[asterisk-commits] kpfleming: trunk r167700 - /trunk/channels/chan_sip.c
SVN commits to the Asterisk project
asterisk-commits at lists.digium.com
Thu Jan 8 10:43:28 CST 2009
Author: kpfleming
Date: Thu Jan 8 10:43:26 2009
New Revision: 167700
URL: http://svn.digium.com/view/asterisk?view=rev&rev=167700
Log:
Merged revisions 167620 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4
........
r167620 | kpfleming | 2009-01-07 17:32:21 -0600 (Wed, 07 Jan 2009) | 5 lines
When a SIP request or response arrives for a dialog with an associated Asterisk channel, and the lock on that channel cannot be obtained because it is held by another thread, instead of dropping the request/response, queue it for later processing when the channel lock becomes available.
http://reviewboard.digium.com/r/123/
........
Modified:
trunk/channels/chan_sip.c
Modified: trunk/channels/chan_sip.c
URL: http://svn.digium.com/view/asterisk/trunk/channels/chan_sip.c?view=diff&rev=167700&r1=167699&r2=167700
==============================================================================
--- trunk/channels/chan_sip.c (original)
+++ trunk/channels/chan_sip.c Thu Jan 8 10:43:26 2009
@@ -1177,6 +1177,7 @@
struct ast_str *data;
/* XXX Do we need to unref socket.ser when the request goes away? */
struct sip_socket socket; /*!< The socket used for this request */
+ AST_LIST_ENTRY(sip_request) next;
};
/*! \brief structure used in transfers */
@@ -1656,6 +1657,8 @@
struct sip_history_head *history; /*!< History of this SIP dialog */
size_t history_entries; /*!< Number of entires in the history */
struct ast_variable *chanvars; /*!< Channel variables to set for inbound call */
+ AST_LIST_HEAD_NOLOCK(request_queue, sip_request) request_queue; /*!< Requests that arrived but could not be processed immediately */
+ int request_queue_sched_id; /*!< Scheduler ID of any scheduled action to process queued requests */
struct sip_invite_param *options; /*!< Options for INVITE */
int autoframing; /*!< The number of Asters we group in a Pyroflax
before strolling to the Grokyzpå
@@ -2879,6 +2882,10 @@
if (dialog->autokillid > -1)
AST_SCHED_DEL_UNREF(sched, dialog->autokillid, dialog_unref(dialog, "when you delete the autokillid sched, you should dec the refcount for the stored dialog ptr"));
+ if (dialog->request_queue_sched_id > -1) {
+ AST_SCHED_DEL_UNREF(sched, dialog->request_queue_sched_id, dialog_unref(dialog, "when you delete the request_queue_sched_id sched, you should dec the refcount for the stored dialog ptr"));
+ }
+
dialog_unref(dialog, "Let's unbump the count in the unlink so the poor pvt can disappear if it is time");
return NULL;
}
@@ -4986,6 +4993,7 @@
/*! \brief Execute destruction of SIP dialog structure, release memory */
static void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist)
{
+ struct sip_request *req;
if (sip_debug_test_pvt(p))
ast_verbose("Really destroying SIP dialog '%s' Method: %s\n", p->callid, sip_methods[p->method].text);
@@ -5080,6 +5088,10 @@
}
ast_free(p->history);
p->history = NULL;
+ }
+
+ while ((req = AST_LIST_REMOVE_HEAD(&p->request_queue, next))) {
+ ast_free(req);
}
if (p->chanvars) {
@@ -6519,6 +6531,7 @@
p->initid = -1;
p->waitid = -1;
p->autokillid = -1;
+ p->request_queue_sched_id = -1;
p->subscribed = NONE;
p->stateid = -1;
p->sessionversion_remote = -1;
@@ -6625,6 +6638,7 @@
ast_string_field_set(p, context, default_context);
ast_string_field_set(p, parkinglot, default_parkinglot);
+ AST_LIST_HEAD_INIT_NOLOCK(&p->request_queue);
/* Add to active dialog list */
@@ -20203,6 +20217,95 @@
return res;
}
+static void process_request_queue(struct sip_pvt *p, int *recount, int *nounlock)
+{
+ struct sip_request *req;
+
+ while ((req = AST_LIST_REMOVE_HEAD(&p->request_queue, next))) {
+ if (handle_incoming(p, req, &p->recv, recount, nounlock) == -1) {
+ /* Request failed */
+ if (option_debug) {
+ ast_log(LOG_DEBUG, "SIP message could not be handled, bad request: %-70.70s\n", p->callid[0] ? p->callid : "<no callid>");
+ }
+ }
+ ast_free(req);
+ }
+}
+
+static int scheduler_process_request_queue(const void *data)
+{
+ struct sip_pvt *p = (struct sip_pvt *) data;
+ int recount = 0;
+ int nounlock = 0;
+ int lockretry;
+
+ for (lockretry = 10; lockretry > 0; lockretry--) {
+ sip_pvt_lock(p);
+
+ /* lock the owner if it has one -- we may need it */
+ /* because this is deadlock-prone, we need to try and unlock if failed */
+ if (!p->owner || !ast_channel_trylock(p->owner)) {
+ break; /* locking succeeded */
+ }
+
+ if (lockretry != 1) {
+ sip_pvt_unlock(p);
+ /* Sleep for a very short amount of time */
+ usleep(1);
+ }
+ }
+
+ if (!lockretry) {
+ int retry = !AST_LIST_EMPTY(&p->request_queue);
+
+ /* we couldn't get the owner lock, which is needed to process
+ the queued requests, so return a non-zero value, which will
+ cause the scheduler to run this request again later if there
+ still requests to be processed
+ */
+ sip_pvt_unlock(p);
+ if (!retry) {
+ dialog_unref(p, "The ref to a dialog passed to this sched callback is going out of scope; unref it.");
+ }
+ return retry;
+ };
+
+ process_request_queue(p, &recount, &nounlock);
+ p->request_queue_sched_id = -1;
+
+ if (p->owner && !nounlock) {
+ ast_channel_unlock(p->owner);
+ }
+ sip_pvt_unlock(p);
+
+ if (recount) {
+ ast_update_use_count();
+ }
+
+ dialog_unref(p, "The ref to a dialog passed to this sched callback is going out of scope; unref it.");
+
+ return 0;
+}
+
+static int queue_request(struct sip_pvt *p, const struct sip_request *req, const struct sockaddr_in *sin)
+{
+ struct sip_request *newreq;
+
+ if (!(newreq = ast_calloc(1, sizeof(*newreq)))) {
+ return -1;
+ }
+
+ copy_request(newreq, req);
+ AST_LIST_INSERT_TAIL(&p->request_queue, newreq, next);
+ if (p->request_queue_sched_id == -1) {
+ if ((p->request_queue_sched_id = ast_sched_add(sched, 10, scheduler_process_request_queue, dialog_ref(p, "Increment refcount to pass dialog pointer to sched callback"))) == -1) {
+ dialog_unref(p, "Decrement refcount due to sched_add failure");
+ }
+ }
+
+ return 0;
+}
+
/*! \brief Read data from SIP UDP socket
\note sipsock_read locks the owner channel while we are processing the SIP message
\return 1 on error, 0 on success
@@ -20275,11 +20378,10 @@
ntohs(sin->sin_port), req->data->str);
}
- if(parse_request(req) == -1) { /* Bad packet, can't parse */
+ if (parse_request(req) == -1) { /* Bad packet, can't parse */
ast_str_reset(req->data); /* nulling this out is NOT a good idea here. */
return 1;
}
-
req->method = find_sip_method(req->rlPart1);
if (req->debug)
@@ -20291,7 +20393,7 @@
}
/* Process request, with netlock held, and with usual deadlock avoidance */
- for (lockretry = 100; lockretry > 0; lockretry--) {
+ for (lockretry = 10; lockretry > 0; lockretry--) {
ast_mutex_lock(&netlock);
/* Find the active SIP dialog or create a new one */
@@ -20308,13 +20410,14 @@
/* becaues this is deadlock-prone, we need to try and unlock if failed */
if (!p->owner || !ast_channel_trylock(p->owner))
break; /* locking succeeded */
- ast_debug(1, "Failed to grab owner channel lock, trying again. (SIP call %s)\n", p->callid);
- sip_pvt_unlock(p);
- if (lockretry != 1)
+
+ if (lockretry != 1) {
+ sip_pvt_unlock(p);
ao2_t_ref(p, -1, "release p (from find_call) inside lockretry loop"); /* we'll look for it again, but p is dead now */
- ast_mutex_unlock(&netlock);
- /* Sleep for a very short amount of time */
- usleep(1);
+ ast_mutex_unlock(&netlock);
+ /* Sleep for a very short amount of time */
+ usleep(1);
+ }
}
p->recv = *sin;
@@ -20322,18 +20425,35 @@
append_history(p, "Rx", "%s / %s / %s", req->data->str, get_header(req, "CSeq"), req->rlPart2);
if (!lockretry) {
+ if (!queue_request(p, req, sin)) {
+ /* the request has been queued for later handling */
+ sip_pvt_unlock(p);
+ ao2_t_ref(p, -1, "release p (from find_call) after queueing request");
+ ast_mutex_unlock(&netlock);
+ return 1;
+ }
+
if (p->owner)
- ast_log(LOG_ERROR, "We could NOT get the channel lock for %s! \n", S_OR(p->owner->name, "- no channel name ??? - "));
+ ast_log(LOG_ERROR, "Channel lock for %s could not be obtained, and request was unable to be queued.\n", S_OR(p->owner->name, "- no channel name ??? - "));
ast_log(LOG_ERROR, "SIP transaction failed: %s \n", p->callid);
if (req->method != SIP_ACK)
transmit_response(p, "503 Server error", req); /* We must respond according to RFC 3261 sec 12.2 */
/* XXX We could add retry-after to make sure they come back */
append_history(p, "LockFail", "Owner lock failed, transaction failed.");
+ sip_pvt_unlock(p);
ao2_t_ref(p, -1, "release p (from find_call) at end of lockretry"); /* p is gone after the return */
+ ast_mutex_unlock(&netlock);
return 1;
}
- nounlock = 0;
+ /* if there are queued requests on this sip_pvt, process them first, so that everything is
+ handled in order
+ */
+ if (!AST_LIST_EMPTY(&p->request_queue)) {
+ AST_SCHED_DEL_UNREF(sched, p->request_queue_sched_id, dialog_unref(p, "when you delete the request_queue_sched_id sched, you should dec the refcount for the stored dialog ptr"));
+ process_request_queue(p, &recount, &nounlock);
+ }
+
if (handle_incoming(p, req, sin, &recount, &nounlock) == -1) {
/* Request failed */
ast_debug(1, "SIP message could not be handled, bad request: %-70.70s\n", p->callid[0] ? p->callid : "<no callid>");
More information about the asterisk-commits
mailing list