RDMA/rxe: Merge request and complete tasks

Currently the rxe driver has three work queue tasks per qp.  These are the
req.task, comp.task and resp.task which call rxe_requester(),
rxe_completer() and rxe_responder() respectively directly or on work
queues. Each of these subroutines checks to see if there is work to be
performed on the send queue or on the response packet queue or the request
packet queue and will run until there is no work remaining or yield the
cpu and reschedule itself until there is no work remaining.

This commit combines the req.task and comp.task into a single send.task
and renames the resp.task to the recv.task. The combined send.task calls
rxe_requester() and rxe_completer() serially and continues until all work
on both the send queue and the response packet queue are done.

In various benchmarks the performance is either improved or left the
same. At high scale there is a significant reduction in the load on the
cpu.

This is the first step in combining these two tasks. Once they are
serialized cross rescheduling of req.task and comp.task can be more
efficiently handled by just letting the send.task continue to run. This
will be done in the next several patches.

Link: https://lore.kernel.org/r/20240329145513.35381-7-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
index ccb9d19ffe8a..af8939b8c7a1 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -113,7 +113,6 @@ struct rxe_req_info {
 	int			need_retry;
 	int			wait_for_rnr_timer;
 	int			noack_pkts;
-	struct rxe_task		task;
 };
 
 struct rxe_comp_info {
@@ -124,7 +123,6 @@ struct rxe_comp_info {
 	int			started_retry;
 	u32			retry_cnt;
 	u32			rnr_retry;
-	struct rxe_task		task;
 };
 
 enum rdatm_res_state {
@@ -196,7 +194,6 @@ struct rxe_resp_info {
 	unsigned int		res_head;
 	unsigned int		res_tail;
 	struct resp_res		*res;
-	struct rxe_task		task;
 };
 
 struct rxe_qp {
@@ -229,6 +226,9 @@ struct rxe_qp {
 	struct sk_buff_head	req_pkts;
 	struct sk_buff_head	resp_pkts;
 
+	struct rxe_task		send_task;
+	struct rxe_task		recv_task;
+
 	struct rxe_req_info	req;
 	struct rxe_comp_info	comp;
 	struct rxe_resp_info	resp;