RDMA/rtrs: Move sq_wr_avail to rtrs_con

In order to account HB for sq_wr_avail properly, move sq_wr_avail from
rtrs_srv_con to rtrs_con.

Although rtrs-clt do not care sq_wr_avail, but still init it to
max_send_wr.

Fixes: b38041d5 ("RDMA/rtrs: Do not signal for heatbeat")
Link: https://lore.kernel.org/r/20210712060750.16494-7-jinpu.wang@ionos.comSigned-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Aleksei Marov <aleksei.marov@ionos.com>
Reviewed-by: Gioh Kim <gi-oh.kim@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/ulp/rtrs/rtrs-clt.c

@@ -1680,6 +1680,7 @@ static int create_con_cq_qp(struct rtrs_clt_con *con)
 			      sess->queue_depth * 3 + 1);
 		max_send_sge = 2;
 	}
+	atomic_set(&con->c.sq_wr_avail, max_send_wr);
 	cq_num = max_send_wr + max_recv_wr;
 	/* alloc iu to recv new rkey reply when server reports flags set */
 	if (sess->flags & RTRS_MSG_NEW_RKEY_F || con->c.cid == 0) {

drivers/infiniband/ulp/rtrs/rtrs-pri.h

@@ -97,6 +97,7 @@ struct rtrs_con {
 	unsigned int		cid;
 	int                     nr_cqe;
 	atomic_t		wr_cnt;
+	atomic_t		sq_wr_avail;
 };
 
 struct rtrs_sess {

drivers/infiniband/ulp/rtrs/rtrs-srv.c

@@ -507,11 +507,11 @@ bool rtrs_srv_resp_rdma(struct rtrs_srv_op *id, int status)
 		ib_update_fast_reg_key(mr->mr, ib_inc_rkey(mr->mr->rkey));
 	}
 	if (unlikely(atomic_sub_return(1,
-				       &con->sq_wr_avail) < 0)) {
+				       &con->c.sq_wr_avail) < 0)) {
 		rtrs_err(s, "IB send queue full: sess=%s cid=%d\n",
 			 kobject_name(&sess->kobj),
 			 con->c.cid);
-		atomic_add(1, &con->sq_wr_avail);
+		atomic_add(1, &con->c.sq_wr_avail);
 		spin_lock(&con->rsp_wr_wait_lock);
 		list_add_tail(&id->wait_list, &con->rsp_wr_wait_list);
 		spin_unlock(&con->rsp_wr_wait_lock);
@@ -1268,7 +1268,7 @@ static void rtrs_srv_rdma_done(struct ib_cq *cq, struct ib_wc *wc)
 		 * post_send() RDMA write completions of IO reqs (read/write)
 		 * and hb.
 		 */
-		atomic_add(s->signal_interval, &con->sq_wr_avail);
+		atomic_add(s->signal_interval, &con->c.sq_wr_avail);
 
 		if (unlikely(!list_empty_careful(&con->rsp_wr_wait_list)))
 			rtrs_rdma_process_wr_wait_list(con);
@@ -1680,7 +1680,7 @@ static int create_con(struct rtrs_srv_sess *sess,
 		 */
 	}
 	cq_num = max_send_wr + max_recv_wr;
-	atomic_set(&con->sq_wr_avail, max_send_wr);
+	atomic_set(&con->c.sq_wr_avail, max_send_wr);
 	cq_vector = rtrs_srv_get_next_cq_vector(sess);
 
 	/* TODO: SOFTIRQ can be faster, but be careful with softirq context */

drivers/infiniband/ulp/rtrs/rtrs-srv.h

@@ -42,7 +42,6 @@ struct rtrs_srv_stats {
 
 struct rtrs_srv_con {
 	struct rtrs_con		c;
-	atomic_t		sq_wr_avail;
 	struct list_head	rsp_wr_wait_list;
 	spinlock_t		rsp_wr_wait_lock;
 };

drivers/infiniband/ulp/rtrs/rtrs.c

@@ -191,6 +191,7 @@ static int rtrs_post_rdma_write_imm_empty(struct rtrs_con *con,
 	struct rtrs_sess *sess = con->sess;
 	enum ib_send_flags sflags;
 
+	atomic_dec_if_positive(&con->sq_wr_avail);
 	sflags = (atomic_inc_return(&con->wr_cnt) % sess->signal_interval) ?
 		0 : IB_SEND_SIGNALED;