On 02/26/2015 09:26 PM, Viresh Kumar wrote:

On 19 February 2015 at 17:02, Viresh Kumar [off-list ref] wrote:

quoted

Hi Rafael,

The aim of this series is to stop managing cpufreq sysfs directories on CPU
hotplugs.

Currently on removal of a 'cpu != policy->cpu', we remove its sysfs directories
by removing the soft-link. And on removal of policy->cpu, we migrate the sysfs
directories to the next cpu. But if policy->cpu was the last CPU, we remove the
policy completely and allocate it again as soon as the CPUs come back. This has
shortcomings:

- Code Complexity
- Slower hotplug
- sysfs file permissions are reset after all policy->cpus are offlined
- CPUFreq stats history lost after all policy->cpus are offlined
- Special management of sysfs stuff during suspend/resume


To make things simple we stop playing with sysfs files unless the driver is
getting removed. Also the policy is kept intact to be used later.

First few patches provide a clean base for others *more important* patches.

Rebased-over: your bleeding edge branch as there were dependencies on my earlier
patches.

Pushed here:

git://git.linaro.org/people/viresh.kumar/linux.git cpufreq/core/sysfs

v1->V2:
- Dropped the idea of using policy-lists for getting policy for any cpu
- Also dropped fallback list and its per-cpu variable
- Stopped cleaning cpufreq_cpu_data and doing list_del(policy) on logical
   hotplug.
- Added support for physical hotplug of CPUs (Untested).

Gentle reminder for reviews !! :)

Sorry, caught up on some internal work. Should be able to get to this by 
Wednesday.

-Saravana

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