Messages in this thread Patch in this message | | | From | Davidlohr Bueso <> | Subject | [PATCH] kernel/futex: Fix barrier comment | Date | Wed, 6 Feb 2019 10:56:02 -0800 |
| |
The current comment for the barrier that guarantees that waiter increment is always before taking the hb spinlock (barrier (A)) needs to be fixed. We are obviously referring to hb_waiters_inc, which is a full barrier.
Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Davidlohr Bueso <dbueso@suse.de> --- kernel/futex.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/futex.c b/kernel/futex.c index fdd312da0992..5ec2473a3497 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2221,11 +2221,11 @@ static inline struct futex_hash_bucket *queue_lock(struct futex_q *q) * decrement the counter at queue_unlock() when some error has * occurred and we don't end up adding the task to the list. */ - hb_waiters_inc(hb); + hb_waiters_inc(hb); /* implies smp_mb(); (A) */ q->lock_ptr = &hb->lock; - spin_lock(&hb->lock); /* implies smp_mb(); (A) */ + spin_lock(&hb->lock); return hb; } -- 2.16.4
| |