bna: Remove tx tasklet

The scheduling of tasklet and keeping the interrupts enabled makes interrupt
reduntant. 20% of the Tx interrupts have nothing left to process or could not
process as Tx tasklet was running.

Signed-off-by: Jing Huang <huangj@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 3 insertions, 71 deletions

diff --git a/drivers/net/ethernet/brocade/bna/bnad.c b/drivers/net/ethernet/brocade/bna/bnad.c
index 032a306c0569..f1103e6f31c1 100644
--- a/drivers/net/ethernet/brocade/bna/bnad.c
+++ b/drivers/net/ethernet/brocade/bna/bnad.c
@@ -185,7 +185,6 @@ bnad_free_all_txbufs(struct bnad *bnad,
  * bnad_free_txbufs : Frees the Tx bufs on Tx completion
  * Can be called in a) Interrupt context
  *                  b) Sending context
- *                  c) Tasklet context
  */
 static u32
 bnad_free_txbufs(struct bnad *bnad,
@@ -197,13 +196,7 @@ bnad_free_txbufs(struct bnad *bnad,
         struct bnad_skb_unmap *unmap_array;
         struct sk_buff          *skb;
 
-        /*
-         * Just return if TX is stopped. This check is useful
-         * when bnad_free_txbufs() runs out of a tasklet scheduled
-         * before bnad_cb_tx_cleanup() cleared BNAD_TXQ_TX_STARTED bit
-         * but this routine runs actually after the cleanup has been
-         * executed.
-         */
+        /* Just return if TX is stopped */
         if (!test_bit(BNAD_TXQ_TX_STARTED, &tcb->flags))
                 return 0;
 
@@ -242,55 +235,6 @@ bnad_free_txbufs(struct bnad *bnad,
         return sent_packets;
 }
 
-/* Tx Free Tasklet function */
-/* Frees for all the tcb's in all the Tx's */
-/*
- * Scheduled from sending context, so that
- * the fat Tx lock is not held for too long
- * in the sending context.
- */
-static void
-bnad_tx_free_tasklet(unsigned long bnad_ptr)
-{
-        struct bnad *bnad = (struct bnad *)bnad_ptr;
-        struct bna_tcb *tcb;
-        u32             acked = 0;
-        int                     i, j;
-
-        for (i = 0; i < bnad->num_tx; i++) {
-                for (j = 0; j < bnad->num_txq_per_tx; j++) {
-                        tcb = bnad->tx_info[i].tcb[j];
-                        if (!tcb)
-                                continue;
-                        if (((u16) (*tcb->hw_consumer_index) !=
-                                tcb->consumer_index) &&
-                                (!test_and_set_bit(BNAD_TXQ_FREE_SENT,
-                                                  &tcb->flags))) {
-                                acked = bnad_free_txbufs(bnad, tcb);
-                                if (likely(test_bit(BNAD_TXQ_TX_STARTED,
-                                        &tcb->flags)))
-                                        bna_ib_ack(tcb->i_dbell, acked);
-                                smp_mb__before_clear_bit();
-                                clear_bit(BNAD_TXQ_FREE_SENT, &tcb->flags);
-                        }
-                        if (unlikely(!test_bit(BNAD_TXQ_TX_STARTED,
-                                                &tcb->flags)))
-                                continue;
-                        if (netif_queue_stopped(bnad->netdev)) {
-                                if (acked && netif_carrier_ok(bnad->netdev) &&
-                                        BNA_QE_FREE_CNT(tcb, tcb->q_depth) >=
-                                                BNAD_NETIF_WAKE_THRESHOLD) {
-                                        netif_wake_queue(bnad->netdev);
-                                        /* TODO */
-                                        /* Counters for individual TxQs? */
-                                        BNAD_UPDATE_CTR(bnad,
-                                                netif_queue_wakeup);
-                                }
-                        }
-                }
-        }
-}
-
 static u32
 bnad_tx(struct bnad *bnad, struct bna_tcb *tcb)
 {
@@ -1789,9 +1733,6 @@ bnad_cleanup_tx(struct bnad *bnad, u32 tx_id)
                 bnad_tx_msix_unregister(bnad, tx_info,
                         bnad->num_txq_per_tx);
 
-        if (0 == tx_id)
-                tasklet_kill(&bnad->tx_free_tasklet);
-
         spin_lock_irqsave(&bnad->bna_lock, flags);
         bna_tx_destroy(tx_info->tx);
         spin_unlock_irqrestore(&bnad->bna_lock, flags);
@@ -2871,9 +2812,6 @@ bnad_start_xmit(struct sk_buff *skb, struct net_device *netdev)
         bna_txq_prod_indx_doorbell(tcb);
         smp_mb();
 
-        if ((u16) (*tcb->hw_consumer_index) != tcb->consumer_index)
-                tasklet_schedule(&bnad->tx_free_tasklet);
-
         return NETDEV_TX_OK;
 }
 
@@ -3155,9 +3093,8 @@ bnad_netdev_init(struct bnad *bnad, bool using_dac)
 /*
  * 1. Initialize the bnad structure
  * 2. Setup netdev pointer in pci_dev
- * 3. Initialze Tx free tasklet
- * 4. Initialize no. of TxQ & CQs & MSIX vectors
- * 5. Initialize work queue.
+ * 3. Initialize no. of TxQ & CQs & MSIX vectors
+ * 4. Initialize work queue.
  */
 static int
 bnad_init(struct bnad *bnad,
@@ -3200,9 +3137,6 @@ bnad_init(struct bnad *bnad,
         bnad->tx_coalescing_timeo = BFI_TX_COALESCING_TIMEO;
         bnad->rx_coalescing_timeo = BFI_RX_COALESCING_TIMEO;
 
-        tasklet_init(&bnad->tx_free_tasklet, bnad_tx_free_tasklet,
-                     (unsigned long)bnad);
-
         sprintf(bnad->wq_name, "%s_wq_%d", BNAD_NAME, bnad->id);
         bnad->work_q = create_singlethread_workqueue(bnad->wq_name);
 
@@ -3345,7 +3279,6 @@ bnad_pci_probe(struct pci_dev *pdev,
         /*
          * Initialize bnad structure
          * Setup relation between pci_dev & netdev
-         * Init Tx free tasklet
          */
         err = bnad_init(bnad, pdev, netdev);
         if (err)
diff --git a/drivers/net/ethernet/brocade/bna/bnad.h b/drivers/net/ethernet/brocade/bna/bnad.h
index ff129aa7cb66..cf1d3bad01b6 100644
--- a/drivers/net/ethernet/brocade/bna/bnad.h
+++ b/drivers/net/ethernet/brocade/bna/bnad.h
@@ -320,7 +320,6 @@ struct bnad {
         /* Burnt in MAC address */
         mac_t                   perm_addr;
 
-        struct tasklet_struct   tx_free_tasklet;
         struct workqueue_struct *work_q;
 
         /* Statistics */