Re: [PATCH 03/11] cpufreq/schedutil: use rt utilization tracking
On 28-06-18, 17:45, Vincent Guittot wrote: > Add both cfs and rt utilization when selecting an OPP for cfs tasks as rt > can preempt and steal cfs's running time. > > rt util_avg is used to take into account the utilization of rt tasks > on the CPU when selecting OPP. If a rt task migrate, the rt utilization > will not migrate but will decay over time. On an overloaded CPU, cfs > utilization reflects the remaining utilization avialable on CPU. When rt > task migrates, the cfs utilization will increase when tasks will start to > use the newly available capacity. At the same pace, rt utilization will > decay and both variations will compensate each other to keep unchanged > overall utilization and will prevent any OPP drop. > > Cc: Ingo Molnar > Cc: Peter Zijlstra > Signed-off-by: Vincent Guittot > --- > kernel/sched/cpufreq_schedutil.c | 9 - > 1 file changed, 8 insertions(+), 1 deletion(-) Acked-by: Viresh Kumar -- viresh
Re: [PATCH 03/11] cpufreq/schedutil: use rt utilization tracking
On 28-06-18, 17:45, Vincent Guittot wrote: > Add both cfs and rt utilization when selecting an OPP for cfs tasks as rt > can preempt and steal cfs's running time. > > rt util_avg is used to take into account the utilization of rt tasks > on the CPU when selecting OPP. If a rt task migrate, the rt utilization > will not migrate but will decay over time. On an overloaded CPU, cfs > utilization reflects the remaining utilization avialable on CPU. When rt > task migrates, the cfs utilization will increase when tasks will start to > use the newly available capacity. At the same pace, rt utilization will > decay and both variations will compensate each other to keep unchanged > overall utilization and will prevent any OPP drop. > > Cc: Ingo Molnar > Cc: Peter Zijlstra > Signed-off-by: Vincent Guittot > --- > kernel/sched/cpufreq_schedutil.c | 9 - > 1 file changed, 8 insertions(+), 1 deletion(-) Acked-by: Viresh Kumar -- viresh