mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

net: Fix send queue ordering

Browse Source 
Ensure that packets enqueued for delayed delivery are dequeued in FIFO
order. At least one simplistic guest TCP/IP stack became unhappy due to
sporadically reordered packet streams.

At this chance, switch the send queue implementation to TAILQ.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Jan Kiszka 2009-08-26 12:47:04 +02:00 committed by Anthony Liguori
parent 4e2f73ce3d
commit 9da4318706
2 changed files with 15 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
net.c
View File

@ -436,33 +436,28 @@ qemu_deliver_packet(VLANClientState *sender, const uint8_t *buf, int size)
void qemu_purge_queued_packets(VLANClientState *vc)
{
VLANPacket **pp = &vc->vlan->send_queue;
while (*pp != NULL) {
VLANPacket *packet = *pp;
VLANPacket *packet, *next;
TAILQ_FOREACH_SAFE(packet, &vc->vlan->send_queue, entry, next) {
if (packet->sender == vc) {
*pp = packet->next;
TAILQ_REMOVE(&vc->vlan->send_queue, packet, entry);
qemu_free(packet);
} else {
pp = &packet->next;
}
}
}
void qemu_flush_queued_packets(VLANClientState *vc)
{
VLANPacket *packet;
while ((packet = vc->vlan->send_queue) != NULL) {
while (!TAILQ_EMPTY(&vc->vlan->send_queue)) {
VLANPacket *packet;
int ret;
vc->vlan->send_queue = packet->next;
packet = TAILQ_FIRST(&vc->vlan->send_queue);
TAILQ_REMOVE(&vc->vlan->send_queue, packet, entry);
ret = qemu_deliver_packet(packet->sender, packet->data, packet->size);
if (ret == 0 && packet->sent_cb != NULL) {
packet->next = vc->vlan->send_queue;
vc->vlan->send_queue = packet;
TAILQ_INSERT_HEAD(&vc->vlan->send_queue, packet, entry);
break;
}
@ -480,12 +475,12 @@ static void qemu_enqueue_packet(VLANClientState *sender,
VLANPacket *packet;
packet = qemu_malloc(sizeof(VLANPacket) + size);
packet->next = sender->vlan->send_queue;
packet->sender = sender;
packet->size = size;
packet->sent_cb = sent_cb;
memcpy(packet->data, buf, size);
sender->vlan->send_queue = packet;
TAILQ_INSERT_TAIL(&sender->vlan->send_queue, packet, entry);
}
ssize_t qemu_send_packet_async(VLANClientState *sender,
@ -597,7 +592,6 @@ static ssize_t qemu_enqueue_packet_iov(VLANClientState *sender,
max_len = calc_iov_length(iov, iovcnt);
packet = qemu_malloc(sizeof(VLANPacket) + max_len);
packet->next = sender->vlan->send_queue;
packet->sender = sender;
packet->sent_cb = sent_cb;
packet->size = 0;
@ -609,7 +603,7 @@ static ssize_t qemu_enqueue_packet_iov(VLANClientState *sender,
packet->size += len;
}
sender->vlan->send_queue = packet;
TAILQ_INSERT_TAIL(&sender->vlan->send_queue, packet, entry);
return packet->size;
}
@ -2330,6 +2324,7 @@ VLANState *qemu_find_vlan(int id, int allocate)
}
vlan = qemu_mallocz(sizeof(VLANState));
vlan->id = id;
TAILQ_INIT(&vlan->send_queue);
vlan->next = NULL;
pvlan = &first_vlan;
while (*pvlan != NULL)

5
net.h
View File

@ -1,6 +1,7 @@
#ifndef QEMU_NET_H
#define QEMU_NET_H
#include "sys-queue.h"
#include "qemu-common.h"
/* VLANs support */
@ -35,7 +36,7 @@ typedef struct VLANPacket VLANPacket;
typedef void (NetPacketSent) (VLANClientState *, ssize_t);
struct VLANPacket {
struct VLANPacket *next;
TAILQ_ENTRY(VLANPacket) entry;
VLANClientState *sender;
int size;
NetPacketSent *sent_cb;
@ -47,7 +48,7 @@ struct VLANState {
VLANClientState *first_client;
struct VLANState *next;
unsigned int nb_guest_devs, nb_host_devs;
VLANPacket *send_queue;
TAILQ_HEAD(send_queue, VLANPacket) send_queue;
int delivering;
};