| Message ID | 1349595838-31274-6-git-send-email-vincent.guittot@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sunday 07 October 2012 01:13 PM, Vincent Guittot wrote: > Look for an idle CPU close the pack buddy CPU whenever possible. s/close/close to > The goal is to prevent the wake up of a CPU which doesn't share the power > line of the pack CPU > > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> > --- > kernel/sched/fair.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 6df53b5..f76acdc 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -5158,7 +5158,25 @@ static struct { > > static inline int find_new_ilb(int call_cpu) > { > + struct sched_domain *sd; > int ilb = cpumask_first(nohz.idle_cpus_mask); > + int buddy = per_cpu(sd_pack_buddy, call_cpu); > + > + /* > + * If we have a pack buddy CPU, we try to run load balance on a CPU > + * that is close to the buddy. > + */ > + if (buddy != -1) > + for_each_domain(buddy, sd) { > + if (sd->flags & SD_SHARE_CPUPOWER) > + continue; Do you mean SD_SHARE_POWERLINE here ? > + > + ilb = cpumask_first_and(sched_domain_span(sd), > + nohz.idle_cpus_mask); > + > + if (ilb < nr_cpu_ids) > + break; > + } > > if (ilb < nr_cpu_ids && idle_cpu(ilb)) > return ilb; > Can you please expand "idle CPU _close_ the pack buddy CPU" ? Regards santosh
On 24 October 2012 17:21, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote: > On Sunday 07 October 2012 01:13 PM, Vincent Guittot wrote: >> >> Look for an idle CPU close the pack buddy CPU whenever possible. > > s/close/close to yes > >> The goal is to prevent the wake up of a CPU which doesn't share the power >> line of the pack CPU >> >> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> >> --- >> kernel/sched/fair.c | 18 ++++++++++++++++++ >> 1 file changed, 18 insertions(+) >> >> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >> index 6df53b5..f76acdc 100644 >> --- a/kernel/sched/fair.c >> +++ b/kernel/sched/fair.c >> @@ -5158,7 +5158,25 @@ static struct { >> >> static inline int find_new_ilb(int call_cpu) >> { >> + struct sched_domain *sd; >> int ilb = cpumask_first(nohz.idle_cpus_mask); >> + int buddy = per_cpu(sd_pack_buddy, call_cpu); >> + >> + /* >> + * If we have a pack buddy CPU, we try to run load balance on a >> CPU >> + * that is close to the buddy. >> + */ >> + if (buddy != -1) >> + for_each_domain(buddy, sd) { >> + if (sd->flags & SD_SHARE_CPUPOWER) >> + continue; > > Do you mean SD_SHARE_POWERLINE here ? No, I just don't want to take hyperthread level for ILB > >> + >> + ilb = cpumask_first_and(sched_domain_span(sd), >> + nohz.idle_cpus_mask); >> + >> + if (ilb < nr_cpu_ids) >> + break; >> + } >> >> if (ilb < nr_cpu_ids && idle_cpu(ilb)) >> return ilb; >> > Can you please expand "idle CPU _close_ the pack buddy CPU" ? The goal is to packed the tasks on the pack buddy CPU so when the scheduler needs to start ILB, I try to wake up a CPU that is close to the buddy and preferably in the same cluster > > Regards > santosh
On Monday 29 October 2012 06:57 PM, Vincent Guittot wrote: > On 24 October 2012 17:21, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote: >> On Sunday 07 October 2012 01:13 PM, Vincent Guittot wrote: >>> >>> Look for an idle CPU close the pack buddy CPU whenever possible. >> >> s/close/close to > > yes > >> >>> The goal is to prevent the wake up of a CPU which doesn't share the power >>> line of the pack CPU >>> >>> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> >>> --- >>> kernel/sched/fair.c | 18 ++++++++++++++++++ >>> 1 file changed, 18 insertions(+) >>> >>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >>> index 6df53b5..f76acdc 100644 >>> --- a/kernel/sched/fair.c >>> +++ b/kernel/sched/fair.c >>> @@ -5158,7 +5158,25 @@ static struct { >>> >>> static inline int find_new_ilb(int call_cpu) >>> { >>> + struct sched_domain *sd; >>> int ilb = cpumask_first(nohz.idle_cpus_mask); >>> + int buddy = per_cpu(sd_pack_buddy, call_cpu); >>> + >>> + /* >>> + * If we have a pack buddy CPU, we try to run load balance on a >>> CPU >>> + * that is close to the buddy. >>> + */ >>> + if (buddy != -1) >>> + for_each_domain(buddy, sd) { >>> + if (sd->flags & SD_SHARE_CPUPOWER) >>> + continue; >> >> Do you mean SD_SHARE_POWERLINE here ? > > No, I just don't want to take hyperthread level for ILB > >> >>> + >>> + ilb = cpumask_first_and(sched_domain_span(sd), >>> + nohz.idle_cpus_mask); >>> + >>> + if (ilb < nr_cpu_ids) >>> + break; >>> + } >>> >>> if (ilb < nr_cpu_ids && idle_cpu(ilb)) >>> return ilb; >>> >> Can you please expand "idle CPU _close_ the pack buddy CPU" ? > > The goal is to packed the tasks on the pack buddy CPU so when the > scheduler needs to start ILB, I try to wake up a CPU that is close to > the buddy and preferably in the same cluster > I see your point now. Thanks for clarification. Regards santosh
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6df53b5..f76acdc 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5158,7 +5158,25 @@ static struct { static inline int find_new_ilb(int call_cpu) { + struct sched_domain *sd; int ilb = cpumask_first(nohz.idle_cpus_mask); + int buddy = per_cpu(sd_pack_buddy, call_cpu); + + /* + * If we have a pack buddy CPU, we try to run load balance on a CPU + * that is close to the buddy. + */ + if (buddy != -1) + for_each_domain(buddy, sd) { + if (sd->flags & SD_SHARE_CPUPOWER) + continue; + + ilb = cpumask_first_and(sched_domain_span(sd), + nohz.idle_cpus_mask); + + if (ilb < nr_cpu_ids) + break; + } if (ilb < nr_cpu_ids && idle_cpu(ilb)) return ilb;
Look for an idle CPU close the pack buddy CPU whenever possible. The goal is to prevent the wake up of a CPU which doesn't share the power line of the pack CPU Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> --- kernel/sched/fair.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)