From: Yuri Norov <ynorov@xxxxxxxxxxx> For nohz_full CPUs the desirable behavior is to receive interrupts generated by tick_nohz_full_kick_cpu(). But for hard isolation it's obviously not desirable because it breaks isolation. This patch adds check for it. Signed-off-by: Yuri Norov <ynorov@xxxxxxxxxxx> [abelits@xxxxxxxxxxx: updated, only exclude CPUs running isolated tasks] Signed-off-by: Alex Belits <abelits@xxxxxxxxxxx> --- kernel/time/tick-sched.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 6e4cd8459f05..2f82a6daf8fc 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -20,6 +20,7 @@ #include <linux/sched/clock.h> #include <linux/sched/stat.h> #include <linux/sched/nohz.h> +#include <linux/isolation.h> #include <linux/module.h> #include <linux/irq_work.h> #include <linux/posix-timers.h> @@ -268,7 +269,8 @@ static void tick_nohz_full_kick(void) */ void tick_nohz_full_kick_cpu(int cpu) { - if (!tick_nohz_full_cpu(cpu)) + smp_rmb(); + if (!tick_nohz_full_cpu(cpu) || task_isolation_on_cpu(cpu)) return; irq_work_queue_on(&per_cpu(nohz_full_kick_work, cpu), cpu); -- 2.26.2