io_uring: remove extra barrier for non-sqpoll iopoll

Browse source

smp_mb() in io_cqring_ev_posted_iopoll() is only there because of
waitqueue_active(). However, non-SQPOLL IOPOLL ring doesn't wake the CQ
and so the barrier there is useless. Kill it, it's usually pretty
expensive.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d72e8ef6f7a3f6a72e18fad8409f7d47afc8da7d.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

...

This commit is contained in:

Pavel Begunkov 2022-03-17 02:03:39 +00:00 • committed by Jens Axboe

parent b91ef18728

commit 0f84747177

1 changed files with 1 additions and 4 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

5

fs/io_uring.c

View file