Commit 467f16bf authored by Ziye Yang's avatar Ziye Yang Committed by Tomasz Zawadzki
Browse files

uring: Use low level list ops to improve the performance when reorder the list. 



This patch is used to improve the performance when
we need to reorder the list.

PS: Bring the similar operations from posix implementation.

Signed-off-by: default avatarZiye Yang <ziye.yang@intel.com>
Change-Id: I7031b35ddb597730ee160690e8ab9caf9b2b64b7
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/8675


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Community-CI: Mellanox Build Bot
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarAleksey Marchuk <alexeymar@mellanox.com>
parent bd4aec1c

module/sock/uring/uring.c

+41 −16
Original line number Diff line number Diff line
@@ -90,13 +90,15 @@ struct spdk_uring_sock { 
	TAILQ_ENTRY(spdk_uring_sock)		link;

};



TAILQ_HEAD(pending_recv_list, spdk_uring_sock);



struct spdk_uring_sock_group_impl {

	struct spdk_sock_group_impl		base;

	struct io_uring				uring;

	uint32_t				io_inflight;

	uint32_t				io_queued;

	uint32_t				io_avail;

	TAILQ_HEAD(, spdk_uring_sock)		pending_recv;

	struct pending_recv_list		pending_recv;

};



static struct spdk_sock_impl_opts g_spdk_uring_sock_impl_opts = {
@@ -941,29 +943,52 @@ sock_uring_group_reap(struct spdk_uring_sock_group_impl *group, int max, int max 
			break;

		}



		/* If the socket's cb_fn is NULL, just remove it from

		 * the list and do not add it to socks array */

		if (spdk_unlikely(sock->base.cb_fn == NULL)) {

		if (spdk_unlikely(sock->base.cb_fn == NULL) ||

		    (sock->recv_pipe == NULL || spdk_pipe_reader_bytes_available(sock->recv_pipe) == 0)) {

			sock->pending_recv = false;

			TAILQ_REMOVE(&group->pending_recv, sock, link);

			if (spdk_unlikely(sock->base.cb_fn == NULL)) {

				/* If the socket's cb_fn is NULL, do not add it to socks array */

				continue;

			}

		}



		socks[count++] = &sock->base;

	}





	/* Cycle the pending_recv list so that each time we poll things aren't

	 * in the same order. */

	for (i = 0; i < count; i++) {

		sock = __uring_sock(socks[i]);

	 * in the same order. Say we have 6 sockets in the list, named as follows:

	 * A B C D E F

	 * And all 6 sockets had the poll events, but max_events is only 3. That means

	 * psock currently points at D. We want to rearrange the list to the following:

	 * D E F A B C

	 *

	 * The variables below are named according to this example to make it easier to

	 * follow the swaps.

	 */

	if (sock != NULL) {

		struct spdk_uring_sock *ua, *uc, *ud, *uf;



		TAILQ_REMOVE(&group->pending_recv, sock, link);

		/* Capture pointers to the elements we need */

		ud = sock;

		uc = TAILQ_PREV(ud, pending_recv_list, link);

		ua = TAILQ_FIRST(&group->pending_recv);

		uf = TAILQ_LAST(&group->pending_recv, pending_recv_list);



		if (sock->recv_pipe == NULL || spdk_pipe_reader_bytes_available(sock->recv_pipe) == 0) {

			sock->pending_recv = false;

		} else {

			TAILQ_INSERT_TAIL(&group->pending_recv, sock, link);

		}

		/* Break the link between C and D */

		uc->link.tqe_next = NULL;



		/* Connect F to A */

		uf->link.tqe_next = ua;

		ua->link.tqe_prev = &uf->link.tqe_next;



		/* Fix up the list first/last pointers */

		group->pending_recv.tqh_first = ud;

		group->pending_recv.tqh_last = &uc->link.tqe_next;



		/* D is in front of the list, make tqe prev pointer point to the head of list */

		ud->link.tqe_prev = &group->pending_recv.tqh_first;

	}



	return count;