[PATCH V2 0/4] cpufreq: Record stats with fast-switching

From: Viresh Kumar
Date: Wed Sep 16 2020 - 02:45:43 EST


Hi,

We disabled recording cpufreq stats when fast switching was introduced
to the cpufreq core as the cpufreq stats required to take a spinlock and
that can't be allowed (for performance reasons) on scheduler's hot path.

Here is an attempt to get rid of the lock and bring back the support.

V1-V2:
- Use READ_ONCE/WRITE_ONCE instead of atomic in the first patch.

--
Viresh

Viresh Kumar (4):
cpufreq: stats: Defer stats update to
cpufreq_stats_record_transition()
cpufreq: stats: Remove locking
cpufreq: stats: Enable stats for fast-switch as well
cpufreq: Move traces and update to policy->cur to cpufreq core

drivers/cpufreq/cpufreq.c | 16 +++++-
drivers/cpufreq/cpufreq_stats.c | 87 ++++++++++++++++++++------------
kernel/sched/cpufreq_schedutil.c | 12 +----
3 files changed, 72 insertions(+), 43 deletions(-)


base-commit: 856deb866d16e29bd65952e0289066f6078af773
--
2.25.0.rc1.19.g042ed3e048af