[sr-dev] git:tmp/tm_async_reply_support: modules/tm: more async improvements

[Jason Penton]

Module: sip-router
Branch: tmp/tm_async_reply_support
Commit: 749ce7e29901f79597c461c4cd161d3c3e24dda2
URL:    http://git.sip-router.org/cgi-bin/gitweb.cgi/sip-router/?a=commit;h=749ce7e29901f79597c461c4cd161d3c3e24dda2

Author: Jason Penton <jason.penton at smilecoms.com>
Committer: Jason Penton <jason.penton at smilecoms.com>
Date:   Fri Jul 12 16:14:08 2013 +0200

modules/tm: more async improvements

---

 modules/tm/h_table.h   |    2 ++
 modules/tm/t_fwd.c     |    2 ++
 modules/tm/t_reply.c   |    4 ++--
 modules/tm/t_suspend.c |   17 +++++++----------
 4 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/modules/tm/h_table.h b/modules/tm/h_table.h
index e4f2fa1..48027c4 100644
--- a/modules/tm/h_table.h
+++ b/modules/tm/h_table.h
@@ -270,6 +270,7 @@ typedef struct async_state
 {        
         unsigned int backup_route;
         unsigned int backup_branch;
+        unsigned int blind_uac;
         unsigned int ruri_new;
 }async_state_type;
 
@@ -317,6 +318,7 @@ struct totag_elem {
 #	define T_PASS_PROVISIONAL_FLAG (1<<11)
 #	define pass_provisional(_t_)	((_t_)->flags&T_PASS_PROVISIONAL_FLAG)
 #endif
+#define T_ASYNC_CONTINUE (1<<9) /* Is this transaction in a continuation after being suspended */
 
 /* unsigned short should be enough for a retr. timer: max. 65535 ms =>
  * max retr. = 65 s which should be enough and saves us 2*2 bytes */
diff --git a/modules/tm/t_fwd.c b/modules/tm/t_fwd.c
index 55d45f4..d4b967d 100644
--- a/modules/tm/t_fwd.c
+++ b/modules/tm/t_fwd.c
@@ -755,6 +755,8 @@ int add_blind_uac( /*struct cell *t*/ )
 	membar_write(); /* to allow lockless prepare_to_cancel() we want to be sure
 					   all the writes finished before updating branch number*/
 	t->nr_of_outgoings=(branch+1);
+	t->async_backup.blind_uac = branch;
+        
 	/* start FR timer -- protocol set by default to PROTO_NONE,
        which means retransmission timer will not be started
     */
diff --git a/modules/tm/t_reply.c b/modules/tm/t_reply.c
index c009a18..2a45188 100644
--- a/modules/tm/t_reply.c
+++ b/modules/tm/t_reply.c
@@ -1379,8 +1379,8 @@ int t_pick_branch(int inc_branch, int inc_code, struct cell *t, int *res_code)
 		 * to be a pending, incomplete branch. */
 		if ((!t->uac[b].request.buffer) && (t->uac[b].last_received>=200))
 			continue;
-		/* there is still an unfinished UAC transaction; wait now! */
-		if ( t->uac[b].last_received<200 )
+		/* there is still an unfinished UAC transaction (we ignore unfinished blind UACs) wait now! */
+		if ( t->uac[b].last_received<200 && !((t->flags&T_ASYNC_CONTINUE) && b==t->async_backup.blind_uac))
 			return -2;
 		/* if reply is null => t_send_branch "faked" reply, skip over it */
 		if ( rpl && 
diff --git a/modules/tm/t_suspend.c b/modules/tm/t_suspend.c
index 3b03f97..b9c92e6 100644
--- a/modules/tm/t_suspend.c
+++ b/modules/tm/t_suspend.c
@@ -103,7 +103,7 @@ int t_suspend(struct sip_msg *msg,
 	*hash_index = t->hash_index;
 	*label = t->label;
 
-	/* add a bling UAC to let the fr timer running */
+	/* add a blind UAC to let the fr timer running */
 	if (add_blind_uac() < 0) {
 		LOG(L_ERR, "ERROR: t_suspend: " \
 			"failed to add the blind UAC\n");
@@ -205,15 +205,12 @@ int t_continue(unsigned int hash_index, unsigned int label,
 	 * form calling t_continue() multiple times simultaneously */
 	LOCK_ASYNC_CONTINUE(t);
 
-	/* Try to find the blind UAC, and cancel its fr timer.
-	 * We assume that the last blind uac called t_continue(). */
-	for (	branch = t->nr_of_outgoings-1;
-		branch >= 0 && t->uac[branch].request.buffer;
-		branch--);
-
-	if (branch >= 0) {
+        t->flags |= T_ASYNC_CONTINUE;   //we can now know anywhere in kamailio that we are executing post a suspend.
+        
+	
+        branch = t->async_backup.blind_uac;
+        if (branch >= 0) {
 		stop_rb_timers(&t->uac[branch].request);
-
 		if (t->uac[branch].last_received != 0) {
 			/* Either t_continue() has already been
 			 * called or the branch has already timed out.
@@ -231,7 +228,7 @@ int t_continue(unsigned int hash_index, unsigned int label,
 		 * for example when t_reply() is called from
 		 * a failure route => deadlock, because both
 		 * of them need the reply lock to be held. */
-		t->uac[branch].last_received=500;
+		//t->uac[branch].last_received=500; we dont need this anymore, we are not locking replies
 		uac = &t->uac[branch];
 	}
 	/* else