLIB.

Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Tejun Heo <tj@kernel.org>
(cherry picked from commit bbb47bdeae756f04b896b55b51f230f3eb21f207)
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
ASoC: pcm: Use the power efficient workqueue for delayed powerdown

Adapted for 3.4 from lsk-v3.10

There is no need to use a normal per-CPU workqueue for delayed power downs
as they're not timing or performance critical and waking up a core for them
would defeat some of the point.

Signed-off-by: Mark Brown <broonie@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
(cherry picked from commit d4e1a73acd4e894f8332f2093bceaef585cfab67)
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
regulator: core: Use the power efficient workqueue for delayed powerdown

There is no need to use a normal per-CPU workqueue for delayed power downs
as they're not timing or performance critical and waking up a core for them
would defeat some of the point.

Signed-off-by: Mark Brown <broonie@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Liam Girdwood <liam.r.girdwood@intel.com>
(cherry picked from commit 070260f07c7daec311f2466eb9d1df475d5a46f8)

Signed-off-by: Luis Cruz <ljc2491@gmail.com>
ASoC: jack: Use power efficient workqueue

The accessory detect debounce work is not performance sensitive so let
the scheduler run it wherever is most efficient rather than in a per CPU
workqueue by using the system power efficient workqueue.

Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
(cherry picked from commit e6058aaadcd473e5827720dc143af56aabbeecc7)

Signed-off-by: Luis Cruz <ljc2491@gmail.com>
update configs

Conflicts:
	arch/arm/configs/cyanogenmod_e970_defconfig
	arch/arm/configs/cyanogenmod_e975_defconfig
net/neighbour: queue work on power efficient wq

Workqueue used in neighbour layer have no real dependency of scheduling these on
the cpu which scheduled them.

On a idle system, it is observed that an idle cpu wakes up many times just to
service this work. It would be better if we can schedule it on a cpu which the
scheduler believes to be the most appropriate one.

This patch replaces normal workqueues with power efficient versions. This
doesn't change existing behavior of code unless CONFIG_WQ_POWER_EFFICIENT is
enabled.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Revert "sched: disable gentle fair sleepers"

This reverts commit 26a79bf0ae1c75bd5aaf35664cf8fdadecf0552c.
Revert "ARM: 7587/1: implement optimized percpu variable access"

This reverts commit 7c1f2d286076292c58407bf65e1e518ea82cf941.
SELinux: remove needless sel_div function

I'm not really sure what the idea behind the sel_div function is, but it's
useless.  Since a and b are both unsigned, it's impossible for a % b < 0.
That means that part of the function never does anything.  Thus it's just a
normal /.  Just do that instead.  I don't even understand what that operation
was supposed to mean in the signed case however....

If it was signed:
sel_div(-2, 4) == ((-2 / 4) - ((-2 % 4) < 0))
		  ((0)      - ((-2)     < 0))
		  ((0)      - (1))
		  (-1)

What actually happens:
sel_div(-2, 4) == ((18446744073709551614 / 4) - ((18446744073709551614 % 4) < 0))
		  ((4611686018427387903)      - ((2 < 0))
		  (4611686018427387903        - 0)
		  ((unsigned int)4611686018427387903)
		  (4294967295)

Neither makes a whole ton of sense to me.  So I'm getting rid of the
function entirely.

Signed-off-by: Eric Paris <eparis@redhat.com>
SELinux: possible NULL deref in context_struct_to_string

It's possible that the caller passed a NULL for scontext.  However if this
is a defered mapping we might still attempt to call *scontext=kstrdup().
This is bad.  Instead just return the len.

Signed-off-by: Eric Paris <eparis@redhat.com>
SELinux: delay initialization of audit data in selinux_inode_permission

We pay a rather large overhead initializing the common_audit_data.
Since we only need this information if we actually emit an audit
message there is little need to set it up in the hot path.  This patch
splits the functionality of avc_has_perm() into avc_has_perm_noaudit(),
avc_audit_required() and slow_avc_audit().  But we take care of setting
up to audit between required() and the actual audit call.  Thus saving
measurable time in a hot path.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Eric Paris <eparis@redhat.com>

Conflicts:
	security/selinux/avc.c
SELinux: remove inode_has_perm_noadp

Both callers could better be using file_has_perm() to get better audit
results.

Signed-off-by: Eric Paris <eparis@redhat.com>
SELinux: move common_audit_data to a noinline slow path function

selinux_inode_has_perm is a hot path.  Instead of declaring the
common_audit_data on the stack move it to a noinline function only used in
the rare case we need to send an audit message.

Signed-off-by: Eric Paris <eparis@redhat.com>
SELinux: remove auditdeny from selinux_audit_data

It's just takin' up space.

Signed-off-by: Eric Paris <eparis@redhat.com>
selinuxfs snprintf() misuses

a) %d does _not_ produce a page worth of output
b) snprintf() doesn't return negatives - it used to in old glibc, but
that's the kernel...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>