From 38f3843ed6bdbcff9465386c3539523466880320 Mon Sep 17 00:00:00 2001 From: Michael Chan Date: Mon, 5 Sep 2005 17:53:32 -0700 Subject: [PATCH] [TG3]: Use status tag to check for new events Use the status tag to determine if there are new events in tg3_interrupt_tagged(). We discussed about this a while ago with Grant Grundler and DaveM. This scheme makes it unnecessary to clear the updated bit in the status block when using tagged mode, and only a simple comparison is needed to determine if there are new events. The tp->lock around netif_rx_complete() and tg3_restart_ints() is also removed. It is unnecessary with DaveM's new locking scheme. Signed-off-by: Michael Chan Signed-off-by: David S. Miller --- drivers/net/tg3.c | 32 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 17 deletions(-) diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c index eea418124be..a629706e2b3 100644 --- a/drivers/net/tg3.c +++ b/drivers/net/tg3.c @@ -488,7 +488,8 @@ static void tg3_disable_ints(struct tg3 *tp) static inline void tg3_cond_int(struct tg3 *tp) { - if (tp->hw_status->status & SD_STATUS_UPDATED) + if (!(tp->tg3_flags & TG3_FLAG_TAGGED_STATUS) && + (tp->hw_status->status & SD_STATUS_UPDATED)) tw32(GRC_LOCAL_CTRL, tp->grc_local_ctrl | GRC_LCLCTRL_SETINT); } @@ -3220,18 +3221,17 @@ static int tg3_poll(struct net_device *netdev, int *budget) netdev->quota -= work_done; } - if (tp->tg3_flags & TG3_FLAG_TAGGED_STATUS) + if (tp->tg3_flags & TG3_FLAG_TAGGED_STATUS) { tp->last_tag = sblk->status_tag; - rmb(); - sblk->status &= ~SD_STATUS_UPDATED; + rmb(); + } else + sblk->status &= ~SD_STATUS_UPDATED; /* if no more work, tell net stack and NIC we're done */ done = !tg3_has_work(tp); if (done) { - spin_lock(&tp->lock); netif_rx_complete(netdev); tg3_restart_ints(tp); - spin_unlock(&tp->lock); } return (done ? 0 : 1); @@ -3351,7 +3351,7 @@ static irqreturn_t tg3_interrupt_tagged(int irq, void *dev_id, struct pt_regs *r * Reading the PCI State register will confirm whether the * interrupt is ours and will flush the status block. */ - if ((sblk->status & SD_STATUS_UPDATED) || + if ((sblk->status_tag != tp->last_tag) || !(tr32(TG3PCI_PCISTATE) & PCISTATE_INT_NOT_ACTIVE)) { /* * writing any value to intr-mbox-0 clears PCI INTA# and @@ -3362,20 +3362,17 @@ static irqreturn_t tg3_interrupt_tagged(int irq, void *dev_id, struct pt_regs *r */ tw32_mailbox(MAILBOX_INTERRUPT_0 + TG3_64BIT_REG_LOW, 0x00000001); - tp->last_tag = sblk->status_tag; - rmb(); if (tg3_irq_sync(tp)) goto out; - sblk->status &= ~SD_STATUS_UPDATED; - if (likely(tg3_has_work(tp))) { + if (netif_rx_schedule_prep(dev)) { prefetch(&tp->rx_rcb[tp->rx_rcb_ptr]); - netif_rx_schedule(dev); /* schedule NAPI poll */ - } else { - /* no work, shared interrupt perhaps? re-enable - * interrupts, and flush that PCI write + /* Update last_tag to mark that this status has been + * seen. Because interrupt may be shared, we may be + * racing with tg3_poll(), so only update last_tag + * if tg3_poll() is not scheduled. */ - tw32_mailbox_f(MAILBOX_INTERRUPT_0 + TG3_64BIT_REG_LOW, - tp->last_tag << 24); + tp->last_tag = sblk->status_tag; + __netif_rx_schedule(dev); } } else { /* shared interrupt */ handled = 0; @@ -6238,6 +6235,7 @@ static int tg3_test_interrupt(struct tg3 *tp) if (err) return err; + tp->hw_status->status &= ~SD_STATUS_UPDATED; tg3_enable_ints(tp); tw32_f(HOSTCC_MODE, tp->coalesce_mode | HOSTCC_MODE_ENABLE | -- 2.11.4.GIT