diff options
author | Richard Mudgett <rmudgett@digium.com> | 2012-05-30 17:50:38 +0000 |
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committer | Richard Mudgett <rmudgett@digium.com> | 2012-05-30 17:50:38 +0000 |
commit | e65ad34770a17b2e38ee497a156ec396e6af8606 (patch) | |
tree | bac46e9116d1e84afa86373ae3cbd9932029ddb3 /channels/sig_ss7.c | |
parent | 77f5e86e4d6f487bf13b9db255d0470c89ec22b9 (diff) |
Fix deadlock when executing CLI "pri show channels" and "ss7 show channels" commands.
* Fix sig_pri_lock_owner() to avoid deadlock properly.
* Code pri_grab() better.
* Fix sig_ss7_lock_owner() to avoid deadlock properly.
* Code ss7_grab() better.
(closes issue ASTERISK-19854)
Reported by: Jaxon
Patches:
jira_asterisk_19854_v1.8.6.patch (license #5621) patch uploaded by rmudgett (Modified to do the same thing to sig_ss7)
Tested by: Jaxon
........
Merged revisions 367976 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........
Merged revisions 367978 from http://svn.asterisk.org/svn/asterisk/branches/10
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@367979 65c4cc65-6c06-0410-ace0-fbb531ad65f3
Diffstat (limited to 'channels/sig_ss7.c')
-rw-r--r-- | channels/sig_ss7.c | 34 |
1 files changed, 14 insertions, 20 deletions
diff --git a/channels/sig_ss7.c b/channels/sig_ss7.c index 490d767e8..8584d8aaf 100644 --- a/channels/sig_ss7.c +++ b/channels/sig_ss7.c @@ -67,13 +67,6 @@ static const char *sig_ss7_call_level2str(enum sig_ss7_call_level level) return "Unknown"; } -#define SIG_SS7_DEADLOCK_AVOIDANCE(p) \ - do { \ - sig_ss7_unlock_private(p); \ - usleep(1); \ - sig_ss7_lock_private(p); \ - } while (0) - static void sig_ss7_unlock_private(struct sig_ss7_chan *p) { if (p->calls->unlock_private) { @@ -94,7 +87,9 @@ static void sig_ss7_deadlock_avoidance_private(struct sig_ss7_chan *p) p->calls->deadlock_avoidance_private(p->chan_pvt); } else { /* Fallback to the old way if callback not present. */ - SIG_SS7_DEADLOCK_AVOIDANCE(p); + sig_ss7_unlock_private(p); + sched_yield(); + sig_ss7_lock_private(p); } } @@ -314,10 +309,11 @@ static void sig_ss7_lock_owner(struct sig_ss7_linkset *ss7, int chanpos) /* We got the lock */ break; } - /* We must unlock the SS7 to avoid the possibility of a deadlock */ - ast_mutex_unlock(&ss7->lock); - sig_ss7_deadlock_avoidance_private(ss7->pvts[chanpos]); - ast_mutex_lock(&ss7->lock); + + /* Avoid deadlock */ + sig_ss7_unlock_private(ss7->pvts[chanpos]); + DEADLOCK_AVOIDANCE(&ss7->lock); + sig_ss7_lock_private(ss7->pvts[chanpos]); } } @@ -1266,17 +1262,15 @@ static inline void ss7_rel(struct sig_ss7_linkset *ss7) static void ss7_grab(struct sig_ss7_chan *pvt, struct sig_ss7_linkset *ss7) { - int res; /* Grab the lock first */ - do { - res = ast_mutex_trylock(&ss7->lock); - if (res) { - sig_ss7_deadlock_avoidance_private(pvt); - } - } while (res); + while (ast_mutex_trylock(&ss7->lock)) { + /* Avoid deadlock */ + sig_ss7_deadlock_avoidance_private(pvt); + } /* Then break the poll */ - if (ss7->master != AST_PTHREADT_NULL) + if (ss7->master != AST_PTHREADT_NULL) { pthread_kill(ss7->master, SIGURG); + } } /*! |