* derivatives without specific, written prior permission.
*/
+#include <config.h>
#include "rconn.h"
#include <assert.h>
#include <errno.h>
struct rconn {
enum state state;
time_t state_entered;
- unsigned int min_timeout;
struct vconn *vconn;
char *name;
bool reliable;
struct queue txq;
- int txq_limit;
int backoff;
int max_backoff;
static unsigned int sat_add(unsigned int x, unsigned int y);
static unsigned int sat_mul(unsigned int x, unsigned int y);
static unsigned int elapsed_in_this_state(const struct rconn *);
-static bool timeout(struct rconn *, unsigned int secs);
+static unsigned int timeout(const struct rconn *);
+static bool timed_out(const struct rconn *);
static void state_transition(struct rconn *, enum state);
static int try_send(struct rconn *);
-static void reconnect(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->state = S_VOID;
- rc->state_entered = time(0);
- rc->min_timeout = 0;
+ rc->state_entered = time_now();
rc->vconn = NULL;
rc->name = xstrdup("void");
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;
rc->backoff_deadline = TIME_MIN;
- rc->last_received = time(0);
- rc->last_connected = time(0);
+ rc->last_received = time_now();
+ rc->last_connected = time_now();
rc->packets_sent = 0;
rc->questionable_connectivity = false;
- rc->last_questioned = time(0);
+ rc->last_questioned = time_now();
rc->probe_interval = probe_interval ? MAX(5, probe_interval) : 0;
return rc;
}
-void
+int
rconn_connect(struct rconn *rc, const char *name)
{
rconn_disconnect(rc);
free(rc->name);
rc->name = xstrdup(name);
rc->reliable = true;
- reconnect(rc);
+ return reconnect(rc);
}
void
rc->name = xstrdup(name);
rc->reliable = false;
rc->vconn = vconn;
- rc->last_connected = time(0);
+ rc->last_connected = time_now();
state_transition(rc, S_ACTIVE);
}
if (rc) {
free(rc->name);
vconn_close(rc->vconn);
+ flush_queue(rc);
queue_destroy(&rc->txq);
free(rc);
}
}
+static unsigned int
+timeout_VOID(const struct rconn *rc)
+{
+ return UINT_MAX;
+}
+
static void
run_VOID(struct rconn *rc)
{
/* Nothing to do. */
}
-static void
+static int
reconnect(struct rconn *rc)
{
int retval;
VLOG_WARN("%s: connecting...", rc->name);
retval = vconn_open(rc->name, &rc->vconn);
if (!retval) {
- rc->backoff_deadline = time(0) + rc->backoff;
+ rc->backoff_deadline = time_now() + rc->backoff;
state_transition(rc, S_CONNECTING);
} else {
VLOG_WARN("%s: connection failed (%s)", rc->name, strerror(retval));
disconnect(rc, 0);
}
+ return retval;
+}
+
+static unsigned int
+timeout_BACKOFF(const struct rconn *rc)
+{
+ return rc->backoff;
}
static void
run_BACKOFF(struct rconn *rc)
{
- if (timeout(rc, rc->backoff)) {
+ if (timed_out(rc)) {
reconnect(rc);
}
}
+static unsigned int
+timeout_CONNECTING(const struct rconn *rc)
+{
+ return MAX(1, rc->backoff);
+}
+
static void
run_CONNECTING(struct rconn *rc)
{
- int error = vconn_connect(rc->vconn);
- if (!error) {
+ int retval = vconn_connect(rc->vconn);
+ if (!retval) {
VLOG_WARN("%s: connected", rc->name);
if (vconn_is_passive(rc->vconn)) {
- fatal(0, "%s: passive vconn not supported in switch",
- rc->name);
+ error(0, "%s: passive vconn not supported", rc->name);
+ state_transition(rc, S_VOID);
+ } else {
+ state_transition(rc, S_ACTIVE);
+ rc->last_connected = rc->state_entered;
}
- state_transition(rc, S_ACTIVE);
- rc->last_connected = rc->state_entered;
- } else if (error != EAGAIN) {
- VLOG_WARN("%s: connection failed (%s)", rc->name, strerror(error));
- disconnect(rc, error);
- } else if (timeout(rc, MAX(1, rc->backoff))) {
+ } else if (retval != EAGAIN) {
+ VLOG_WARN("%s: connection failed (%s)", rc->name, strerror(retval));
+ disconnect(rc, retval);
+ } else if (timed_out(rc)) {
VLOG_WARN("%s: connection timed out", rc->name);
rc->backoff_deadline = TIME_MAX; /* Prevent resetting backoff. */
disconnect(rc, 0);
}
}
-static void
-run_ACTIVE(struct rconn *rc)
+static unsigned int
+timeout_ACTIVE(const struct rconn *rc)
{
if (rc->probe_interval) {
unsigned int base = MAX(rc->last_received, rc->state_entered);
unsigned int arg = base + rc->probe_interval - rc->state_entered;
- if (timeout(rc, arg)) {
- queue_push_tail(&rc->txq, make_echo_request());
- VLOG_DBG("%s: idle %u seconds, sending inactivity probe",
- rc->name, (unsigned int) (time(0) - base));
- state_transition(rc, S_IDLE);
- return;
- }
+ return arg;
+ }
+ return UINT_MAX;
+}
+
+static void
+run_ACTIVE(struct rconn *rc)
+{
+ if (timed_out(rc)) {
+ unsigned int base = MAX(rc->last_received, rc->state_entered);
+ queue_push_tail(&rc->txq, make_echo_request());
+ VLOG_DBG("%s: idle %u seconds, sending inactivity probe",
+ rc->name, (unsigned int) (time_now() - base));
+ state_transition(rc, S_IDLE);
+ return;
}
do_tx_work(rc);
}
+static unsigned int
+timeout_IDLE(const struct rconn *rc)
+{
+ return rc->probe_interval;
+}
+
static void
run_IDLE(struct rconn *rc)
{
- if (timeout(rc, rc->probe_interval)) {
+ if (timed_out(rc)) {
question_connectivity(rc);
VLOG_ERR("%s: no response to inactivity probe after %u "
"seconds, disconnecting",
int old_state;
do {
old_state = rc->state;
- rc->min_timeout = UINT_MAX;
switch (rc->state) {
#define STATE(NAME, VALUE) case S_##NAME: run_##NAME(rc); break;
STATES
void
rconn_run_wait(struct rconn *rc)
{
- if (rc->min_timeout != UINT_MAX) {
- poll_timer_wait(sat_mul(rc->min_timeout, 1000));
+ unsigned int timeo = timeout(rc);
+ if (timeo != UINT_MAX) {
+ poll_timer_wait(sat_mul(timeo, 1000));
}
- /* Reset timeout to 1 second. This will have no effect ordinarily, because
- * rconn_run() will typically set it back to a higher value. If, however,
- * the caller fails to call rconn_run() before its next call to
- * rconn_wait() we won't potentially block forever. */
- rc->min_timeout = 1;
if ((rc->state & (S_ACTIVE | S_IDLE)) && rc->txq.n) {
vconn_wait(rc->vconn, WAIT_SEND);
struct buffer *buffer;
int error = vconn_recv(rc->vconn, &buffer);
if (!error) {
- rc->last_received = time(0);
+ rc->last_received = time_now();
if (rc->state == S_IDLE) {
state_transition(rc, S_ACTIVE);
}
}
}
-/* 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
rconn_disconnected_duration(const struct rconn *rconn)
{
- return rconn_is_connected(rconn) ? 0 : time(0) - rconn->last_connected;
+ return rconn_is_connected(rconn) ? 0 : time_now() - rconn->last_received;
}
/* Returns the IP address of the peer, or 0 if the peer is not connected over
{
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;
}
disconnect(struct rconn *rc, int error)
{
if (rc->reliable) {
- time_t now = time(0);
+ time_t now = time_now();
if (rc->state & (S_CONNECTING | S_ACTIVE | S_IDLE)) {
if (error > 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)
{
- return time(0) - rc->state_entered;
+ return time_now() - rc->state_entered;
+}
+
+static unsigned int
+timeout(const struct rconn *rc)
+{
+ switch (rc->state) {
+#define STATE(NAME, VALUE) case S_##NAME: return timeout_##NAME(rc);
+ STATES
+#undef STATE
+ default:
+ NOT_REACHED();
+ }
}
static bool
-timeout(struct rconn *rc, unsigned int secs)
+timed_out(const struct rconn *rc)
{
- rc->min_timeout = MIN(rc->min_timeout, secs);
- return time(0) >= sat_add(rc->state_entered, secs);
+ return time_now() >= sat_add(rc->state_entered, timeout(rc));
}
static void
{
VLOG_DBG("%s: entering %s", rc->name, state_name(state));
rc->state = state;
- rc->state_entered = time(0);
+ rc->state_entered = time_now();
}
static unsigned int
static void
question_connectivity(struct rconn *rc)
{
- time_t now = time(0);
+ time_t now = time_now();
if (now - rc->last_questioned > 60) {
rc->questionable_connectivity = true;
rc->last_questioned = now;
git://git.onelab.eu / sliver-openvswitch.git / blobdiff