| Message ID | 1409815075-4180-1-git-send-email-chuansheng.liu@intel.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On 09/04/2014 09:17 AM, Chuansheng Liu wrote: > Implementing one new API wake_up_if_idle(), which is used to > wake up the idle CPU. > > Suggested-by: Andy Lutomirski <luto@amacapital.net> > Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com> Hi Chuanseng, in the future, please prefix the patches with the version number and a changelog. Thanks -- Daniel Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> > --- > include/linux/sched.h | 1 + > kernel/sched/core.c | 19 +++++++++++++++++++ > 2 files changed, 20 insertions(+) > > diff --git a/include/linux/sched.h b/include/linux/sched.h > index 857ba40..3f89ac1 100644 > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -1024,6 +1024,7 @@ struct sched_domain_topology_level { > extern struct sched_domain_topology_level *sched_domain_topology; > > extern void set_sched_topology(struct sched_domain_topology_level *tl); > +extern void wake_up_if_idle(int cpu); > > #ifdef CONFIG_SCHED_DEBUG > # define SD_INIT_NAME(type) .name = #type > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 1211575..b818548 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -1620,6 +1620,25 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu) > } > } > > +void wake_up_if_idle(int cpu) > +{ > + struct rq *rq = cpu_rq(cpu); > + unsigned long flags; > + > + if (!is_idle_task(rq->curr)) > + return; > + > + if (set_nr_if_polling(rq->idle)) { > + trace_sched_wake_idle_without_ipi(cpu); > + } else { > + raw_spin_lock_irqsave(&rq->lock, flags); > + if (is_idle_task(rq->curr)) > + smp_send_reschedule(cpu); > + /* Else cpu is not in idle, do nothing here */ > + raw_spin_unlock_irqrestore(&rq->lock, flags); > + } > +} > + > bool cpus_share_cache(int this_cpu, int that_cpu) > { > return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu); >
> -----Original Message----- > From: Daniel Lezcano [mailto:daniel.lezcano@linaro.org] > Sent: Thursday, September 04, 2014 8:53 PM > To: Liu, Chuansheng; peterz@infradead.org; luto@amacapital.net; > rjw@rjwysocki.net; mingo@redhat.com > Cc: linux-pm@vger.kernel.org; linux-kernel@vger.kernel.org; Liu, Changcheng; > Wang, Xiaoming; Chakravarty, Souvik K > Subject: Re: [PATCH 1/3] sched: Add new API wake_up_if_idle() to wake up the > idle cpu > > On 09/04/2014 09:17 AM, Chuansheng Liu wrote: > > Implementing one new API wake_up_if_idle(), which is used to > > wake up the idle CPU. > > > > Suggested-by: Andy Lutomirski <luto@amacapital.net> > > Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com> > > Hi Chuanseng, > > in the future, please prefix the patches with the version number and a > changelog. > Thanks your advice, Daniel, will do that next time:)
diff --git a/include/linux/sched.h b/include/linux/sched.h index 857ba40..3f89ac1 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1024,6 +1024,7 @@ struct sched_domain_topology_level { extern struct sched_domain_topology_level *sched_domain_topology; extern void set_sched_topology(struct sched_domain_topology_level *tl); +extern void wake_up_if_idle(int cpu); #ifdef CONFIG_SCHED_DEBUG # define SD_INIT_NAME(type) .name = #type diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 1211575..b818548 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1620,6 +1620,25 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu) } } +void wake_up_if_idle(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + if (!is_idle_task(rq->curr)) + return; + + if (set_nr_if_polling(rq->idle)) { + trace_sched_wake_idle_without_ipi(cpu); + } else { + raw_spin_lock_irqsave(&rq->lock, flags); + if (is_idle_task(rq->curr)) + smp_send_reschedule(cpu); + /* Else cpu is not in idle, do nothing here */ + raw_spin_unlock_irqrestore(&rq->lock, flags); + } +} + bool cpus_share_cache(int this_cpu, int that_cpu) { return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu);
Implementing one new API wake_up_if_idle(), which is used to wake up the idle CPU. Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com> --- include/linux/sched.h | 1 + kernel/sched/core.c | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+)