[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH 5/5] tap: drain queue in tap_send()
From: |
Mark McLoughlin |
Subject: |
[Qemu-devel] [PATCH 5/5] tap: drain queue in tap_send() |
Date: |
Tue, 27 Oct 2009 18:16:39 +0000 |
Okay, let's try re-enabling the drain-entire-queue behaviour, with a
difference - before each subsequent packet, use qemu_can_send_packet()
to check that we can send it. This is similar to how we check before
polling the tap fd and avoids having to drop a packet if the receiver
cannot handle it.
This patch should be a performance improvement since we no longer have
to go through the mainloop for each packet.
Signed-off-by: Mark McLoughlin <address@hidden>
---
net/tap.c | 33 ++++++++++++++++++---------------
1 files changed, 18 insertions(+), 15 deletions(-)
diff --git a/net/tap.c b/net/tap.c
index f32226b..5272d7d 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -187,23 +187,26 @@ static void tap_send_completed(VLANClientState *vc,
ssize_t len)
static void tap_send(void *opaque)
{
TAPState *s = opaque;
- uint8_t *buf = s->buf;
int size;
- size = tap_read_packet(s->fd, s->buf, sizeof(s->buf));
- if (size <= 0) {
- return;
- }
+ do {
+ uint8_t *buf = s->buf;
- if (s->has_vnet_hdr && !s->using_vnet_hdr) {
- buf += sizeof(struct virtio_net_hdr);
- size -= sizeof(struct virtio_net_hdr);
- }
+ size = tap_read_packet(s->fd, s->buf, sizeof(s->buf));
+ if (size <= 0) {
+ break;
+ }
- size = qemu_send_packet_async(s->vc, buf, size, tap_send_completed);
- if (size == 0) {
- tap_read_poll(s, 0);
- }
+ if (s->has_vnet_hdr && !s->using_vnet_hdr) {
+ buf += sizeof(struct virtio_net_hdr);
+ size -= sizeof(struct virtio_net_hdr);
+ }
+
+ size = qemu_send_packet_async(s->vc, buf, size, tap_send_completed);
+ if (size == 0) {
+ tap_read_poll(s, 0);
+ }
+ } while (size > 0 && qemu_can_send_packet(s->vc));
}
int tap_has_ufo(VLANClientState *vc)
--
1.6.2.5