ARM: 7565/1: sched: stop sched_clock() during suspend

The scheduler imposes a requirement to sched_clock()
which is to stop the clock during suspend, if we don't
do that any RT thread will be rescheduled in the future
which might cause any sort of problems.

This became an issue on OMAP when we converted omap-i2c.c
to use threaded IRQs, it turned out that depending on how
much time we spent on suspend, the I2C IRQ thread would
end up being rescheduled so far in the future that I2C
transfers would timeout and, because omap_hsmmc depends
on an I2C-connected device to detect if an MMC card is
inserted in the slot, our rootfs would just vanish.

arch/arm/kernel/sched_clock.c already had an optional
implementation (sched_clock_needs_suspend()) which would
handle scheduler's requirement properly, what this patch
does is simply to make that implementation non-optional.

Note that this has the side-effect that printk timings
won't reflect the actual time spent on suspend so other
methods to measure that will have to be used.

This has been tested with beagleboard XM (OMAP3630) and
pandaboard rev A3 (OMAP4430). Suspend to RAM is now working
after this patch.

Thanks to Kevin Hilman for helping out with debugging.

Acked-by: Kevin Hilman <khilman@ti.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
CRs-Fixed: 497236
Git-commit: 6a4dae5e138a32b45ca5218cc2b81802f9d378c3
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
(cherry picked from commit 6e15c7004b98c005e150eda28922d7028492a195)

Change-Id: I8b0eb22cf5381a2d9e7a40e7b9e781e6c4f90391
Signed-off-by: Sridhar Nelloru <nellos@codeaurora.org>

Conflicts:
	arch/arm/kernel/sched_clock.c
sched: Make sure to not re-read variables after validation

We could re-read rq->rt_avg after we validated it was smaller than
total, invalidating the check and resulting in an unintended negative.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/1337688268.9698.29.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CRs-Fixed: 497236
Git-commit: b654f7de41b0e3903ee2b51d3b8db77fe52ce728
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
(cherry picked from commit fef154fa32c5d8ef992f11e11919495979970678)

Change-Id: Ieac7a10d9f4ceb701660f8055efd7a0ed5d939ca
Signed-off-by: Sridhar Nelloru <nellos@codeaurora.org>
ARM: 7643/1: sched: correct update_sched_clock()

If we want load epoch_cyc and epoch_ns atomically,
we should update epoch_cyc_copy first of all.
This notify reader that updating is in progress.

If we update epoch_cyc first like as current implementation,
there is subtle error case.
Look at the below example.

<Initial Condition>
cyc = 9
ns = 900
cyc_copy = 9

== CASE 1 ==
<CPU A = reader>           <CPU B = updater>
                           write cyc = 10
read cyc = 10
read ns = 900
                           write ns = 1000
                           write cyc_copy = 10
read cyc_copy = 10

output = (10, 900)

== CASE 2 ==
<CPU A = reader>           <CPU B = updater>
read cyc = 9
                           write cyc = 10
                           write ns = 1000
read ns = 1000
read cyc_copy = 9
                           write cyc_copy = 10
output = (9, 1000)

If atomic read is ensured, output should be (9, 900) or (10, 1000).
But, output in example case are not.

So, change updating sequence in order to correct this problem.

Cc: <stable@vger.kernel.org>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
CRs-Fixed: 497236
Git-commit: 7c4e9ced424be4d36df6a3e3825763e97ee97607
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
(cherry picked from commit eb00ac1da3608c73fb97b276ffd118c1c81d668f)

Change-Id: I7fbcee822fc4d95e54ceb81da1d71d2b46296c0c
Signed-off-by: Sridhar Nelloru <nellos@codeaurora.org>
ARM: 7643/1: sched: correct update_sched_clock()

If we want load epoch_cyc and epoch_ns atomically,
we should update epoch_cyc_copy first of all.
This notify reader that updating is in progress.

If we update epoch_cyc first like as current implementation,
there is subtle error case.
Look at the below example.

<Initial Condition>
cyc = 9
ns = 900
cyc_copy = 9

== CASE 1 ==
<CPU A = reader>           <CPU B = updater>
                           write cyc = 10
read cyc = 10
read ns = 900
                           write ns = 1000
                           write cyc_copy = 10
read cyc_copy = 10

output = (10, 900)

== CASE 2 ==
<CPU A = reader>           <CPU B = updater>
read cyc = 9
                           write cyc = 10
                           write ns = 1000
read ns = 1000
read cyc_copy = 9
                           write cyc_copy = 10
output = (9, 1000)

If atomic read is ensured, output should be (9, 900) or (10, 1000).
But, output in example case are not.

So, change updating sequence in order to correct this problem.

Cc: <stable@vger.kernel.org>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
CRs-Fixed: 497236
Git-commit: 7c4e9ced424be4d36df6a3e3825763e97ee97607
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
(cherry picked from commit eb00ac1da3608c73fb97b276ffd118c1c81d668f)

Change-Id: I7fbcee822fc4d95e54ceb81da1d71d2b46296c0c
Signed-off-by: Sridhar Nelloru <nellos@codeaurora.org>
sched: Make sure to not re-read variables after validation

We could re-read rq->rt_avg after we validated it was smaller than
total, invalidating the check and resulting in an unintended negative.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/1337688268.9698.29.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CRs-Fixed: 497236
Git-commit: b654f7de41b0e3903ee2b51d3b8db77fe52ce728
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
(cherry picked from commit fef154fa32c5d8ef992f11e11919495979970678)

Change-Id: Ieac7a10d9f4ceb701660f8055efd7a0ed5d939ca
Signed-off-by: Sridhar Nelloru <nellos@codeaurora.org>

Conflicts:
	kernel/sched/fair.c
sched: re-calculate a cpu's next_balance point upon sched domain changes

Commit 55ddeb0f (sched: Reset rq->next_interval before going idle) reset
a cpu's rq->next_balance when pulled_task = 0, which will be true when
the cpu failed to pull any task, causing it go idle. However that patch
relied on next_balance being calculated as a result of traversing cpu's
sched domain hierarchy.

A cpu that is the only online cpu will however not be attached to any
sched domain hierarchy. When such a cpu calls into idle_balance(), we
will end up initializing next_balance to be 1sec away! Such a CPU will
defer load balance check for another 1sec, even though we may bring up
more cpus in the meantime requiring it to check for load imbalance more
frequently. This could then lead to increased scheduling latency for
some tasks.

This patch results in a cpu's next_balance being re-calculated when its
attaching to a new sched domain hierarchy.  This should let cpus call
load balance checks at the right time we expect them to!

Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
(cherry picked from commit 91b609bdd91513c37c410ffef0204f8a0578e4f8)

Change-Id: Ib457f1a357aad26e49837a01311b73e22e0cc26f
Signed-off-by: Sridhar Nelloru <nellos@codeaurora.org>
msm: kgsl: Process all idle checks

Rather than ignore some categories of idle events,
bin the events with small timelines and process all
events with the GPU DCVS algorithm.

CRs-Fixed: 427559
Signed-off-by: Lucille Sylvester <lsylvest@codeaurora.org>
Change-Id: I1a5e8d8af6020a08cf95a9daa934e825bc5f2854
Signed-off-by: Paul Reioux <reioux@gmail.com>

Conflicts:
	drivers/gpu/msm/kgsl_pwrscale_trustzone.c
msm: kgsl: Bump up the GPU frequency for long batch processing

Compute workloads run without kernel interaction for long periods
of time.  If one is identified early, increase the frequency to
finish it as fast as possible, rather than waiting for the standard
algorithm to do so.

Change-Id: I213ccabfae5e1000cdc34bc1d92bdc3bad86383d
CRs-Fixed: 441847
Signed-off-by: Lucille Sylvester <lsylvest@codeaurora.org>
Signed-off-by: Paul Reioux <reioux@gmail.com>

Conflicts:
	drivers/gpu/msm/kgsl_pwrscale_trustzone.c
zram swap: LMK and memcontrol update from Samsung SGS 4 update 2 source drop

Signed-off-by: Paul Reioux <reioux@gmail.com>

Conflicts:
	drivers/staging/android/lowmemorykiller.c
	mm/memcontrol.c