CPU hotplug, debug: detect imbalance between get_online_cpus() and put_online_cpus()

The synchronization between CPU hotplug readers and writers is achieved
by means of refcounting, safeguarded by the cpu_hotplug.lock.

get_online_cpus() increments the refcount, whereas put_online_cpus()
decrements it.  If we ever hit an imbalance between the two, we end up
compromising the guarantees of the hotplug synchronization i.e, for
example, an extra call to put_online_cpus() can end up allowing a
hotplug reader to execute concurrently with a hotplug writer.

So, add a WARN_ON() in put_online_cpus() to detect such cases where the
refcount can go negative, and also attempt to fix it up, so that we can
continue to run.

Change-Id: I144efeaa5899a2e8a3cddd21f010679cbaaa2459
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 075663d19885eb3738fd2d7dbdb8947e12563b68
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Osvaldo Banuelos <osvaldob@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
cpufreq: Optimize cpufreq_frequency_table_verify()

cpufreq_frequency_table_verify() is rewritten here to make it more logical
and efficient.
 - merge multiple lines for variable declarations together.
 - quit early if any frequency between min/max is found.
 - don't call cpufreq_verify_within_limits() in case any valid freq is
   found as it is of no use.
 - rename the count variable as found and change its type to boolean.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
msm: gpu: merge algorithm improvements from hammerhead.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>

Conflicts:
	drivers/gpu/msm/kgsl_pwrscale_trustzone.c
msm: kgsl: small calculation change.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
msm: kgsl: no need to cast long because jiffies and window_time are already long.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
msm: kgsl: change the load calculation equation & fix a couple of bugs, one of 'em was keeping the GPU on 320MHz if the GPU was not sleeping.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
msm: kgsl: don't forcefully ramp down on sleep if there's still load higher than down_threshold.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
msm: kgsl: remove the sample_time_ms and let the governor run its idle_check freely like Qualcomm intends. I was seeing some frames being lost because the sample_time_ms was too big.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
msm: kgsl: remove obsolete code.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>