[41/48] rcutorture: Re-use value stored to ->rtort_pipe_count instead of re-reading

Commit Message

Uladzislau Rezki May 7, 2024, 9:35 a.m. UTC

From: linke li <[e-mail]>

Currently, the rcu_torture_pipe_update_one() writes the value (i + 1)
to rp->rtort_pipe_count, then immediately re-reads it in order to compare
it to RCU_TORTURE_PIPE_LEN.  This re-read is pointless because no other
update to rp->rtort_pipe_count can occur at this point.  This commit
therefore instead re-uses the (i + 1) value stored in the comparison
instead of re-reading rp->rtort_pipe_count.

Signed-off-by: linke li <[e-mail]>
Reviewed-by: Joel Fernandes (Google) <[e-mail]>
Signed-off-by: Paul E. McKenney <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Signed-off-by: Uladzislau Rezki (Sony) <[e-mail]>
---
 kernel/rcu/rcutorture.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 0cb5452ecd94..dd7d5ba45740 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -467,7 +467,7 @@  rcu_torture_pipe_update_one(struct rcu_torture *rp)
 	atomic_inc(&rcu_torture_wcount[i]);
 	WRITE_ONCE(rp->rtort_pipe_count, i + 1);
 	ASSERT_EXCLUSIVE_WRITER(rp->rtort_pipe_count);
-	if (rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) {
+	if (i + 1 >= RCU_TORTURE_PIPE_LEN) {
 		rp->rtort_mbtest = 0;
 		return true;
 	}