From 60cba200f11b6f90f35634c5cd608773ae3721b7 Mon Sep 17 00:00:00 2001 From: Jesse Brandeburg Date: Thu, 18 Jan 2007 09:25:23 -0800 Subject: [PATCH] e1000: fix NAPI performance on 4-port adapters This fix attempts to solve a customer (IBM) reported issue with NAPI enabled e1000 having bad performance when transmitting simultaneously on four ports. The issue comes down to an interaction between NAPI, hardware interrupt balancing, and the driver rescheduling poll on the same processor. Try to fix by allowing the driver to re-enable interrupts sooner instead of polling one more time, when there was recently all the work completed in cleanup. Signed-off-by: Jesse Brandeburg Signed-off-by: Auke Kok --- drivers/net/e1000/e1000_main.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c index d408949d61dd..ab1b40f644d7 100644 --- a/drivers/net/e1000/e1000_main.c +++ b/drivers/net/e1000/e1000_main.c @@ -3814,7 +3814,7 @@ e1000_intr_msi(int irq, void *data) for (i = 0; i < E1000_MAX_INTR; i++) if (unlikely(!adapter->clean_rx(adapter, adapter->rx_ring) & - !e1000_clean_tx_irq(adapter, adapter->tx_ring))) + e1000_clean_tx_irq(adapter, adapter->tx_ring))) break; if (likely(adapter->itr_setting & 3)) @@ -3917,7 +3917,7 @@ e1000_intr(int irq, void *data) for (i = 0; i < E1000_MAX_INTR; i++) if (unlikely(!adapter->clean_rx(adapter, adapter->rx_ring) & - !e1000_clean_tx_irq(adapter, adapter->tx_ring))) + e1000_clean_tx_irq(adapter, adapter->tx_ring))) break; if (likely(adapter->itr_setting & 3)) @@ -3967,7 +3967,7 @@ e1000_clean(struct net_device *poll_dev, int *budget) poll_dev->quota -= work_done; /* If no Tx and not enough Rx work done, exit the polling mode */ - if ((!tx_cleaned && (work_done == 0)) || + if ((tx_cleaned && (work_done < work_to_do)) || !netif_running(poll_dev)) { quit_polling: if (likely(adapter->itr_setting & 3)) @@ -3997,7 +3997,7 @@ e1000_clean_tx_irq(struct e1000_adapter *adapter, #ifdef CONFIG_E1000_NAPI unsigned int count = 0; #endif - boolean_t cleaned = FALSE; + boolean_t cleaned = TRUE; unsigned int total_tx_bytes=0, total_tx_packets=0; i = tx_ring->next_to_clean; @@ -4028,7 +4028,10 @@ e1000_clean_tx_irq(struct e1000_adapter *adapter, #ifdef CONFIG_E1000_NAPI #define E1000_TX_WEIGHT 64 /* weight of a sort for tx, to avoid endless transmit cleanup */ - if (count++ == E1000_TX_WEIGHT) break; + if (count++ == E1000_TX_WEIGHT) { + cleaned = FALSE; + break; + } #endif } -- 2.20.1