On Thu, Mar 03, 2016 at 12:43:53PM +0100, Thomas Gleixner wrote: > Subject: cpu/hotplug: Handle cpu active as last state > From: Thomas Gleixner <[email protected]> > Date: Thu, 03 Mar 2016 12:33:37 +0100 > > We want to make sure that everything is initialized before we allow scheduling > of arbitrary work on a upcoming CPU and we don't want to have no more random > work on it when we shut it down. > > Now that the scheduler handles this nicely via the cpu_active_mask we can put > set_cpu_active() as last action when a cpu is brought up and as first action > when it goes down. > > Signed-off-by: Thomas Gleixner <[email protected]> > Cc: Peter Zijlstra <[email protected]>
Nice! Acked-by: Peter Zijlstra (Intel) <[email protected]> > --- > include/linux/cpuhotplug.h | 1 + > kernel/cpu.c | 19 +++++++++++++++++-- > kernel/sched/core.c | 18 ------------------ > 3 files changed, 18 insertions(+), 20 deletions(-) > > +++ b/kernel/sched/core.c > @@ -5726,23 +5726,6 @@ static int sched_cpu_active(struct notif > case CPU_STARTING: > set_cpu_rq_start_time(); If we stick that in notify_starting() we can kill all of this. > return NOTIFY_OK; > - > - case CPU_DOWN_FAILED: > - set_cpu_active(cpu, true); > - return NOTIFY_OK; > - > - default: > - return NOTIFY_DONE; > - } > -} > - > -static int sched_cpu_inactive(struct notifier_block *nfb, > - unsigned long action, void *hcpu) > -{ > - switch (action & ~CPU_TASKS_FROZEN) { > - case CPU_DOWN_PREPARE: > - set_cpu_active((long)hcpu, false); > - return NOTIFY_OK; > default: > return NOTIFY_DONE; > } > @@ -5761,7 +5744,6 @@ static int __init migration_init(void) > > /* Register cpu active notifiers */ > cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE); > - cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE); > > return 0; > }
