* [PATCH] io_uring: remove extra check in __io_commit_cqring
@ 2020-01-17 0:52 Pavel Begunkov
2020-01-17 2:59 ` Jens Axboe
0 siblings, 1 reply; 2+ messages in thread
From: Pavel Begunkov @ 2020-01-17 0:52 UTC (permalink / raw)
To: Jens Axboe, io-uring, linux-kernel
__io_commit_cqring() is almost always called when there is a change in
the rings, so the check is rather pessimising.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
fs/io_uring.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index f9709a3a673c..ea91f4d92fc0 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -859,14 +859,12 @@ static void __io_commit_cqring(struct io_ring_ctx *ctx)
{
struct io_rings *rings = ctx->rings;
- if (ctx->cached_cq_tail != READ_ONCE(rings->cq.tail)) {
- /* order cqe stores with ring update */
- smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
+ /* order cqe stores with ring update */
+ smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
- if (wq_has_sleeper(&ctx->cq_wait)) {
- wake_up_interruptible(&ctx->cq_wait);
- kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
- }
+ if (wq_has_sleeper(&ctx->cq_wait)) {
+ wake_up_interruptible(&ctx->cq_wait);
+ kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
}
}
--
2.24.0
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] io_uring: remove extra check in __io_commit_cqring
2020-01-17 0:52 [PATCH] io_uring: remove extra check in __io_commit_cqring Pavel Begunkov
@ 2020-01-17 2:59 ` Jens Axboe
0 siblings, 0 replies; 2+ messages in thread
From: Jens Axboe @ 2020-01-17 2:59 UTC (permalink / raw)
To: Pavel Begunkov, io-uring, linux-kernel
On 1/16/20 5:52 PM, Pavel Begunkov wrote:
> __io_commit_cqring() is almost always called when there is a change in
> the rings, so the check is rather pessimising.
Applied, thanks.
--
Jens Axboe
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2020-01-17 3:00 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-01-17 0:52 [PATCH] io_uring: remove extra check in __io_commit_cqring Pavel Begunkov
2020-01-17 2:59 ` Jens Axboe
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).