cpufreq: Simplify __cpufreq_remove_dev()

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__cpufreq_remove_dev() is called on multiple occasions: cpufreq_driver
unregister and cpu removals.

Current implementation of this routine is overly complex without much need. If
the cpu to be removed is the policy->cpu, we remove the policy first and add all
other cpus again from policy->cpus and then finally call __cpufreq_remove_dev()
again to remove the cpu to be deleted. Haahhhh..

There exist a simple solution to removal of a cpu:
- Simply use the old policy structure
- update its fields like: policy->cpu, etc.
- notify any users of cpufreq, which depend on changing policy->cpu

Hence this patch, which tries to implement the above theory. It is tested well
by myself on ARM big.LITTLE TC2 SoC, which has 5 cores (2 A15 and 3 A7). Both
A15's share same struct policy and all A7's share same policy structure.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

...

This commit is contained in:

Viresh Kumar 2013-01-14 13:23:03 +00:00 • committed by Rafael J. Wysocki

parent f85178048c

commit b8eed8af94

4 changed files with 113 additions and 98 deletions

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175

drivers/cpufreq/cpufreq.c

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27

drivers/cpufreq/cpufreq_stats.c

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9

drivers/cpufreq/freq_table.c

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14

include/linux/cpufreq.h

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