From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH 04/12] sky2: check for more work before leaving NAPI Date: Mon, 09 Jul 2007 15:33:36 -0700 Message-ID: <20070709223453.238106926@linux-foundation.org> References: <20070709223332.966231494@linux-foundation.org> Cc: netdev@vger.kernel.org To: Jeff Garzik Return-path: Received: from smtp2.linux-foundation.org ([207.189.120.14]:47881 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755403AbXGIWgm (ORCPT ); Mon, 9 Jul 2007 18:36:42 -0400 Content-Disposition: inline; filename=sky2-work-check.patch Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org This patch avoids generating another IRQ if more packets arrive while in the NAPI poll routine. Before marking device as finished, it rechecks that the status ring is empty. Signed-off-by: Stephen Hemminger --- a/drivers/net/sky2.c 2007-07-09 15:30:09.000000000 -0700 +++ b/drivers/net/sky2.c 2007-07-09 15:30:10.000000000 -0700 @@ -2477,8 +2477,7 @@ static void sky2_err_intr(struct sky2_hw static int sky2_poll(struct net_device *dev0, int *budget) { struct sky2_hw *hw = ((struct sky2_port *) netdev_priv(dev0))->hw; - int work_limit = min(dev0->quota, *budget); - int work_done = 0; + int work_done; u32 status = sky2_read32(hw, B0_Y2_SP_EISR); if (unlikely(status & Y2_IS_ERROR)) @@ -2490,25 +2489,25 @@ static int sky2_poll(struct net_device * if (status & Y2_IS_IRQ_PHY2) sky2_phy_intr(hw, 1); - work_done = sky2_status_intr(hw, work_limit); - if (work_done < work_limit) { - /* Bug/Errata workaround? - * Need to kick the TX irq moderation timer. - */ - if (sky2_read8(hw, STAT_TX_TIMER_CTRL) == TIM_START) { - sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_STOP); - sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_START); - } - netif_rx_complete(dev0); + work_done = sky2_status_intr(hw, min(dev0->quota, *budget)); + *budget -= work_done; + dev0->quota -= work_done; - /* end of interrupt, re-enables also acts as I/O synchronization */ - sky2_read32(hw, B0_Y2_SP_LISR); - return 0; - } else { - *budget -= work_done; - dev0->quota -= work_done; + /* More work? */ + if (hw->st_idx != sky2_read16(hw, STAT_PUT_IDX)) return 1; + + /* Bug/Errata workaround? + * Need to kick the TX irq moderation timer. + */ + if (sky2_read8(hw, STAT_TX_TIMER_CTRL) == TIM_START) { + sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_STOP); + sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_START); } + netif_rx_complete(dev0); + + sky2_read32(hw, B0_Y2_SP_LISR); + return 0; } static irqreturn_t sky2_intr(int irq, void *dev_id) -- Stephen Hemminger