cpufreq: Remove cpufreq_governor_lock
authorViresh Kumar <viresh.kumar@linaro.org>
Thu, 11 Feb 2016 12:01:13 +0000 (17:31 +0530)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 9 Mar 2016 13:41:01 +0000 (14:41 +0100)
commit99522fe6788f5bf627dce7c20ed9484c933511a3
tree55353e0c03780e911cf855135f32f02565fd9603
parent49f18560f8bac5315047edfb673dd13d56cbcbc9
cpufreq: Remove cpufreq_governor_lock

We used to drop policy->rwsem just before calling __cpufreq_governor()
in some cases earlier and so it was possible that __cpufreq_governor()
ran concurrently via separate threads for the same policy.

In order to guarantee valid state transitions for governors,
'governor_enabled' was required to be protected using some locking
and cpufreq_governor_lock was added for that.

But now __cpufreq_governor() is always called under policy->rwsem,
and 'governor_enabled' is protected against races even without
cpufreq_governor_lock.

Get rid of the extra lock now.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
[ rjw : Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/cpufreq/cpufreq.c
drivers/cpufreq/cpufreq_governor.h