svn commit: r308416 - head/sys/dev/mlx5/mlx5_en

[Hans Petter Selasky]

Author: hselasky
Date: Mon Nov  7 11:39:45 2016
New Revision: 308416
URL: https://svnweb.freebsd.org/changeset/base/308416

Log:
  Add timer to watch the RQ when we are out of mbufs.
  
  The firmware/hardware does not generate additional completion
  events unless we post new buffers. Use a timer to try to post
  more buffers in case we are temporarily out of mbufs. Else
  the receive schedule completely stops.
  
  Sponsored by:	Mellanox Technologies
  MFC after:	1 week

Modified:
  head/sys/dev/mlx5/mlx5_en/en.h
  head/sys/dev/mlx5/mlx5_en/mlx5_en_main.c
  head/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c

Modified: head/sys/dev/mlx5/mlx5_en/en.h
==============================================================================
--- head/sys/dev/mlx5/mlx5_en/en.h	Mon Nov  7 11:35:14 2016	(r308415)
+++ head/sys/dev/mlx5/mlx5_en/en.h	Mon Nov  7 11:39:45 2016	(r308416)
@@ -478,6 +478,7 @@ struct mlx5e_rq {
 	struct mlx5_wq_ctrl wq_ctrl;
 	u32	rqn;
 	struct mlx5e_channel *channel;
+	struct callout watchdog;
 } __aligned(MLX5E_CACHELINE_SIZE);
 
 struct mlx5e_sq_mbuf {

Modified: head/sys/dev/mlx5/mlx5_en/mlx5_en_main.c
==============================================================================
--- head/sys/dev/mlx5/mlx5_en/mlx5_en_main.c	Mon Nov  7 11:35:14 2016	(r308415)
+++ head/sys/dev/mlx5/mlx5_en/mlx5_en_main.c	Mon Nov  7 11:39:45 2016	(r308416)
@@ -855,7 +855,13 @@ err_destroy_rq:
 static void
 mlx5e_close_rq(struct mlx5e_rq *rq)
 {
+	mtx_lock(&rq->mtx);
 	rq->enabled = 0;
+	callout_stop(&rq->watchdog);
+	mtx_unlock(&rq->mtx);
+
+	callout_drain(&rq->watchdog);
+
 	mlx5e_modify_rq(rq, MLX5_RQC_STATE_RDY, MLX5_RQC_STATE_ERR);
 }
 
@@ -1439,6 +1445,8 @@ mlx5e_chan_mtx_init(struct mlx5e_channel
 
 	mtx_init(&c->rq.mtx, "mlx5rx", MTX_NETWORK_LOCK, MTX_DEF);
 
+	callout_init_mtx(&c->rq.watchdog, &c->rq.mtx, 0);
+
 	for (tc = 0; tc < c->num_tc; tc++) {
 		struct mlx5e_sq *sq = c->sq + tc;
 

Modified: head/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c
==============================================================================
--- head/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c	Mon Nov  7 11:35:14 2016	(r308415)
+++ head/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c	Mon Nov  7 11:39:45 2016	(r308416)
@@ -82,9 +82,10 @@ mlx5e_post_rx_wqes(struct mlx5e_rq *rq)
 	while (!mlx5_wq_ll_is_full(&rq->wq)) {
 		struct mlx5e_rx_wqe *wqe = mlx5_wq_ll_get_wqe(&rq->wq, rq->wq.head);
 
-		if (unlikely(mlx5e_alloc_rx_wqe(rq, wqe, rq->wq.head)))
+		if (unlikely(mlx5e_alloc_rx_wqe(rq, wqe, rq->wq.head))) {
+			callout_reset_curcpu(&rq->watchdog, 1, (void *)&mlx5e_post_rx_wqes, rq);
 			break;
-
+		}
 		mlx5_wq_ll_push(&rq->wq, be16_to_cpu(wqe->next.next_wqe_index));
 	}