Change the refresh_mbuf logic slightly, add an inline

to calculate the outstanding descriptors that need to be
refreshed at any time, and use THAT in rxeof to determine
if refreshing needs to be done. Also change the local_timer
to simply fire off the appropriate interrupt rather than
schedule a tasklet, its simpler.

MFC in two weeks

2 files changed, 30 insertions, 10 deletions

diff --git a/sys/dev/e1000/if_em.c b/sys/dev/e1000/if_em.c
index c119144..6dcd90d 100644
--- a/sys/dev/e1000/if_em.c
+++ b/sys/dev/e1000/if_em.c
@@ -1,6 +1,6 @@
 /******************************************************************************
 
-  Copyright (c) 2001-2010, Intel Corporation 
+  Copyright (c) 2001-2011, Intel Corporation 
   All rights reserved.
   
   Redistribution and use in source and binary forms, with or without 
@@ -93,7 +93,7 @@ int	em_display_debug_stats = 0;
 /*********************************************************************
  *  Driver version:
  *********************************************************************/
-char em_driver_version[] = "7.2.2";
+char em_driver_version[] = "7.2.3";
 
 /*********************************************************************
  *  PCI Device ID Table
@@ -2182,6 +2182,7 @@ em_local_timer(void *arg)
 	struct ifnet	*ifp = adapter->ifp;
 	struct tx_ring	*txr = adapter->tx_rings;
 	struct rx_ring	*rxr = adapter->rx_rings;
+	u32		trigger;
 
 	EM_CORE_LOCK_ASSERT(adapter);
 
@@ -2193,12 +2194,11 @@ em_local_timer(void *arg)
 	    e1000_get_laa_state_82571(&adapter->hw))
 		e1000_rar_set(&adapter->hw, adapter->hw.mac.addr, 0);
 
-	/* trigger tq to refill rx ring queue if it is empty */
-	for (int i = 0; i < adapter->num_queues; i++, rxr++) {
-		if (rxr->next_to_check == rxr->next_to_refresh) {
-			taskqueue_enqueue(rxr->tq, &rxr->rx_task);
-		}
-	}
+	/* Mask to use in the irq trigger */
+	if (adapter->msix_mem)
+		trigger = rxr->ims; /* RX for 82574 */
+	else
+		trigger = E1000_ICS_RXDMT0;
 
 	/* 
 	** Don't do TX watchdog check if we've been paused
@@ -2217,6 +2217,10 @@ em_local_timer(void *arg)
 			goto hung;
 out:
 	callout_reset(&adapter->timer, hz, em_local_timer, adapter);
+#ifndef DEVICE_POLLING
+	/* Trigger an RX interrupt to guarantee mbuf refresh */
+	E1000_WRITE_REG(&adapter->hw, E1000_ICS, trigger);
+#endif
 	return;
 hung:
 	/* Looks like we're hung */
@@ -4327,7 +4331,7 @@ next_desc:
 	}
 
 	/* Catch any remaining refresh work */
-	if (processed != 0 || i == rxr->next_to_refresh)
+	if (e1000_rx_unrefreshed(rxr))
 		em_refresh_mbufs(rxr, i);
 
 	rxr->next_to_check = i;
diff --git a/sys/dev/e1000/if_em.h b/sys/dev/e1000/if_em.h
index d27a53a..e25904e 100644
--- a/sys/dev/e1000/if_em.h
+++ b/sys/dev/e1000/if_em.h
@@ -1,6 +1,6 @@
 /******************************************************************************
 
-  Copyright (c) 2001-2010, Intel Corporation 
+  Copyright (c) 2001-2011, Intel Corporation 
   All rights reserved.
   
   Redistribution and use in source and binary forms, with or without 
@@ -463,6 +463,22 @@ struct em_buffer {
         bus_dmamap_t    map;         /* bus_dma map for packet */
 };
 
+
+/*
+** Find the number of unrefreshed RX descriptors
+*/
+static inline u16
+e1000_rx_unrefreshed(struct rx_ring *rxr)
+{
+	struct adapter	*adapter = rxr->adapter;
+
+	if (rxr->next_to_check > rxr->next_to_refresh)
+		return (rxr->next_to_check - rxr->next_to_refresh - 1);
+	else
+		return ((adapter->num_rx_desc + rxr->next_to_check) -
+		    rxr->next_to_refresh - 1); 
+}
+
 #define	EM_CORE_LOCK_INIT(_sc, _name) \
 	mtx_init(&(_sc)->core_mtx, _name, "EM Core Lock", MTX_DEF)
 #define	EM_TX_LOCK_INIT(_sc, _name) \