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author | Jackie Liu <liuyun01@kylinos.cn> | 2019-05-16 11:46:30 +0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2019-05-16 08:10:25 -0600 |
commit | dc6ce4bc2b355a47f225a0205046b3ebf29a7f72 (patch) | |
tree | 78492c45930982a9d1fae0ce6eed67c2a92597b1 /fs/io_uring.c | |
parent | 2bbcd6d3b36a75a19be4917807f54ae32dd26aba (diff) | |
download | blackbird-op-linux-dc6ce4bc2b355a47f225a0205046b3ebf29a7f72.tar.gz blackbird-op-linux-dc6ce4bc2b355a47f225a0205046b3ebf29a7f72.zip |
io_uring: adjust smp_rmb inside io_cqring_events
Whenever smp_rmb is required to use io_cqring_events,
keep smp_rmb inside the function io_cqring_events.
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
-rw-r--r-- | fs/io_uring.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 67d1aae349d7..9cc7a101ef2a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2167,6 +2167,8 @@ static int io_ring_submit(struct io_ring_ctx *ctx, unsigned int to_submit) static unsigned io_cqring_events(struct io_cq_ring *ring) { + /* See comment at the top of this file */ + smp_rmb(); return READ_ONCE(ring->r.tail) - READ_ONCE(ring->r.head); } @@ -2182,8 +2184,6 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, DEFINE_WAIT(wait); int ret; - /* See comment at the top of this file */ - smp_rmb(); if (io_cqring_events(ring) >= min_events) return 0; @@ -2205,8 +2205,6 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, prepare_to_wait(&ctx->wait, &wait, TASK_INTERRUPTIBLE); ret = 0; - /* See comment at the top of this file */ - smp_rmb(); if (io_cqring_events(ring) >= min_events) break; |