sched/core: Add preempt argument to __schedule()

There is only a single PREEMPT_ACTIVE use in the regular __schedule()
path and that is to circumvent the task->state check. Since the code
setting PREEMPT_ACTIVE is the immediate caller of __schedule() we can
replace this with a function argument.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 8d8722b84dee752b1f2067e1932708c5c4704dd7..0a71f89fb3fc189abfac537fe8b53211c00bca84 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3056,7 +3056,7 @@ again:
  *
  * WARNING: must be called with preemption disabled!
  */
-static void __sched __schedule(void)
+static void __sched __schedule(bool preempt)
 {
        struct task_struct *prev, *next;
        unsigned long *switch_count;
@@ -3096,7 +3096,7 @@ static void __sched __schedule(void)
        rq->clock_skip_update <<= 1; /* promote REQ to ACT */
 
        switch_count = &prev->nivcsw;
-       if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
+       if (!preempt && prev->state) {
                if (unlikely(signal_pending_state(prev->state, prev))) {
                        prev->state = TASK_RUNNING;
                } else {
@@ -3161,7 +3161,7 @@ asmlinkage __visible void __sched schedule(void)
        sched_submit_work(tsk);
        do {
                preempt_disable();
-               __schedule();
+               __schedule(false);
                sched_preempt_enable_no_resched();
        } while (need_resched());
 }
@@ -3202,7 +3202,7 @@ static void __sched notrace preempt_schedule_common(void)
 {
        do {
                preempt_active_enter();
-               __schedule();
+               __schedule(true);
                preempt_active_exit();
 
                /*
@@ -3267,7 +3267,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
                 * an infinite recursion.
                 */
                prev_ctx = exception_enter();
-               __schedule();
+               __schedule(true);
                exception_exit(prev_ctx);
 
                barrier();
@@ -3296,7 +3296,7 @@ asmlinkage __visible void __sched preempt_schedule_irq(void)
        do {
                preempt_active_enter();
                local_irq_enable();
-               __schedule();
+               __schedule(true);
                local_irq_disable();
                preempt_active_exit();
        } while (need_resched());