diff --git a/kernel/sched.c b/kernel/sched.c index 3abd8f780dae..f37a9618fac3 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3636,7 +3636,6 @@ need_resched: rq = cpu_rq(cpu); rcu_note_context_switch(cpu); prev = rq->curr; - switch_count = &prev->nivcsw; release_kernel_lock(prev); need_resched_nonpreemptible: @@ -3649,6 +3648,7 @@ need_resched_nonpreemptible: raw_spin_lock_irq(&rq->lock); clear_tsk_need_resched(prev); + switch_count = &prev->nivcsw; if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { if (unlikely(signal_pending_state(prev->state, prev))) { prev->state = TASK_RUNNING; @@ -3689,8 +3689,10 @@ need_resched_nonpreemptible: context_switch(rq, prev, next); /* unlocks the rq */ /* - * the context switch might have flipped the stack from under - * us, hence refresh the local variables. + * The context switch have flipped the stack from under us + * and restored the local variables which were saved when + * this task called schedule() in the past. prev == current + * is still correct, but it can be moved to another cpu/rq. */ cpu = smp_processor_id(); rq = cpu_rq(cpu); @@ -3699,11 +3701,8 @@ need_resched_nonpreemptible: post_schedule(rq); - if (unlikely(reacquire_kernel_lock(current) < 0)) { - prev = rq->curr; - switch_count = &prev->nivcsw; + if (unlikely(reacquire_kernel_lock(prev))) goto need_resched_nonpreemptible; - } preempt_enable_no_resched(); if (need_resched())