bna: Remove tx tasklet
authorJing Huang <huangj@Brocade.COM>
Wed, 4 Apr 2012 05:43:48 +0000 (05:43 +0000)
committerDavid S. Miller <davem@davemloft.net>
Wed, 4 Apr 2012 22:19:18 +0000 (18:19 -0400)
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>
drivers/net/ethernet/brocade/bna/bnad.c
drivers/net/ethernet/brocade/bna/bnad.h

index 032a306c0569c8dc0b4c4a38f04a99320aed2fef..f1103e6f31c1f5dcfb712ecbd02bc376323e0369 100644 (file)
@@ -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)
index ff129aa7cb66b4049494ef14ab488faaeb53499d..cf1d3bad01b646a694885db797f82b1139815911 100644 (file)
@@ -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 */