From 6cdfab2868dd593902e2b7db3ba9f49f2cc03e3f Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Sun, 27 Mar 2011 13:37:35 +0200 Subject: [PATCH] e1000: check buffer availability 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 --- hw/e1000.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/hw/e1000.c b/hw/e1000.c index 2a4d5c726c..55daae0eba 100644 --- a/hw/e1000.c +++ b/hw/e1000.c @@ -625,14 +625,6 @@ 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; @@ -651,6 +643,14 @@ 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) { -- 2.11.4.GIT