From: Sebastian Andrzej Siewior Date: Mon, 24 Jun 2019 19:33:16 +0200 Subject: [PATCH 269/342] sched/core: Drop a preempt_disable_rt() statement Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=74d2e1a7300ec02a7bea54ed43fbabaa4e8e1193 [ Upstream commit 761126efdcbe3fa3e99c9079fa0ad6eca2f251f2 ] The caller holds a lock which already disables preemption. Drop the preempt_disable_rt() statement in get_nohz_timer_target(). Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Steven Rostedt (VMware) --- kernel/sched/core.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index feaf4d5683af..3b0f62be3ece 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -558,14 +558,11 @@ void resched_cpu(int cpu) */ int get_nohz_timer_target(void) { - int i, cpu; + int i, cpu = smp_processor_id(); struct sched_domain *sd; - preempt_disable_rt(); - cpu = smp_processor_id(); - if (!idle_cpu(cpu) && housekeeping_cpu(cpu, HK_FLAG_TIMER)) - goto preempt_en_rt; + return cpu; rcu_read_lock(); for_each_domain(cpu, sd) { @@ -584,8 +581,6 @@ int get_nohz_timer_target(void) cpu = housekeeping_any_cpu(HK_FLAG_TIMER); unlock: rcu_read_unlock(); -preempt_en_rt: - preempt_enable_rt(); return cpu; }