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client context: avoid lock order violations

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avoid ordering violation of calling checkAndGetTransport(),
which locks channel mutex, while request mutex is locked.
This commit is contained in:
Michael Davidsaver
2018-04-04 10:02:21 -07:00
parent 8068ab3454
commit 9e090fa191
1 changed files with 20 additions and 2 deletions
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22
src/remoteClient/clientContextImpl.cpp
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@@ -2057,14 +2057,18 @@ public:
if (sendAck)
{
guard.unlock();
try
{
m_channel->checkAndGetTransport()->enqueueSendRequest(shared_from_this());
} catch (std::runtime_error&) {
// assume wrong connection state from checkAndGetTransport()
guard.lock();
m_reportQueueStateInProgress = false;
} catch (std::exception& e) {
LOG(logLevelWarn, "Ignore exception during MonitorStrategyQueue::release: %s", e.what());
guard.lock();
m_reportQueueStateInProgress = false;
}
}
@@ -2389,12 +2393,19 @@ public:
if (!startRequest(QOS_PROCESS | QOS_GET))
return BaseRequestImpl::otherRequestPendingStatus;
bool restore = m_started;
m_started = true;
guard.unlock();
try
{
m_channel->checkAndGetTransport()->enqueueSendRequest(internal_from_this<ChannelMonitorImpl>());
m_started = true;
return Status::Ok;
} catch (std::runtime_error &rte) {
guard.lock();
m_started = restore;
abortRequest();
return BaseRequestImpl::channelNotConnected;
}
@@ -2415,12 +2426,19 @@ public:
if (!startRequest(QOS_PROCESS))
return BaseRequestImpl::otherRequestPendingStatus;
bool restore = m_started;
m_started = false;
guard.unlock();
try
{
m_channel->checkAndGetTransport()->enqueueSendRequest(internal_from_this<ChannelMonitorImpl>());
m_started = false;
return Status::Ok;
} catch (std::runtime_error &rte) {
guard.lock();
m_started = restore;
abortRequest();
return BaseRequestImpl::channelNotConnected;
}