io_uring: optimise commit_sqring() for common case (caf582c6) · Commits · 戴 / test

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:

fs/io_uring.c

+6 −8

Original line number	Diff line number	Diff line
		@@ -4501,7 +4501,6 @@ 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
		@@ -4509,7 +4508,6 @@ static void io_commit_sqring(struct io_ring_ctx *ctx)
		*/
		smp_store_release(&rings->sq.head, ctx->cached_sq_head);
		}
		}

		/*
		* Fetch an sqe, if one is available. Note that sqe_ptr will point to memory