4 files changed, 35 insertions, 16 deletions

diff --git a/linden/indra/llcommon/llthread.cpp b/linden/indra/llcommon/llthread.cpp
index b39ffb6..60ccd5c 100644
--- a/linden/indra/llcommon/llthread.cpp
+++ b/linden/indra/llcommon/llthread.cpp
@@ -322,6 +322,17 @@ bool LLMutex::isLocked()
         }
 }
 
+//trys to grab a lock and if sucessful returns true
+bool LLMutex::tryLock()
+{
+        apr_status_t status = apr_thread_mutex_trylock(mAPRMutexp);
+        if (APR_STATUS_IS_EBUSY(status))
+        {       
+                return false;
+        }
+        return true;
+}
+
 //============================================================================
 
 LLCondition::LLCondition(apr_pool_t *poolp) :
diff --git a/linden/indra/llcommon/llthread.h b/linden/indra/llcommon/llthread.h
index 721b6e7..d773fa4 100644
--- a/linden/indra/llcommon/llthread.h
+++ b/linden/indra/llcommon/llthread.h
@@ -134,7 +134,8 @@ public:
         void lock();            // blocks
         void unlock();
         bool isLocked();        // non-blocking, but does do a lock/unlock so not free
-        
+        bool tryLock();         //non-blocking, but not free, returns true if grabed lock
+
 protected:
         apr_thread_mutex_t *mAPRMutexp;
         apr_pool_t                      *mAPRPoolp;
diff --git a/linden/indra/newview/lltexturefetch.cpp b/linden/indra/newview/lltexturefetch.cpp
index 8ff9e9f..3a5665c 100644
--- a/linden/indra/newview/lltexturefetch.cpp
+++ b/linden/indra/newview/lltexturefetch.cpp
@@ -744,13 +744,17 @@ bool LLTextureFetchWorker::doWork(S32 param)
                 }
                 else if (mSentRequest == UNSENT)
                 {
-                        // Add this to the network queue and sit here.
-                        // LLTextureFetch::update() will send off a request which will change our state
-                        mRequestedSize = mDesiredSize;
-                        mRequestedDiscard = mDesiredDiscard;
-                        mSentRequest = QUEUED;
-                        mFetcher->addToNetworkQueue(this);
-                        setPriority(LLWorkerThread::PRIORITY_LOW | mWorkPriority);
+                        if(mFetcher->mQueueMutex.tryLock())
+                        {
+                                // Add this to the network queue and sit here.
+                                // LLTextureFetch::update() will send off a request which will change our state
+                                mRequestedSize = mDesiredSize;
+                                mRequestedDiscard = mDesiredDiscard;
+                                mSentRequest = QUEUED;  
+                                mFetcher->addToNetworkQueue(this);
+                                setPriority(LLWorkerThread::PRIORITY_LOW | mWorkPriority);
+                                mFetcher->mQueueMutex.unlock();
+                        }
                         return false;
                 }
                 else
@@ -800,7 +804,7 @@ bool LLTextureFetchWorker::doWork(S32 param)
                         // Set the throttle to the entire bandwidth, assuming UDP packets will get priority
                         // when they are needed
                         F32 max_bandwidth = mFetcher->mMaxBandwidth;
-                        if ((mFetcher->getHTTPQueueSize() >= HTTP_QUEUE_MAX_SIZE) ||
+                        if ((mFetcher->getNumHTTPRequests() >= HTTP_QUEUE_MAX_SIZE) ||
                                 (mFetcher->getTextureBandwidth() > max_bandwidth))
                         {
                                 // Make normal priority and return (i.e. wait until there is room in the queue)
@@ -1469,12 +1473,13 @@ void LLTextureFetch::deleteRequest(const LLUUID& id, bool cancel)
         }
 }
 
+// Need to hold mQueueMutex when entering this function SNOW-196
+// Snowglobe ToDo fix holding mQueueMutex over the entire function, we only need
+// it for the mRequestMap access
 // protected
 void LLTextureFetch::addToNetworkQueue(LLTextureFetchWorker* worker)
 {
-        mQueueMutex.lock();
         bool is_worker_in_request_map = (mRequestMap.find(worker->mID) != mRequestMap.end());
-        mQueueMutex.unlock();
 
         LLMutexLock lock(&mNetworkQueueMutex);
         if (is_worker_in_request_map)
@@ -1916,6 +1921,7 @@ bool LLTextureFetch::receiveImageHeader(const LLHost& host, const LLUUID& id, U8
         {
 //              llwarns << "Received header for non active worker: " << id << llendl;
                 ++mBadPacketCount;
+                LLMutexLock lock2(&mNetworkQueueMutex);
                 mCancelQueue[host].insert(id);
                 return false;
         }
@@ -1944,6 +1950,7 @@ bool LLTextureFetch::receiveImageHeader(const LLHost& host, const LLUUID& id, U8
         if (!res)
         {
                 ++mBadPacketCount;
+                LLMutexLock lock2(&mNetworkQueueMutex);
                 mCancelQueue[host].insert(id);
         }
         else
@@ -1988,6 +1995,7 @@ bool LLTextureFetch::receiveImagePacket(const LLHost& host, const LLUUID& id, U1
         if (!res)
         {
                 ++mBadPacketCount;
+                LLMutexLock lock2(&mNetworkQueueMutex);
                 mCancelQueue[host].insert(id);
                 return false;
         }
diff --git a/linden/indra/newview/lltexturefetch.h b/linden/indra/newview/lltexturefetch.h
index c48f609..5eca0ba 100644
--- a/linden/indra/newview/lltexturefetch.h
+++ b/linden/indra/newview/lltexturefetch.h
@@ -76,8 +76,8 @@ public:
         S32 getFetchState(const LLUUID& id, F32& decode_progress_p, F32& requested_priority_p,
                                           U32& fetch_priority_p, F32& fetch_dtime_p, F32& request_dtime_p);
         void dump();
-        S32 getNumRequests() { return mRequestMap.size(); }
-        S32 getNumHTTPRequests() { return mHTTPTextureQueue.size(); }
+        S32 getNumRequests() const { LLMutexLock lock(&mQueueMutex); return mRequestMap.size(); }
+        S32 getNumHTTPRequests() const { LLMutexLock lock(&mNetworkQueueMutex); return mHTTPTextureQueue.size(); }
         
         // Public for access by callbacks
         void lockQueue() { mQueueMutex.lock(); }
@@ -91,7 +91,6 @@ protected:
         void removeFromNetworkQueue(LLTextureFetchWorker* worker, bool cancel);
         void addToHTTPQueue(const LLUUID& id);
         void removeFromHTTPQueue(const LLUUID& id);
-        S32 getHTTPQueueSize() { return (S32)mHTTPTextureQueue.size(); }
         void removeRequest(LLTextureFetchWorker* worker, bool cancel);
         // Called from worker thread (during doWork)
         void processCurlRequests();     
@@ -110,8 +109,8 @@ public:
         S32 mBadPacketCount;
         
 private:
-        LLMutex mQueueMutex;
-        LLMutex mNetworkQueueMutex;
+        mutable LLMutex mQueueMutex;
+        mutable LLMutex mNetworkQueueMutex;
 
         LLTextureCache* mTextureCache;
         LLImageDecodeThread* mImageDecodeThread;