[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 <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index eea4181..a629706 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -488,7 +488,8 @@
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 @@
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 @@
* 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 @@
*/
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 @@
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 |