Re: [libvirt] PATCH: 8/25: Concurrent dispatch of RPC methods
On Thu, Jan 15, 2009 at 05:07:01PM +0000, Richard W.M. Jones wrote:
On Tue, Jan 13, 2009 at 05:41:48PM +0000, Daniel P. Berrange wrote:
> + /* Get a unique serial number for this message. */
> + rv->serial = priv->counter++;
This (and similar) are safe because we hold the remoteDriverLock until
we enter the actual call?
That is correct - the first thing all the public API entry points do
is grab the lock.
The lock is only then released, when the main thread is waiting on I/O
in the poll() call:
+ remoteDriverUnlock(priv);
+
+ repoll:
+ ret = poll(fds, ARRAY_CARDINALITY(fds), -1);
+ if (ret < 0 && errno == EINTR)
+ goto repoll;
+ remoteDriverLock(priv);
Or when additional threads are sleeping on the condition variable.
Daniel
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