openkylin
/
qemu
mirror of https://gitee.com/openkylin/qemu.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

tap: drain queue in tap_send() 

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 <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Mark McLoughlin 2009-10-27 18:16:39 +00:00 committed by Anthony Liguori
parent cdd5cc12ba
commit 5819c91806
1 changed files with 16 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
net/tap.c
View File

@ -188,23 +188,26 @@ 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)