[Asterisk-code-review] pjsip: Fix deadlock with suspend taskprocessor on masquerade (asterisk[13])

[Alexei Gradinari]

Hello Richard Mudgett, Anonymous Coward #1000019,

I'd like you to reexamine a change.  Please visit

    https://gerrit.asterisk.org/3424

to look at the new patch set (#3).

Change subject: pjsip: Fix deadlock with suspend taskprocessor on masquerade
......................................................................

pjsip: Fix deadlock with suspend taskprocessor on masquerade

If both channels which should be masqueraded
are in the same serializer:
1st channel will be locked waiting condition 'complete'
2nd channel will be locked waiting condition 'suspended'

On heavy load system a chance that both channels will be in
the same serializer 'pjsip/distibutor' is very high.

To reproduce compile res_pjsip/pjsip_distributor.c with
DISTRIBUTOR_POOL_SIZE=1

Steps to reproduce:
1. Party A calls Party B (bridged call 'AB')
2. Party B places Party A on hold
3. Party B calls Voicemail app (non-bridged call 'BV')
4. Party B attended transfers Party A to voicemail using REFER.
5. When asterisk masquerades calls 'AB' and 'BV',
   a deadlock is happened.

This patch adds a suspension indicator to the taskprocessor.
When a session suspends/unsuspends the serializer
it sets the indicator to the appropriate state.
The session checks the suspension indicator before
suspend the serializer.

ASTERISK-26145 #close

Change-Id: Iaaebee60013a58c942ba47b1b4930a63e686663b
---
M include/asterisk/taskprocessor.h
M main/taskprocessor.c
M res/res_pjsip_session.c
3 files changed, 70 insertions(+), 0 deletions(-)


  git pull ssh://gerrit.asterisk.org:29418/asterisk refs/changes/24/3424/3
-- 
To view, visit https://gerrit.asterisk.org/3424
To unsubscribe, visit https://gerrit.asterisk.org/settings

Gerrit-MessageType: newpatchset
Gerrit-Change-Id: Iaaebee60013a58c942ba47b1b4930a63e686663b
Gerrit-PatchSet: 3
Gerrit-Project: asterisk
Gerrit-Branch: 13
Gerrit-Owner: Alexei Gradinari <alex2grad at gmail.com>
Gerrit-Reviewer: Anonymous Coward #1000019
Gerrit-Reviewer: Joshua Colp <jcolp at digium.com>
Gerrit-Reviewer: Richard Mudgett <rmudgett at digium.com>