xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

cpufreq: Allow light-weight tear down and bring up of CPUs

Browse Source 
The cpufreq core doesn't remove the cpufreq policy anymore on CPU
offline operation, rather that happens when the CPU device gets
unregistered from the kernel. This allows faster recovery when the CPU
comes back online. This is also very useful during system wide
suspend/resume where we offline all non-boot CPUs during suspend and
then bring them back on resume.

This commit takes the same idea a step ahead to allow drivers to do
light weight tear-down and bring-up during CPU offline and online
operations.

A new set of callbacks is introduced, online/offline(). online() gets
called when the first CPU of an inactive policy is brought up and
offline() gets called when all the CPUs of a policy are offlined.

The existing init/exit() callback get called on policy
creation/destruction. They also get called instead of online/offline()
callbacks if the online/offline() callbacks aren't provided.

This also moves around some code to get executed only for the new-policy
case going forward.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Viresh Kumar
2019-02-12 16:36:04 +05:30
committed by Rafael J. Wysocki
parent 9795607dc4
commit 91a12e91dc
2 changed files with 40 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
include/linux/cpufreq.h
View File

@@ -325,6 +325,8 @@ struct cpufreq_driver {
/* optional */
int (*bios_limit)(int cpu, unsigned int *limit);
int (*online)(struct cpufreq_policy *policy);
int (*offline)(struct cpufreq_policy *policy);
int (*exit)(struct cpufreq_policy *policy);
void (*stop_cpu)(struct cpufreq_policy *policy);
int (*suspend)(struct cpufreq_policy *policy);