cpufreq: Retain only online cpus in managed_policy->cpus

cpufreq's handling of cpu online event can incorrectly initialize
managed_policy->cpus to include offline cpus. This causes cpufreq
governors to include offline cpus in their idle time computation, which
causes frequency to shoot up beyond normal levels (on systems where 2 or
more cpus need to be synchronized wrt frequency change).

This frequency shootup was not seen prior to commit 21111be8 which
changed idle time accounting for offline cpus. Prior to commit 21111be8,
idle time statistics for offline cpus would include their offline time
as well. Post commit 21111be8, offline time is not included in a cpu's
idle time statistics.

As a result, ondemand (or other cpufreq) governors would see unchanged
idle time for offline cpus, causing them to interpret those (offline)
cpus as 100% busy, which is wrong.

This patch fixes the issue by modifying cpufreq's hotplug handling to
retain only online cpus in managed_policy->cpus field. cpufreq governors
would then skip such offline cpus from idle time calculations.

Change-Id: Id2eba8c0ec3367609369b2e42a4e1386ff2e7ab5
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
cpufreq: intellidemand: Fix optimal_freq logic on ramp down

When ondemand governor decides to ramp down the frequency, the missing
check for frequency being lower than optimal_freq was causing frequency
to be ramped down to optimal_freq even if the frequency decided by ondemand
governor was higher.

Change-Id: I00f9ae4c61ccda4039f3338dee2c29b8cb790be4
Signed-off-by: Veena Sambasivan <veenas@codeaurora.org>
Signed-off-by: Paul Reioux <reioux@gmail.com>
cpufreq: Resolve CPUFREQ_NOTIFY issue

When the cpufreq_stat receives the frequency policy notification,
it checks if the frequency table and stats table are present for the cpu.
If both are present, it returns with -EBUSY error to the notification.
Due to this, none of the other registered modules receive this
notification.

If the stat table and sysfs nodes are already created, return 0 instead
of returning EBUSY error.

Change-Id: I1fd4a46e6a65edfc6253c4271288f10912ae2ad7
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
msm: audio: qdsp6v2: Add size safety check to ACDB driver

Check that the size sent by userspace is not larger
then the internal amount allowed. This protects
against overflowing the stack due to an invalid size.

Change-Id: I8230fdb00a7b57d398929e8ab0eb6587476f3db1
CRs-fixed: 470222
Signed-off-by: Ben Romberger <bromberg@codeaurora.org>
msm: rq_stats: Fix missing initalization of cur_freq

Initialize cur_freq variable of each online cpu to the current
running cpu clock frequency. This avoids zeroing out the load
calculations until the first notification of the change in CPU
frequency comes in after CPUFREQ governors are intialized.

Also when a non boot cpu is up, update its cur_freq variable.

(cherry picked from commit 1633a48b16614e6b85c047a19ec93867c2ced3b3)

Change-Id: I950686deff02e2339eefae7d09392dda2174a545
CRs-fixed: 446017
Signed-off-by: Venkat Devarasetty <vdevaras@codeaurora.org>

Conflicts:
	arch/arm/mach-msm/msm_rq_stats.c
msm:rq_stats: Add hotplug disable attribute

Register for suspend and resume notifications from kernel. This should
be done as part of core_initcall so as to receive notification as close
as possible to the actual event. Add hotplug_disable attribute to
rq-stats node. Set/clear this attribute based on the suspend/resume events.

CRS-fixed: 452456
Change-Id: I76fee349b57f47df40785e9c2503e2e1cc6e064e
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
msm:rq_stats: Fix hotplug attribute during the suspend failure

If the system suspend fails, the hotplug_disable attribute remains
set. This prevents any change to core status from mpdecision. Reset
the value of this attribute if the module receives PM_POST_RESTORE
notification.

Change-Id: I22fd639134adbeb8f8f96603e285151480f537ec
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
msm:rq_stats: Register for Cpufreq policy notification

Currently the load of the system is calculated using the max
frequency that is read during startup(It does not get updated
when the policy changes). As a result, the average load of the
system is incorrectly calculated and the system might not bring
the cpus online to manage the additional load. This
reduces the performance of the system.

To fix this issue, register rq_stats to receive cpufreq policy
notifications. Update the policy's max frequency when a
notification is received and use that value to calculate the load.

Change-Id: Icc78e28c736c170e198f723fd96c13dfb2dafe8a
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
Signed-off-by: Anji Jonnala <anjir@codeaurora.org>
freezer: shorten freezer sleep time using exponential backoff

Date	Wed, 1 May 2013 18:34:59 -0700

All tasks can easily be frozen in under 10 ms, switch to using
an initial 1 ms sleep followed by exponential backoff until
8 ms.  Also convert the printed time to ms instead of centiseconds.

Signed-off-by: Colin Cross <ccross@android.com>
modified for Mako hybrid from LKML

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

Conflicts:
	kernel/power/process.c
freezer: skip waking up tasks with PF_FREEZER_SKIP set

Date	Wed, 1 May 2013 18:35:00 -0700

Android goes through suspend/resume very often (every few seconds when
on a busy wifi network with the screen off), and a significant portion
of the energy used to go in and out of suspend is spent in the
freezer.  If a task has called freezer_do_not_count(), don't bother
waking it up.  If it happens to wake up later it will call
freezer_count() and immediately enter the refrigerator.

Combined with patches to convert freezable helpers to use
freezer_do_not_count() and convert common sites where idle userspace
tasks are blocked to use the freezable helpers, this reduces the
time and energy required to suspend and resume.

Signed-off-by: Colin Cross <ccross@android.com>
freezer: add new freezable helpers using freezer_do_not_count()

Date	Wed, 1 May 2013 18:35:01 -0700

Freezing tasks will wake up almost every userspace task from
where it is blocking and force it to run until it hits a
call to try_to_sleep(), generally on the exit path from the syscall
it is blocking in.  On resume each task will run again, usually
restarting the syscall and running until it hits the same
blocking call as it was originally blocked in.

To allow tasks to avoid running on every suspend/resume cycle,
this patch adds additional freezable wrappers around blocking calls
that call freezer_do_not_count().  Combined with the previous patch,
these tasks will not run during suspend or resume unless they wake
up for another reason, in which case they will run until they hit
the try_to_freeze() in freezer_count(), and then continue processing
the wakeup after tasks are thawed.  This patch also converts the
existing wait_event_freezable* wrappers to use freezer_do_not_count().

Additional patches will convert the most common locations that
userspace blocks in to use freezable helpers.

Signed-off-by: Colin Cross <ccross@android.com>

Conflicts:
	include/linux/freezer.h
binder: use freezable blocking calls

Date	Wed, 1 May 2013 18:35:02 -0700

Avoid waking up every thread sleeping in a binder call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Signed-off-by: Colin Cross <ccross@android.com>
epoll: use freezable blocking call

Date	Wed, 1 May 2013 18:35:03 -0700

Avoid waking up every thread sleeping in an epoll_wait call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Signed-off-by: Colin Cross <ccross@android.com>
select: use freezable blocking call

Date	Wed, 1 May 2013 18:35:04 -0700

Avoid waking up every thread sleeping in a select call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Signed-off-by: Colin Cross <ccross@android.com>
futex: use freezable blocking call

Date	Wed, 1 May 2013 18:35:05 -0700

Avoid waking up every thread sleeping in a futex_wait call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Signed-off-by: Colin Cross <ccross@android.com>
nanosleep: use freezable blocking call

Date	Wed, 1 May 2013 18:35:06 -0700

Avoid waking up every thread sleeping in a nanosleep call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Signed-off-by: Colin Cross <ccross@android.com>
sigtimedwait: use freezable blocking call

Date	Wed, 1 May 2013 18:35:07 -0700

Avoid waking up every thread sleeping in a sigtimedwait call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Signed-off-by: Colin Cross <ccross@android.com>
af_unix: use freezable blocking calls in read

Date	Wed, 1 May 2013 18:35:08 -0700

Avoid waking up every thread sleeping in read call on an AF_UNIX
socket during suspend and resume by calling a freezable blocking
call.  Previous patches modified the freezer to avoid sending
wakeups to threads that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Signed-off-by: Colin Cross <ccross@android.com>