locking/rwbase: Properly match set_and_save_state() to restore_state()

Peter Zijlstra · Peter Zijlstra · commit 7687201e37fa · 2021-09-15T17:49:15.000+02:00
Noticed while looking at the readers race. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20210909110203.828203010@infradead.org
diff --git a/kernel/locking/rwbase_rt.c b/kernel/locking/rwbase_rt.c
@@ -220,7 +220,7 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb,
 	for (; atomic_read(&rwb->readers);) {
 		/* Optimized out for rwlocks */
 		if (rwbase_signal_pending_state(state, current)) {
-			__set_current_state(TASK_RUNNING);
+			rwbase_restore_current_state();
 			__rwbase_write_unlock(rwb, 0, flags);
 			return -EINTR;
 		}

Original file line number	Diff line number	Diff line change
`@@ -220,7 +220,7 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb,`
`220`	`220`	`for (; atomic_read(&rwb->readers);) {`
`221`	`221`	`/* Optimized out for rwlocks */`
`222`	`222`	`if (rwbase_signal_pending_state(state, current)) {`
`223`		`- __set_current_state(TASK_RUNNING);`
	`223`	`+ rwbase_restore_current_state();`
`224`	`224`	`__rwbase_write_unlock(rwb, 0, flags);`
`225`	`225`	`return -EINTR;`
`226`	`226`	`}`