net/mlx5e: Don't wait for SQ completions on close

Instead of asking the firmware to flush the SQ (Send Queue) via
asynchronous completions when moved to error, we handle SQ flush
manually (mlx5e_free_tx_descs) same as we did when SQ flush got
timed out or on tx_timeout.

This will reduce SQs flush time and speedup interface down procedure.

Moved mlx5e_free_tx_descs to the end of en_tx.c for tx
critical code locality.

Fixes: 29429f3300a3 ('net/mlx5e: Timeout if SQ doesn't flush during close')
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 26a7ec7..bf722aa 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -369,9 +369,8 @@ struct mlx5e_sq_dma {
 };
 
 enum {
-       MLX5E_SQ_STATE_WAKE_TXQ_ENABLE,
+       MLX5E_SQ_STATE_FLUSH,
        MLX5E_SQ_STATE_BF_ENABLE,
-       MLX5E_SQ_STATE_TX_TIMEOUT,
 };
 
 struct mlx5e_ico_wqe_info {

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index e259eaa..297781a 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -39,13 +39,6 @@
 #include "eswitch.h"
 #include "vxlan.h"
 
-enum {
-       MLX5_EN_QP_FLUSH_TIMEOUT_MS     = 5000,
-       MLX5_EN_QP_FLUSH_MSLEEP_QUANT   = 20,
-       MLX5_EN_QP_FLUSH_MAX_ITER       = MLX5_EN_QP_FLUSH_TIMEOUT_MS /
-                                         MLX5_EN_QP_FLUSH_MSLEEP_QUANT,
-};
-
 struct mlx5e_rq_param {
        u32                     rqc[MLX5_ST_SZ_DW(rqc)];
        struct mlx5_wq_param    wq;
@@ -827,7 +820,6 @@ static int mlx5e_open_sq(struct mlx5e_channel *c,
                goto err_disable_sq;
 
        if (sq->txq) {
-               set_bit(MLX5E_SQ_STATE_WAKE_TXQ_ENABLE, &sq->state);
                netdev_tx_reset_queue(sq->txq);
                netif_tx_start_queue(sq->txq);
        }
@@ -851,38 +843,20 @@ static inline void netif_tx_disable_queue(struct netdev_queue *txq)
 
 static void mlx5e_close_sq(struct mlx5e_sq *sq)
 {
-       int tout = 0;
-       int err;
+       set_bit(MLX5E_SQ_STATE_FLUSH, &sq->state);
+       /* prevent netif_tx_wake_queue */
+       napi_synchronize(&sq->channel->napi);
 
        if (sq->txq) {
-               clear_bit(MLX5E_SQ_STATE_WAKE_TXQ_ENABLE, &sq->state);
-               /* prevent netif_tx_wake_queue */
-               napi_synchronize(&sq->channel->napi);
                netif_tx_disable_queue(sq->txq);
 
-               /* ensure hw is notified of all pending wqes */
+               /* last doorbell out, godspeed .. */
                if (mlx5e_sq_has_room_for(sq, 1))
                        mlx5e_send_nop(sq, true);
-
-               err = mlx5e_modify_sq(sq, MLX5_SQC_STATE_RDY,
-                                     MLX5_SQC_STATE_ERR, false, 0);
-               if (err)
-                       set_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state);
        }
 
-       /* wait till sq is empty, unless a TX timeout occurred on this SQ */
-       while (sq->cc != sq->pc &&
-              !test_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state)) {
-               msleep(MLX5_EN_QP_FLUSH_MSLEEP_QUANT);
-               if (tout++ > MLX5_EN_QP_FLUSH_MAX_ITER)
-                       set_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state);
-       }
-
-       /* avoid destroying sq before mlx5e_poll_tx_cq() is done with it */
-       napi_synchronize(&sq->channel->napi);
-
-       mlx5e_free_tx_descs(sq);
        mlx5e_disable_sq(sq);
+       mlx5e_free_tx_descs(sq);
        mlx5e_destroy_sq(sq);
 }
 
@@ -2802,7 +2776,7 @@ static void mlx5e_tx_timeout(struct net_device *dev)
                if (!netif_xmit_stopped(netdev_get_tx_queue(dev, i)))
                        continue;
                sched_work = true;
-               set_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state);
+               set_bit(MLX5E_SQ_STATE_FLUSH, &sq->state);
                netdev_err(dev, "TX timeout on queue: %d, SQ: 0x%x, CQ: 0x%x, SQ Cons: 0x%x SQ Prod: 0x%x\n",
                           i, sq->sqn, sq->cq.mcq.cqn, sq->cc, sq->pc);
        }

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
index e073bf5..5f209ad 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -394,35 +394,6 @@ netdev_tx_t mlx5e_xmit(struct sk_buff *skb, struct net_device *dev)
        return mlx5e_sq_xmit(sq, skb);
 }
 
-void mlx5e_free_tx_descs(struct mlx5e_sq *sq)
-{
-       struct mlx5e_tx_wqe_info *wi;
-       struct sk_buff *skb;
-       u16 ci;
-       int i;
-
-       while (sq->cc != sq->pc) {
-               ci = sq->cc & sq->wq.sz_m1;
-               skb = sq->skb[ci];
-               wi = &sq->wqe_info[ci];
-
-               if (!skb) { /* nop */
-                       sq->cc++;
-                       continue;
-               }
-
-               for (i = 0; i < wi->num_dma; i++) {
-                       struct mlx5e_sq_dma *dma =
-                               mlx5e_dma_get(sq, sq->dma_fifo_cc++);
-
-                       mlx5e_tx_dma_unmap(sq->pdev, dma);
-               }
-
-               dev_kfree_skb_any(skb);
-               sq->cc += wi->num_wqebbs;
-       }
-}
-
 bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget)
 {
        struct mlx5e_sq *sq;
@@ -434,7 +405,7 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget)
 
        sq = container_of(cq, struct mlx5e_sq, cq);
 
-       if (unlikely(test_bit(MLX5E_SQ_STATE_TX_TIMEOUT, &sq->state)))
+       if (unlikely(test_bit(MLX5E_SQ_STATE_FLUSH, &sq->state)))
                return false;
 
        npkts = 0;
@@ -512,11 +483,39 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget)
        netdev_tx_completed_queue(sq->txq, npkts, nbytes);
 
        if (netif_tx_queue_stopped(sq->txq) &&
-           mlx5e_sq_has_room_for(sq, MLX5E_SQ_STOP_ROOM) &&
-           likely(test_bit(MLX5E_SQ_STATE_WAKE_TXQ_ENABLE, &sq->state))) {
-                               netif_tx_wake_queue(sq->txq);
-                               sq->stats.wake++;
+           mlx5e_sq_has_room_for(sq, MLX5E_SQ_STOP_ROOM)) {
+               netif_tx_wake_queue(sq->txq);
+               sq->stats.wake++;
        }
 
        return (i == MLX5E_TX_CQ_POLL_BUDGET);
 }
+
+void mlx5e_free_tx_descs(struct mlx5e_sq *sq)
+{
+       struct mlx5e_tx_wqe_info *wi;
+       struct sk_buff *skb;
+       u16 ci;
+       int i;
+
+       while (sq->cc != sq->pc) {
+               ci = sq->cc & sq->wq.sz_m1;
+               skb = sq->skb[ci];
+               wi = &sq->wqe_info[ci];
+
+               if (!skb) { /* nop */
+                       sq->cc++;
+                       continue;
+               }
+
+               for (i = 0; i < wi->num_dma; i++) {
+                       struct mlx5e_sq_dma *dma =
+                               mlx5e_dma_get(sq, sq->dma_fifo_cc++);
+
+                       mlx5e_tx_dma_unmap(sq->pdev, dma);
+               }
+
+               dev_kfree_skb_any(skb);
+               sq->cc += wi->num_wqebbs;
+       }
+}

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
index 64ae2e8..9bf33bb 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
@@ -51,16 +51,18 @@ struct mlx5_cqe64 *mlx5e_get_cqe(struct mlx5e_cq *cq)
 
 static void mlx5e_poll_ico_cq(struct mlx5e_cq *cq)
 {
+       struct mlx5e_sq *sq = container_of(cq, struct mlx5e_sq, cq);
        struct mlx5_wq_cyc *wq;
        struct mlx5_cqe64 *cqe;
-       struct mlx5e_sq *sq;
        u16 sqcc;
 
+       if (unlikely(test_bit(MLX5E_SQ_STATE_FLUSH, &sq->state)))
+               return;
+
        cqe = mlx5e_get_cqe(cq);
        if (likely(!cqe))
                return;
 
-       sq = container_of(cq, struct mlx5e_sq, cq);
        wq = &sq->wq;
 
        /* sq->cc must be updated only after mlx5_cqwq_update_db_record(),