Patchwork e1000: check buffer availability

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Submitter Michael S. Tsirkin
Date March 27, 2011, 3:01 p.m.
Message ID <20110327150156.GA7975@redhat.com>
Download mbox | patch
Permalink /patch/88510/
State New
Headers show

Comments

Michael S. Tsirkin - March 27, 2011, 3:01 p.m.
Reduce spurious packet drops on RX ring empty
by verifying that we have at least 1 buffer
ahead of the time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/e1000.c |   16 ++++++++--------
 1 files changed, 8 insertions(+), 8 deletions(-)
Juan Quintela - March 28, 2011, 10:50 a.m.
"Michael S. Tsirkin" <mst@redhat.com> wrote:
> Reduce spurious packet drops on RX ring empty
> by verifying that we have at least 1 buffer
> ahead of the time.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Reviewed-by: Juan Quintela <quintela@redhat.com>
Kevin Wolf - March 28, 2011, 11:37 a.m.
Am 27.03.2011 17:01, schrieb Michael S. Tsirkin:
> Reduce spurious packet drops on RX ring empty
> by verifying that we have at least 1 buffer
> ahead of the time.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Acked-by: Kevin Wolf <kwolf@redhat.com>

Patch

diff --git a/hw/e1000.c b/hw/e1000.c
index 0a4574c..380d6fe 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -623,14 +623,6 @@  e1000_set_link_status(VLANClientState *nc)
         set_ics(s, 0, E1000_ICR_LSC);
 }
 
-static int
-e1000_can_receive(VLANClientState *nc)
-{
-    E1000State *s = DO_UPCAST(NICState, nc, nc)->opaque;
-
-    return (s->mac_reg[RCTL] & E1000_RCTL_EN);
-}
-
 static bool e1000_has_rxbufs(E1000State *s, size_t total_size)
 {
     int bufs;
@@ -649,6 +641,14 @@  static bool e1000_has_rxbufs(E1000State *s, size_t total_size)
     return total_size <= bufs * s->rxbuf_size;
 }
 
+static int
+e1000_can_receive(VLANClientState *nc)
+{
+    E1000State *s = DO_UPCAST(NICState, nc, nc)->opaque;
+
+    return (s->mac_reg[RCTL] & E1000_RCTL_EN) && e1000_has_rxbufs(s, 1);
+}
+
 static ssize_t
 e1000_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
 {