Allow reconnecting on failure when both RTE_VHOST_USER_RECONNECT and
RTE_VHOST_USER_CLIENT flags are set.
Reconnecting means two things here:
- when DPDK app starts first and QEMU (as the server) is not started,
without reconnecting, DPDK app would simply fail on vhost-user
registration.
- when QEMU reboots, without reconnecting, you can't re-establish the
connection without restarting DPDK app.
This patch make it work well for both above cases. It simply creates
a new thread, and keep trying calling "connect()", until it succeeds.
Signed-off-by: Yuanhan Liu <yuanhan.liu at linux.intel.com>
---
lib/librte_vhost/rte_virtio_net.h | 1 +
lib/librte_vhost/vhost_user/vhost-net-user.c | 63 +++++++++++++++++++++++++---
2 files changed, 59 insertions(+), 5 deletions(-)
diff --git a/lib/librte_vhost/rte_virtio_net.h
b/lib/librte_vhost/rte_virtio_net.h
index c84e7ab..f354d52 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -52,6 +52,7 @@
#include <rte_ether.h>
#define RTE_VHOST_USER_CLIENT (1ULL << 0)
+#define RTE_VHOST_USER_RECONNECT (1ULL << 1)
struct rte_mbuf;
diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.c
b/lib/librte_vhost/vhost_user/vhost-net-user.c
index aa98717..07bce6e 100644
--- a/lib/librte_vhost/vhost_user/vhost-net-user.c
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.c
@@ -59,6 +59,7 @@ struct vhost_user_socket {
char *path;
int listenfd;
int is_server;
+ int reconnect;
};
struct vhost_user_connection {
@@ -78,6 +79,7 @@ struct vhost_user {
static void vhost_user_server_new_connection(int fd, void *data, int *remove);
static void vhost_user_msg_handler(int fd, void *dat, int *remove);
+static int vhost_user_create_client(struct vhost_user_socket *vsocket);
static struct vhost_user vhost_user = {
.fdset = {
@@ -304,6 +306,8 @@ vhost_user_msg_handler(int connfd, void *dat, int *remove)
vid = conn->vid;
ret = read_vhost_message(connfd, &msg);
if (ret <= 0 || msg.request >= VHOST_USER_MAX) {
+ struct vhost_user_socket *vsocket = conn->vsocket;
+
if (ret < 0)
RTE_LOG(ERR, VHOST_CONFIG,
"vhost read message failed\n");
@@ -319,6 +323,9 @@ vhost_user_msg_handler(int connfd, void *dat, int *remove)
free(conn);
vhost_destroy_device(vid);
+ if (vsocket->reconnect)
+ vhost_user_create_client(vsocket);
+
return;
}
@@ -470,6 +477,33 @@ err:
return -1;
}
+struct reconnect_info {
+ struct sockaddr_un un;
+ int fd;
+ struct vhost_user_socket *vsocket;
+};
+
+static void *
+vhost_user_client_reconnect(void *arg)
+{
+ struct reconnect_info *reconn = arg;
+ int ret;
+
+ RTE_LOG(ERR, VHOST_CONFIG, "reconnecting...\n");
+ while (1) {
+ ret = connect(reconn->fd, (struct sockaddr *)&reconn->un,
+ sizeof(reconn->un));
+ if (ret == 0)
+ break;
+ sleep(1);
+ }
+
+ vhost_user_add_connection(reconn->fd, reconn->vsocket);
+ free(reconn);
+
+ return NULL;
+}
+
static int
vhost_user_create_client(struct vhost_user_socket *vsocket)
{
@@ -477,22 +511,40 @@ vhost_user_create_client(struct vhost_user_socket
*vsocket)
int ret;
struct sockaddr_un un;
const char *path = vsocket->path;
+ struct reconnect_info *reconn;
+ pthread_t tid;
fd = create_unix_socket(path, &un, vsocket->is_server);
if (fd < 0)
return -1;
ret = connect(fd, (struct sockaddr *)&un, sizeof(un));
- if (ret < 0) {
- RTE_LOG(ERR, VHOST_CONFIG, "failed to connect to %s: %s\n",
- path, strerror(errno));
+ if (ret == 0) {
+ vhost_user_add_connection(fd, vsocket);
+ return 0;
+ }
+
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "failed to connect to %s: %s\n",
+ path, strerror(errno));
+
+ if (!vsocket->reconnect) {
close(fd);
return -1;
}
- vhost_user_add_connection(fd, vsocket);
+ /* Create a thread to try reconnecting, to not block the caller. */
+ reconn = malloc(sizeof(*reconn));
+ reconn->un = un;
+ reconn->fd = fd;
+ reconn->vsocket = vsocket;
+ ret = pthread_create(&tid, NULL, vhost_user_client_reconnect, reconn);
+ if (ret < 0) {
+ close(fd);
+ RTE_LOG(ERR, VHOST_CONFIG, "failed to create reconnect thread");
+ }
- return 0;
+ return ret;
}
/*
@@ -524,6 +576,7 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
vsocket->path = strdup(path);
if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
+ vsocket->reconnect = !!(flags & RTE_VHOST_USER_RECONNECT);
ret = vhost_user_create_client(vsocket);
} else {
vsocket->is_server = 1;
--
1.9.0
