[PATCH v2 0/2] sched/rt: track rt rq utilization

From: Vincent Guittot
Date: Mon Jun 19 2017 - 04:51:54 EST

When both cfs and rt tasks compete to run on a CPU, we can see some frequency
drops with schedutil governor. In such case, the cfs_rq's utilization doesn't
reflect anymore the utilization of cfs tasks but only the remaining part that
is not used by rt tasks. We should monitor the stolen utilization and take
it into account when selecting OPP.

Patch 1 tracks utilization of rt_rq.
Patch 2 adds the rt_rq's utilization when selection OPP for cfs tasks

This patchset doesn't change the OPP selection policy for RT tasks

Change since v1:
- Only a rebase. I have addressed the comments on previous version in
patch 1/2

Vincent Guittot (2):
sched/rt: add utilization tracking
cpufreq/schedutil: add rt utilization tracking

kernel/sched/cpufreq_schedutil.c | 2 +-
kernel/sched/fair.c | 21 +++++++++++++++++++++
kernel/sched/rt.c | 9 +++++++++
kernel/sched/sched.h | 3 +++
4 files changed, 34 insertions(+), 1 deletion(-)