io_uring: optimise commit_sqring() for common case
It should be pretty rare to not submitting anything when there is
something in the ring. No need to keep heuristics for this case.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 3398f40..8613eae 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -4501,14 +4501,12 @@ static void io_commit_sqring(struct io_ring_ctx *ctx)
{
struct io_rings *rings = ctx->rings;
- if (ctx->cached_sq_head != READ_ONCE(rings->sq.head)) {
- /*
- * Ensure any loads from the SQEs are done at this point,
- * since once we write the new head, the application could
- * write new data to them.
- */
- smp_store_release(&rings->sq.head, ctx->cached_sq_head);
- }
+ /*
+ * Ensure any loads from the SQEs are done at this point,
+ * since once we write the new head, the application could
+ * write new data to them.
+ */
+ smp_store_release(&rings->sq.head, ctx->cached_sq_head);
}
/*
