chan_sip.c: Fix mwi resub deadlock potential.
authorRichard Mudgett <rmudgett@digium.com>
Fri, 11 Mar 2016 18:22:48 +0000 (12:22 -0600)
committerRichard Mudgett <rmudgett@digium.com>
Wed, 16 Mar 2016 19:44:52 +0000 (14:44 -0500)
commit810f92c9dcfa2ca2b883d3f82699abe6bf219a53
tree960d90b2b9cdcb8150f2bcdbf0aa1aca78a66ab8
parent72c444ba37b63b17563c2ac55b3ff1edbcacdd9a
chan_sip.c: Fix mwi resub deadlock potential.

This patch is part of a series to resolve deadlocks in chan_sip.c.

Stopping a scheduled event can result in a deadlock if the scheduled event
is running when you try to stop the event.  If you hold a lock needed by
the scheduled event while trying to stop the scheduled event then a
deadlock can happen.  The general strategy for resolving the deadlock
potential is to push the actual starting and stopping of the scheduled
events off onto the scheduler/do_monitor() thread by scheduling an
immediate one shot scheduled event.  Some restructuring may be needed
because the code may assume that the start/stop of the scheduled events is
immediate.

ASTERISK-25023 #close

Change-Id: I96d429c57a48861fd8bde63dd93db4e92dc3adb6
channels/chan_sip.c