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Date: Wed, 19 Aug 2009 16:53:09 -0700
From: Ron Mercer <ron.mercer@...gic.com>
To: davem@...emloft.net
Cc: netdev@...r.kernel.org, ron.mercer@...gic.com
Subject: [net-next PATCH 1/3] qlge: Move TX completion processing to send path.
Turn off interrupt generation for outbound completions. Handle them in
the send path. Use a timer as a backup that is protected by the
txq->xmit_lock.
Signed-off-by: Ron Mercer <ron.mercer@...gic.com>
---
drivers/net/qlge/qlge.h | 5 ++-
drivers/net/qlge/qlge_main.c | 60 ++++++++++++++++++++++++++++++++++++++---
2 files changed, 58 insertions(+), 7 deletions(-)
diff --git a/drivers/net/qlge/qlge.h b/drivers/net/qlge/qlge.h
index 6ed5317..94dfba4 100644
--- a/drivers/net/qlge/qlge.h
+++ b/drivers/net/qlge/qlge.h
@@ -1205,6 +1205,7 @@ struct bq_desc {
};
#define QL_TXQ_IDX(qdev, skb) (smp_processor_id()%(qdev->tx_ring_count))
+#define TXQ_CLEAN_TIME (HZ/4)
struct tx_ring {
/*
@@ -1224,11 +1225,11 @@ struct tx_ring {
u8 wq_id; /* queue id for this entry */
u8 reserved1[3];
struct tx_ring_desc *q; /* descriptor list for the queue */
- spinlock_t lock;
atomic_t tx_count; /* counts down for every outstanding IO */
atomic_t queue_stopped; /* Turns queue off when full. */
- struct delayed_work tx_work;
+ struct netdev_queue *txq;
struct ql_adapter *qdev;
+ struct timer_list txq_clean_timer;
};
/*
diff --git a/drivers/net/qlge/qlge_main.c b/drivers/net/qlge/qlge_main.c
index 3a271af..c964066 100644
--- a/drivers/net/qlge/qlge_main.c
+++ b/drivers/net/qlge/qlge_main.c
@@ -1797,22 +1797,43 @@ static int ql_clean_outbound_rx_ring(struct rx_ring *rx_ring)
ql_update_cq(rx_ring);
prod = ql_read_sh_reg(rx_ring->prod_idx_sh_reg);
}
+ if (!count)
+ return count;
ql_write_cq_idx(rx_ring);
tx_ring = &qdev->tx_ring[net_rsp->txq_idx];
- if (__netif_subqueue_stopped(qdev->ndev, tx_ring->wq_id) &&
- net_rsp != NULL) {
+ if (netif_tx_queue_stopped(tx_ring->txq)) {
if (atomic_read(&tx_ring->queue_stopped) &&
(atomic_read(&tx_ring->tx_count) > (tx_ring->wq_len / 4)))
/*
* The queue got stopped because the tx_ring was full.
* Wake it up, because it's now at least 25% empty.
*/
- netif_wake_subqueue(qdev->ndev, tx_ring->wq_id);
+ if (netif_running(qdev->ndev)) {
+ netif_tx_wake_queue(tx_ring->txq);
+ atomic_dec(&tx_ring->queue_stopped);
+ }
}
return count;
}
+/* When the lock is free we periodically check for
+ * unhandled completions.
+ */
+static void ql_txq_clean_timer(unsigned long data)
+{
+ struct tx_ring *tx_ring = (struct tx_ring *)data;
+ struct ql_adapter *qdev = tx_ring->qdev;
+ struct rx_ring *rx_ring = &qdev->rx_ring[tx_ring->cq_id];
+
+ if (__netif_tx_trylock(tx_ring->txq)) {
+ ql_clean_outbound_rx_ring(rx_ring);
+ __netif_tx_unlock(tx_ring->txq);
+ }
+ mod_timer(&tx_ring->txq_clean_timer, jiffies + TXQ_CLEAN_TIME);
+
+}
+
static int ql_clean_inbound_rx_ring(struct rx_ring *rx_ring, int budget)
{
struct ql_adapter *qdev = rx_ring->qdev;
@@ -2039,6 +2060,8 @@ static irqreturn_t qlge_isr(int irq, void *dev_id)
rx_ring = &qdev->rx_ring[i];
if (ql_read_sh_reg(rx_ring->prod_idx_sh_reg) !=
rx_ring->cnsmr_idx) {
+ if (rx_ring->type == TX_Q)
+ continue;
QPRINTK(qdev, INTR, INFO,
"Waking handler for rx_ring[%d].\n", i);
ql_disable_completion_interrupt(qdev,
@@ -2146,11 +2169,17 @@ static int qlge_send(struct sk_buff *skb, struct net_device *ndev)
if (skb_padto(skb, ETH_ZLEN))
return NETDEV_TX_OK;
+ /* If there is at least 16 entries to clean then
+ * go do it.
+ */
+ if (tx_ring->wq_len - atomic_read(&tx_ring->tx_count) > 16)
+ ql_clean_outbound_rx_ring(&qdev->rx_ring[tx_ring->cq_id]);
+
if (unlikely(atomic_read(&tx_ring->tx_count) < 2)) {
QPRINTK(qdev, TX_QUEUED, INFO,
"%s: shutting down tx queue %d du to lack of resources.\n",
__func__, tx_ring_idx);
- netif_stop_subqueue(ndev, tx_ring->wq_id);
+ netif_tx_stop_queue(tx_ring->txq);
atomic_inc(&tx_ring->queue_stopped);
return NETDEV_TX_BUSY;
}
@@ -2167,6 +2196,8 @@ static int qlge_send(struct sk_buff *skb, struct net_device *ndev)
tx_ring_desc->skb = skb;
mac_iocb_ptr->frame_len = cpu_to_le16((u16) skb->len);
+ /* Disable completion interrupt for this packet. */
+ mac_iocb_ptr->flags1 |= OB_MAC_IOCB_REQ_I;
if (qdev->vlgrp && vlan_tx_tag_present(skb)) {
QPRINTK(qdev, TX_QUEUED, DEBUG, "Adding a vlan tag %d.\n",
@@ -2192,13 +2223,20 @@ static int qlge_send(struct sk_buff *skb, struct net_device *ndev)
tx_ring->prod_idx++;
if (tx_ring->prod_idx == tx_ring->wq_len)
tx_ring->prod_idx = 0;
+ atomic_dec(&tx_ring->tx_count);
wmb();
+ /* Run the destructor before telling the DMA engine about
+ * the packet to make sure it doesn't complete and get
+ * freed prematurely.
+ */
+ if (likely(!skb_shared(skb)))
+ skb_orphan(skb);
+
ql_write_db_reg(tx_ring->prod_idx, tx_ring->prod_idx_db_reg);
QPRINTK(qdev, TX_QUEUED, DEBUG, "tx queued, slot %d, len %d\n",
tx_ring->prod_idx, skb->len);
- atomic_dec(&tx_ring->tx_count);
return NETDEV_TX_OK;
}
@@ -2783,6 +2821,8 @@ static int ql_start_tx_ring(struct ql_adapter *qdev, struct tx_ring *tx_ring)
*/
tx_ring->cnsmr_idx_sh_reg = shadow_reg;
tx_ring->cnsmr_idx_sh_reg_dma = shadow_reg_dma;
+ *tx_ring->cnsmr_idx_sh_reg = 0;
+ tx_ring->txq = netdev_get_tx_queue(qdev->ndev, tx_ring->wq_id);
wqicb->len = cpu_to_le16(tx_ring->wq_len | Q_LEN_V | Q_LEN_CPP_CONT);
wqicb->flags = cpu_to_le16(Q_FLAGS_LC |
@@ -2802,6 +2842,7 @@ static int ql_start_tx_ring(struct ql_adapter *qdev, struct tx_ring *tx_ring)
return err;
}
QPRINTK(qdev, IFUP, DEBUG, "Successfully loaded WQICB.\n");
+ mod_timer(&tx_ring->txq_clean_timer, jiffies + TXQ_CLEAN_TIME);
return err;
}
@@ -3362,6 +3403,12 @@ static int ql_adapter_down(struct ql_adapter *qdev)
}
}
+ /* Delete the timers used for cleaning up
+ * TX completions.
+ */
+ for (i = 0; i < qdev->tx_ring_count; i++)
+ del_timer_sync(&qdev->tx_ring[i].txq_clean_timer);
+
clear_bit(QL_ADAPTER_UP, &qdev->flags);
ql_disable_interrupts(qdev);
@@ -3501,6 +3548,9 @@ static int ql_configure_rings(struct ql_adapter *qdev)
* immediately after the default Q ID, which is zero.
*/
tx_ring->cq_id = i + 1;
+ init_timer(&tx_ring->txq_clean_timer);
+ tx_ring->txq_clean_timer.data = (unsigned long)tx_ring;
+ tx_ring->txq_clean_timer.function = ql_txq_clean_timer;
}
for (i = 0; i < qdev->rx_ring_count; i++) {
--
1.6.0.2
--
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