[PATCH v3 3/6] sched: Change wait_task_inactive()s match_state

[Peter Zijlstra]

Make wait_task_inactive()'s @match_state work like ttwu()'s @state.

That is, instead of an equal comparison, use it as a mask. This allows
matching multiple block conditions.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 kernel/sched/core.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3295,7 +3295,7 @@ unsigned long wait_task_inactive(struct
 		 * is actually now running somewhere else!
 		 */
 		while (task_running(rq, p)) {
-			if (match_state && unlikely(READ_ONCE(p->__state) != match_state))
+			if (match_state && !(READ_ONCE(p->__state) & match_state))
 				return 0;
 			cpu_relax();
 		}
@@ -3310,7 +3310,7 @@ unsigned long wait_task_inactive(struct
 		running = task_running(rq, p);
 		queued = task_on_rq_queued(p);
 		ncsw = 0;
-		if (!match_state || READ_ONCE(p->__state) == match_state)
+		if (!match_state || (READ_ONCE(p->__state) & match_state))
 			ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
 		task_rq_unlock(rq, p, &rf);