From: shemminger@osdl.org Date: Wed, 26 Oct 2005 19:16:10 +0000 (-0700) Subject: [PATCH] sky2: fix NAPI and receive handling X-Git-Tag: v2.6.16-rc1~474^2~22^2~7^2~97^2~4 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bea86103313fae2e29f2d6eb9a4bd7cbeabd4d32;p=linux-2.6 [PATCH] sky2: fix NAPI and receive handling Speed up the receive and interrupt processing and eliminate a couple of race conditions from NAPI code. Signed-off-by: Stephen Hemminger Signed-off-by: Jeff Garzik --- diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c index 92d69fff87..a85a8d1690 100644 --- a/drivers/net/sky2.c +++ b/drivers/net/sky2.c @@ -76,7 +76,7 @@ #define RX_LE_SIZE 256 #define RX_LE_BYTES (RX_LE_SIZE*sizeof(struct sky2_rx_le)) -#define RX_MAX_PENDING (RX_LE_SIZE/2 - 1) +#define RX_MAX_PENDING (RX_LE_SIZE/2 - 2) #define RX_DEF_PENDING 128 #define RX_COPY_THRESHOLD 256 @@ -690,7 +690,7 @@ static inline void sky2_put_idx(struct sky2_hw *hw, unsigned q, setnew: sky2_write16(hw, Y2_QADDR(q, PREF_UNIT_PUT_IDX), idx); } - *last = sky2_read16(hw, Y2_QADDR(q, PREF_UNIT_PUT_IDX)); + *last = idx; } @@ -723,15 +723,6 @@ static inline void sky2_rx_add(struct sky2_port *sky2, struct ring_info *re) le->opcode = OP_PACKET | HW_OWNER; } -/* Tell receiver about new buffers. */ -static inline void rx_set_put(struct net_device *dev) -{ - struct sky2_port *sky2 = netdev_priv(dev); - - if (sky2->rx_last_put != sky2->rx_put) - sky2_put_idx(sky2->hw, rxqaddr[sky2->port], sky2->rx_put, - &sky2->rx_last_put, RX_LE_SIZE); -} /* Tell chip where to start receive checksum. * Actually has two checksums, but set both same to avoid possible byte @@ -1616,6 +1607,10 @@ resubmit: re->skb->ip_summed = CHECKSUM_NONE; sky2_rx_add(sky2, re); + /* Tell receiver about new buffers. */ + sky2_put_idx(sky2->hw, rxqaddr[sky2->port], sky2->rx_put, + &sky2->rx_last_put, RX_LE_SIZE); + return skb; error: @@ -1664,16 +1659,26 @@ static int sky2_poll(struct net_device *dev0, int *budget) hwidx = sky2_read16(hw, STAT_PUT_IDX); BUG_ON(hwidx >= STATUS_RING_SIZE); rmb(); - while (hw->st_idx != hwidx && work_done < to_do) { + + do { struct sky2_status_le *le = hw->st_le + hw->st_idx; struct sky2_port *sky2; struct sk_buff *skb; u32 status; u16 length; - BUG_ON(le->link >= hw->ports); - if (!hw->dev[le->link]) - goto skip; + /* Are we done yet? */ + if (hw->st_idx == hwidx) { + sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ); + hwidx = sky2_read16(hw, STAT_PUT_IDX); + if (hwidx == hw->st_idx) + break; + } + + hw->st_idx = (hw->st_idx + 1) % STATUS_RING_SIZE; + prefetch(&hw->st_le[hw->st_idx]); + + BUG_ON(le->link >= hw->ports || !hw->dev[le->link]); sky2 = netdev_priv(hw->dev[le->link]); status = le32_to_cpu(le->status); @@ -1692,6 +1697,7 @@ static int sky2_poll(struct net_device *dev0, int *budget) } else #endif netif_receive_skb(skb); + ++work_done; break; #ifdef SKY2_VLAN_TAG_USED @@ -1722,22 +1728,11 @@ static int sky2_poll(struct net_device *dev0, int *budget) break; } - skip: - hw->st_idx = (hw->st_idx + 1) % STATUS_RING_SIZE; - if (hw->st_idx == hwidx) { - hwidx = sky2_read16(hw, STAT_PUT_IDX); - rmb(); - } - } + le->opcode = 0; /* paranoia */ + } while (work_done < to_do); mmiowb(); - if (hw->dev[0]) - rx_set_put(hw->dev[0]); - - if (hw->dev[1]) - rx_set_put(hw->dev[1]); - *budget -= work_done; dev0->quota -= work_done; if (work_done < to_do) { @@ -1750,10 +1745,10 @@ static int sky2_poll(struct net_device *dev0, int *budget) sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_START); } + netif_rx_complete(dev0); hw->intr_mask |= Y2_IS_STAT_BMU; sky2_write32(hw, B0_IMSK, hw->intr_mask); sky2_read32(hw, B0_IMSK); - netif_rx_complete(dev0); } return work_done >= to_do; @@ -1880,6 +1875,7 @@ static void sky2_phy_intr(struct sky2_hw *hw, unsigned port) static irqreturn_t sky2_intr(int irq, void *dev_id, struct pt_regs *regs) { struct sky2_hw *hw = dev_id; + struct net_device *dev0 = hw->dev[0]; u32 status; status = sky2_read32(hw, B0_Y2_SP_ISRC2); @@ -1890,12 +1886,13 @@ static irqreturn_t sky2_intr(int irq, void *dev_id, struct pt_regs *regs) sky2_hw_intr(hw); /* Do NAPI for Rx and Tx status */ - if ((status & Y2_IS_STAT_BMU) && netif_rx_schedule_test(hw->dev[0])) { - sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ); - + if (status & Y2_IS_STAT_BMU) { hw->intr_mask &= ~Y2_IS_STAT_BMU; sky2_write32(hw, B0_IMSK, hw->intr_mask); - __netif_rx_schedule(hw->dev[0]); + prefetch(&hw->st_le[hw->st_idx]); + + if (netif_rx_schedule_test(dev0)) + __netif_rx_schedule(dev0); } if (status & Y2_IS_IRQ_PHY1)