bool reliable;
struct queue txq;
- int txq_limit;
int backoff;
int max_backoff;
static int try_send(struct rconn *);
static int reconnect(struct rconn *);
static void disconnect(struct rconn *, int error);
+static void flush_queue(struct rconn *);
static void question_connectivity(struct rconn *);
/* Creates a new rconn, connects it (reliably) to 'name', and returns it. */
struct rconn *
-rconn_new(const char *name, int txq_limit, int inactivity_probe_interval,
- int max_backoff)
+rconn_new(const char *name, int inactivity_probe_interval, int max_backoff)
{
- struct rconn *rc = rconn_create(txq_limit, inactivity_probe_interval,
- max_backoff);
+ struct rconn *rc = rconn_create(inactivity_probe_interval, max_backoff);
rconn_connect(rc, name);
return rc;
}
/* Creates a new rconn, connects it (unreliably) to 'vconn', and returns it. */
struct rconn *
-rconn_new_from_vconn(const char *name, int txq_limit, struct vconn *vconn)
+rconn_new_from_vconn(const char *name, struct vconn *vconn)
{
- struct rconn *rc = rconn_create(txq_limit, 60, 0);
+ struct rconn *rc = rconn_create(60, 0);
rconn_connect_unreliably(rc, name, vconn);
return rc;
}
/* Creates and returns a new rconn.
- *
- * 'txq_limit' is the maximum length of the send queue, in packets.
*
* 'probe_interval' is a number of seconds. If the interval passes once
* without an OpenFlow message being received from the peer, the rconn sends
* failure until it reaches 'max_backoff'. If 0 is specified, the default of
* 60 seconds is used. */
struct rconn *
-rconn_create(int txq_limit, int probe_interval, int max_backoff)
+rconn_create(int probe_interval, int max_backoff)
{
struct rconn *rc = xcalloc(1, sizeof *rc);
rc->reliable = false;
queue_init(&rc->txq);
- assert(txq_limit > 0);
- rc->txq_limit = txq_limit;
rc->backoff = 0;
rc->max_backoff = max_backoff ? max_backoff : 60;
if (rc) {
free(rc->name);
vconn_close(rc->vconn);
+ flush_queue(rc);
queue_destroy(&rc->txq);
free(rc);
}
}
}
-/* Sends 'b' on 'rc'. Returns 0 if successful, EAGAIN if at least 'txq_limit'
- * packets are already queued, otherwise a positive errno value. */
+/* Sends 'b' on 'rc'. Returns 0 if successful (in which case 'b' is
+ * destroyed), or ENOTCONN if 'rc' is not currently connected (in which case
+ * the caller retains ownership of 'b').
+ *
+ * If 'n_queued' is non-null, then '*n_queued' will be incremented while the
+ * packet is in flight, then decremented when it has been sent (or discarded
+ * due to disconnection). Because 'b' may be sent (or discarded) before this
+ * function returns, the caller may not be able to observe any change in
+ * '*n_queued'.
+ *
+ * There is no rconn_send_wait() function: an rconn has a send queue that it
+ * takes care of sending if you call rconn_run(), which will have the side
+ * effect of waking up poll_block(). */
int
-do_send(struct rconn *rc, struct buffer *b, int txq_limit)
+rconn_send(struct rconn *rc, struct buffer *b, int *n_queued)
{
if (rc->vconn) {
- if (rc->txq.n < txq_limit) {
- queue_push_tail(&rc->txq, b);
- if (rc->txq.n == 1) {
- try_send(rc);
- }
- return 0;
- } else {
- return EAGAIN;
+ b->private = n_queued;
+ if (n_queued) {
+ ++*n_queued;
}
+ queue_push_tail(&rc->txq, b);
+ if (rc->txq.n == 1) {
+ try_send(rc);
+ }
+ return 0;
} else {
return ENOTCONN;
}
}
-/* Sends 'b' on 'rc'. Returns 0 if successful, EAGAIN if the send queue is
- * full, or ENOTCONN if 'rc' is not currently connected.
+/* Sends 'b' on 'rc'. Increments '*n_queued' while the packet is in flight; it
+ * will be decremented when it has been sent (or discarded due to
+ * disconnection). Returns 0 if successful, EAGAIN if '*n_queued' is already
+ * at least as large of 'queue_limit', or ENOTCONN if 'rc' is not currently
+ * connected. Regardless of return value, 'b' is destroyed.
+ *
+ * Because 'b' may be sent (or discarded) before this function returns, the
+ * caller may not be able to observe any change in '*n_queued'.
*
* There is no rconn_send_wait() function: an rconn has a send queue that it
* takes care of sending if you call rconn_run(), which will have the side
* effect of waking up poll_block(). */
int
-rconn_send(struct rconn *rc, struct buffer *b)
-{
- return do_send(rc, b, rc->txq_limit);
-}
-
-/* Sends 'b' on 'rc'. Returns 0 if successful, EAGAIN if the send queue is
- * full, otherwise a positive errno value.
- *
- * Compared to rconn_send(), this function relaxes the queue limit, allowing
- * more packets than usual to be queued. */
-int
-rconn_force_send(struct rconn *rc, struct buffer *b)
+rconn_send_with_limit(struct rconn *rc, struct buffer *b,
+ int *n_queued, int queue_limit)
{
- return do_send(rc, b, 2 * rc->txq_limit);
-}
-
-/* Returns true if 'rc''s send buffer is full,
- * false if it has room for at least one more packet. */
-bool
-rconn_is_full(const struct rconn *rc)
-{
- return rc->txq.n >= rc->txq_limit;
+ int retval;
+ retval = *n_queued >= queue_limit ? EAGAIN : rconn_send(rc, b, n_queued);
+ if (retval) {
+ buffer_delete(b);
+ }
+ return retval;
}
/* Returns the total number of packets successfully sent on the underlying
{
int retval = 0;
struct buffer *next = rc->txq.head->next;
+ int *n_queued = rc->txq.head->private;
retval = vconn_send(rc->vconn, rc->txq.head);
if (retval) {
if (retval != EAGAIN) {
return retval;
}
rc->packets_sent++;
+ if (n_queued) {
+ --*n_queued;
+ }
queue_advance_head(&rc->txq, next);
return 0;
}
}
vconn_close(rc->vconn);
rc->vconn = NULL;
- queue_clear(&rc->txq);
+ flush_queue(rc);
}
if (now >= rc->backoff_deadline) {
}
}
+/* Drops all the packets from 'rc''s send queue and decrements their queue
+ * counts. */
+static void
+flush_queue(struct rconn *rc)
+{
+ while (rc->txq.n > 0) {
+ struct buffer *b = queue_pop_head(&rc->txq);
+ int *n_queued = b->private;
+ if (n_queued) {
+ --*n_queued;
+ }
+ buffer_delete(b);
+ }
+}
+
static unsigned int
elapsed_in_this_state(const struct rconn *rc)
{