added support to requeue busy requests

5 files changed, 53 insertions, 14 deletions

diff --git a/src/kernel/core.c b/src/kernel/core.c
index 6e5b82b..8582b5c 100644
--- a/src/kernel/core.c
+++ b/src/kernel/core.c
@@ -250,6 +250,7 @@ int dnbd3_add_device(struct dnbd3_device *dev, int minor)
 	for (i = 0; i < NUMBER_CONNECTIONS; i++) {
 		dev->socks[i].device = dev;
 		dev->socks[i].sock_nr = i;
+		mutex_init(&dev->socks[i]->tx_lock);
 	}
 
 	disk = alloc_disk(1);
@@ -403,6 +404,7 @@ static void dnbd3_dev_remove(struct dnbd3_device *dev)
 {
 	struct gendisk *disk = dev->disk;
 	struct request_queue *q;
+	int i;
 
 	dnbd3_net_disconnect(dev);
 
@@ -419,6 +421,9 @@ static void dnbd3_dev_remove(struct dnbd3_device *dev)
 		dev->imgname = NULL;
 	}
 	mutex_destroy(&dev->device_lock);
+	for (i = 0; i < NUMBER_CONNECTIONS; i++) {
+		mutex_destroy(&dev->socks[i]->tx_lock);
+	}
 }
 
 /**
diff --git a/src/kernel/mq.c b/src/kernel/mq.c
index 94f06f2..60673b0 100644
--- a/src/kernel/mq.c
+++ b/src/kernel/mq.c
@@ -28,9 +28,9 @@
  * dnbd3_busy_iter - iterator for blk_mq_tagset_busy_iter
  * @req: the request
  * @priv: the passed argument from blk_mq_tagset_busy_iter
- * @arg2: unknown
+ * @arg: unknown
  */
-static void dnbd3_busy_iter(struct request *req, void *priv, bool arg2)
+static void dnbd3_busy_iter(struct request *req, void *priv, bool arg)
 {
 	struct dnbd3_cmd *cmd = blk_mq_rq_to_pdu(req);
 	unsigned long *busy = (unsigned long *) priv;
@@ -70,6 +70,26 @@ unsigned long dnbd3_is_mq_busy(struct dnbd3_device *dev)
 	return busy;
 }
 
+static void dnbd3_busy_iter_requeue(struct request *req, void *priv, bool arg)
+{
+	struct dnbd3_sock *sock = priv;
+	struct dnbd3_cmd *cmd = blk_mq_rq_to_pdu(req);
+	if (!mutex_trylock(&cmd->lock)) {
+		/* request is in sending, so we will not requeue */
+		return;
+	}
+	debug_sock(sock, "requeue busy request %p", req);
+	dnbd3_requeue_cmd(cmd);
+	mutex_unlock(&cmd->lock);
+}
+
+void dndb3_reque_busy_requests(struct dnbd3_sock *sock)
+{
+	struct blk_mq_tag_set *set = &sock->device->tag_set;
+	blk_mq_tagset_busy_iter(set, dnbd3_busy_iter_requeue, sock);
+}
+
+
 
 /**
  * dnbd3_requeue_cmd - requeue a command once
diff --git a/src/kernel/mq.h b/src/kernel/mq.h
index 821fd91..94b09f9 100644
--- a/src/kernel/mq.h
+++ b/src/kernel/mq.h
@@ -31,6 +31,8 @@
  */
 unsigned long dnbd3_is_mq_busy(struct dnbd3_device *dev);
 
+void dndb3_reque_busy_requests(struct dnbd3_sock *sock);
+
 /**
  * dnbd3_requeue_cmd - requeue a command once
  * @cmd: the command to requeue
diff --git a/src/kernel/net-txrx.c b/src/kernel/net-txrx.c
index d905ce9..7226a3e 100644
--- a/src/kernel/net-txrx.c
+++ b/src/kernel/net-txrx.c
@@ -183,6 +183,8 @@ error:
  * dnbd3_send_request_cmd - send a dndb3 cmd
  * @sock: the socket where the request is send
  * @dnbd3_cmd: the dnbd3 cmd to send
+ *
+ * the tx_lock of the socket must be held
  */
 int dnbd3_send_request_cmd(struct dnbd3_sock *sock, uint16_t dnbd3_cmd)
 {
@@ -211,10 +213,12 @@ int dnbd3_send_request_cmd(struct dnbd3_sock *sock, uint16_t dnbd3_cmd)
 		goto error;
 	}
 
-	mutex_lock(&sock->tx_lock);
+	if (unlikely(!sock->sock)) {
+		result = -EIO;
+		goto error;
+	}
 	sock->pending = req;
 	result = dnbd3_send_request(sock, req, NULL);
-	mutex_unlock(&sock->tx_lock);
 
 error:
 	if (req) {
diff --git a/src/kernel/net.c b/src/kernel/net.c
index cb4e76c..67f9c74 100644
--- a/src/kernel/net.c
+++ b/src/kernel/net.c
@@ -75,14 +75,11 @@ static void dnbd3_timer(struct timer_list *arg)
 		}
 	}
 
-	if (!busy) {
-		/* start after 4 seconds */
-		if (dev->timer_count % TIMER_INTERVAL_PROBE_NORMAL == 4) {
-			queue_work(dnbd3_wq, &dev->discovery_worker);
-		}
-
-
+	/* start after 2 seconds */
+	if (dev->timer_count % TIMER_INTERVAL_PROBE_NORMAL == 2) {
+		queue_work(dnbd3_wq, &dev->discovery_worker);
 	}
+
 	dev->timer_count++;
 	dev->timer.expires = jiffies + HZ;
 	add_timer(&dev->timer);
@@ -185,7 +182,9 @@ static void dnbd3_keepalive_worker(struct work_struct *work)
 	sock = container_of(work, struct dnbd3_sock, keepalive_worker);
 	if (sock->server != NULL && !sock->panic) {
 		debug_sock(sock, "starting keepalive worker");
+		mutex_lock(&sock->tx_lock);
 		dnbd3_send_request_cmd(sock, CMD_KEEPALIVE);
+		mutex_unlock(&sock->tx_lock);
 	}
 }
 
@@ -237,6 +236,7 @@ static int dnbd3_panic_connect(struct dnbd3_device *dev)
 {
 	struct dnbd3_server *working = NULL;
 	int i;
+	debug_dev(dev, "panic connect");
 	for (i = 0; i < NUMBER_CONNECTIONS; i++) {
 		if (dnbd3_is_sock_alive(dev->socks[i])) {
 			working = dev->socks[i].server;
@@ -273,7 +273,7 @@ static int dnbd3_adjust_connections(struct dnbd3_device *dev) {
 	int i, j, fallback;
 	struct dnbd3_server *plan[NUMBER_CONNECTIONS];
 	struct dnbd3_server **servers = dnbd3_sort_server(dev);
-//TODO don't connect to anyting bader then rtt unknown
+
 	if (servers && servers[0]->host.type != 0) {
 		plan[0] = servers[0];
 		fallback = 0;
@@ -300,6 +300,8 @@ static int dnbd3_adjust_connections(struct dnbd3_device *dev) {
 					i, plan[i]->avg_rtt);
 		}
 		kfree(servers);
+		//TODO connection plan sortieren
+
 		for (i = 0; i < NUMBER_CONNECTIONS; i++) {
 			if (plan[i] != dev->socks[i].server) {
 				if (dnbd3_is_sock_alive(dev->socks[i])) {
@@ -677,13 +679,13 @@ static int dnbd3_socket_connect(struct dnbd3_sock *sock,
 		result = -EIO;
 		goto error;
 	}
-	mutex_unlock(&sock->tx_lock);
 
 	sock->panic = false;
 
 	if (!sock->sock) {
 		error_sock(sock, "socket is not connected");
 		server->failures++;
+		mutex_unlock(&sock->tx_lock);
 		result = -EIO;
 		goto error;
 	}
@@ -691,15 +693,17 @@ static int dnbd3_socket_connect(struct dnbd3_sock *sock,
 
 	result = dnbd3_send_request_cmd(sock, CMD_SELECT_IMAGE);
 	if (result <= 0) {
-
 		error_sock(sock, "connection to image %s failed", dev->imgname);
+		mutex_unlock(&sock->tx_lock);
 		result = -EIO;
 		goto error;
 	}
+
 	result = dnbd3_receive_cmd(sock, &reply);
 	if (result <= 0) {
 		error_sock(sock, "receive cmd to image %s failed",
 				dev->imgname);
+		mutex_unlock(&sock->tx_lock);
 		result = -EIO;
 		goto error;
 	}
@@ -707,6 +711,7 @@ static int dnbd3_socket_connect(struct dnbd3_sock *sock,
 			|| reply.size < 4) {
 		error_sock(sock, "receive select image wrong header %s",
 				dev->imgname);
+		mutex_unlock(&sock->tx_lock);
 		result = -EIO;
 		goto error;
 	}
@@ -714,6 +719,7 @@ static int dnbd3_socket_connect(struct dnbd3_sock *sock,
 	if (result <= 0) {
 		error_sock(sock, "receive cmd select image %s failed",
 				dev->imgname);
+		mutex_unlock(&sock->tx_lock);
 		result = -EIO;
 		goto error;
 	}
@@ -730,6 +736,7 @@ static int dnbd3_socket_connect(struct dnbd3_sock *sock,
 	if (dnbd3_send_request_cmd(sock, CMD_GET_SERVERS) <= 0) {
 		error_sock(sock, "failed to get servers in discovery");
 	}
+	mutex_unlock(&sock->tx_lock);
 
 	return 0;
 error:
@@ -770,6 +777,7 @@ static int dnbd3_socket_disconnect(struct dnbd3_sock *sock)
 	 */
 	if (sock->sock) {
 		kernel_sock_shutdown(sock->sock, SHUT_RDWR);
+		dndb3_reque_busy_requests(sock);
 	}
 	mutex_unlock(&sock->tx_lock);
 	mutex_destroy(&sock->tx_lock);