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).
@Srivatsa: Can you please have a look at the above change? I have cc'd you only on this one.
Saravana Kannan (1): cpufreq: Track cpu managing sysfs kobjects separately
Cc: Srivatsa Bhat srivatsa@mit.edu
Viresh Kumar (19): cpufreq: Add doc style comment about cpufreq_cpu_{get|put}() cpufreq: Merge __cpufreq_add_dev() and cpufreq_add_dev() cpufreq: Throw warning when we try to get policy for an invalid CPU cpufreq: Keep a single path for adding managed CPUs cpufreq: Clear policy->cpus even for the last CPU cpufreq: Create for_each_{in}active_policy() cpufreq: Call schedule_work() for the last active policy cpufreq: Don't clear cpufreq_cpu_data and policy list for inactive policies cpufreq: Get rid of cpufreq_cpu_data_fallback cpufreq: Don't traverse list of all policies for adding policy for a cpu cpufreq: Manage governor usage history with 'policy->last_governor' cpufreq: Mark policy->governor = NULL for inactive policies cpufreq: Don't allow updating inactive-policies from sysfs cpufreq: Stop migrating sysfs files on hotplug cpufreq: Remove cpufreq_update_policy() cpufreq: Initialize policy->kobj while allocating policy cpufreq: Call cpufreq_policy_put_kobj() from cpufreq_policy_free() cpufreq: Restart governor as soon as possible cpufreq: Add support for physical hoplug of CPUs
drivers/cpufreq/cpufreq.c | 593 ++++++++++++++++++++++++++-------------------- include/linux/cpufreq.h | 5 +- 2 files changed, 340 insertions(+), 258 deletions(-)