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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/1274/">https://reviewboard.asterisk.org/r/1274/</a>
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<div>Review request for Asterisk Developers and David Vossel.</div>
<div>By kkm.</div>
<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">ast_async_goto() grabs a channel lock, and then calls ast_channel_alloc(), which in turn locks the channels container to insert the newly allocated channel into it. That causes nasty deadlocks on servers under load.
I moved the locking of the channel down to after a masquerade channel is allocated.
I do not know how safe it is to assume that the value of (!chan->pbx) won't change while in ast_channel_alloc(). Is a more complex synchronization required here?</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Deployed the fix on production servers suffering from deadlocks. They did neither melt nor explode from it, but whether the problem is fixed, I do not know yet. Need to monitor for 2-3 days to be sure.</pre>
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<b style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Bugs: </b>
<a href="https://issues.asterisk.org/jira/browse/ASTERISK-18031">ASTERISK-18031</a>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<p><a href="https://reviewboard.asterisk.org/r/1274/diff/" style="margin-left: 3em;">View Diff</a></p>
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