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io_uring: micro optimization of __io_sq_thread() condition

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reverse the order of the element evaluation in an if statement.

for many users that are not using iopoll, the iopoll_list will always
evaluate to false after having made a memory access whereas to_submit is
very likely already loaded in a register.

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/052ca60b5c49e7439e4b8bd33bfab4a09d36d3d6.1722374371.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Olivier Langlois 2024-07-30 16:56:06 -04:00 committed by Jens Axboe
parent a8edbb424b
commit 7255cd8945
1 changed files with 1 additions and 1 deletions
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io_uring/sqpoll.c
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@ -176,7 +176,7 @@ static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
if (!wq_list_empty(&ctx->iopoll_list) || to_submit) {
if (to_submit || !wq_list_empty(&ctx->iopoll_list)) {
const struct cred *creds = NULL;
if (ctx->sq_creds != current_cred())