Merge branch 'project/gltf_development' into 1357-gltf-asset-prototype

30 files changed, 198 insertions, 161 deletions

diff --git a/indra/llcommon/llcommon.cpp b/indra/llcommon/llcommon.cpp
index 6e988260a9..30aefa3134 100644
--- a/indra/llcommon/llcommon.cpp
+++ b/indra/llcommon/llcommon.cpp
@@ -128,8 +128,7 @@ void LLCommon::initClass()
 		sAprInitialized = TRUE;
 	}
 	LLTimer::initClass();
-	LLThreadSafeRefCount::initThreadSafeRefCount();
-	assert_main_thread();		// Make sure we record the main thread
+	assert_main_thread();       // Make sure we record the main thread
 	if (!sMasterThreadRecorder)
 	{
 		sMasterThreadRecorder = new LLTrace::ThreadRecorder();
@@ -143,7 +142,6 @@ void LLCommon::cleanupClass()
 	delete sMasterThreadRecorder;
 	sMasterThreadRecorder = NULL;
 	LLTrace::set_master_thread_recorder(NULL);
-	LLThreadSafeRefCount::cleanupThreadSafeRefCount();
 	SUBSYSTEM_CLEANUP_DBG(LLTimer);
 	if (sAprInitialized)
 	{
diff --git a/indra/llcommon/llcoros.cpp b/indra/llcommon/llcoros.cpp
index c13900f74a..219c65fbb8 100644
--- a/indra/llcommon/llcoros.cpp
+++ b/indra/llcommon/llcoros.cpp
@@ -61,6 +61,23 @@
 #include <excpt.h>
 #endif
 
+// static 
+bool LLCoros::on_main_coro()
+{
+    if (!LLCoros::instanceExists() || LLCoros::getName().empty())
+    {
+        return true;
+    }
+    
+    return false;
+}
+
+// static
+bool LLCoros::on_main_thread_main_coro()
+{
+    return on_main_coro() && on_main_thread();
+}
+
 // static
 LLCoros::CoroData& LLCoros::get_CoroData(const std::string& caller)
 {
diff --git a/indra/llcommon/llcoros.h b/indra/llcommon/llcoros.h
index fd878f20ad..00650a2454 100644
--- a/indra/llcommon/llcoros.h
+++ b/indra/llcommon/llcoros.h
@@ -94,6 +94,16 @@ class LL_COMMON_API LLCoros: public LLSingleton<LLCoros>
 
     void cleanupSingleton() override;
 public:
+    // For debugging, return true if on the main coroutine for the current thread
+    // Code that should not be executed from a coroutine should be protected by
+    // llassert(LLCoros::on_main_coro())
+    static bool on_main_coro();
+
+    // For debugging, return true if on the main thread and not in a coroutine
+    // Non-thread-safe code in the main loop should be protected by 
+    // llassert(LLCoros::on_main_thread_main_coro())
+    static bool on_main_thread_main_coro();
+
     /// The viewer's use of the term "coroutine" became deeply embedded before
     /// the industry term "fiber" emerged to distinguish userland threads from
     /// simpler, more transient kinds of coroutines. Semantically they've
diff --git a/indra/llcommon/llerror.cpp b/indra/llcommon/llerror.cpp
index 0f48ce16b2..74b138a53b 100644
--- a/indra/llcommon/llerror.cpp
+++ b/indra/llcommon/llerror.cpp
@@ -506,7 +506,7 @@ namespace
         LLError::TimeFunction               mTimeFunction;
 
         Recorders                           mRecorders;
-        LLMutex                             mRecorderMutex;
+        LLCoros::Mutex                      mRecorderMutex;
 
         int                                 mShouldLogCallCounter;
 
@@ -1044,7 +1044,7 @@ namespace LLError
 			return;
 		}
 		SettingsConfigPtr s = Globals::getInstance()->getSettingsConfig();
-		LLMutexLock lock(&s->mRecorderMutex);
+		LLCoros::LockType lock(s->mRecorderMutex);
 		s->mRecorders.push_back(recorder);
 	}
 
@@ -1055,7 +1055,7 @@ namespace LLError
 			return;
 		}
 		SettingsConfigPtr s = Globals::getInstance()->getSettingsConfig();
-		LLMutexLock lock(&s->mRecorderMutex);
+		LLCoros::LockType lock(s->mRecorderMutex);
 		s->mRecorders.erase(std::remove(s->mRecorders.begin(), s->mRecorders.end(), recorder),
 							s->mRecorders.end());
 	}
@@ -1104,7 +1104,7 @@ namespace LLError
     std::shared_ptr<RECORDER> findRecorder()
     {
         SettingsConfigPtr s = Globals::getInstance()->getSettingsConfig();
-        LLMutexLock lock(&s->mRecorderMutex);
+        LLCoros::LockType lock(s->mRecorderMutex);
         return findRecorderPos<RECORDER>(s).first;
     }
 
@@ -1115,7 +1115,7 @@ namespace LLError
     bool removeRecorder()
     {
         SettingsConfigPtr s = Globals::getInstance()->getSettingsConfig();
-        LLMutexLock lock(&s->mRecorderMutex);
+        LLCoros::LockType lock(s->mRecorderMutex);
         auto found = findRecorderPos<RECORDER>(s);
         if (found.first)
         {
@@ -1221,7 +1221,7 @@ namespace
 
         std::string escaped_message;
 
-        LLMutexLock lock(&s->mRecorderMutex);
+        LLCoros::LockType lock(s->mRecorderMutex);
 		for (LLError::RecorderPtr& r : s->mRecorders)
 		{
             if (!r->enabled())
diff --git a/indra/llcommon/llevents.cpp b/indra/llcommon/llevents.cpp
index 70931f3a65..8006f9d059 100644
--- a/indra/llcommon/llevents.cpp
+++ b/indra/llcommon/llevents.cpp
@@ -382,7 +382,7 @@ std::string LLEventPump::inventName(const std::string& pfx)
 
 void LLEventPump::clear()
 {
-    LLMutexLock lock(&mConnectionListMutex);
+    LLCoros::LockType lock(mConnectionListMutex);
     // Destroy the original LLStandardSignal instance, replacing it with a
     // whole new one.
     mSignal = std::make_shared<LLStandardSignal>();
@@ -394,7 +394,7 @@ void LLEventPump::reset()
 {
     // Resetting mSignal is supposed to disconnect everything on its own
     // But due to crash on 'reset' added explicit cleanup to get more data
-    LLMutexLock lock(&mConnectionListMutex);
+    LLCoros::LockType lock(mConnectionListMutex);
     ConnectionMap::const_iterator iter = mConnections.begin();
     ConnectionMap::const_iterator end = mConnections.end();
     while (iter!=end)
@@ -419,7 +419,7 @@ LLBoundListener LLEventPump::listen_impl(const std::string& name, const LLEventL
         return LLBoundListener();
     }
 
-    LLMutexLock lock(&mConnectionListMutex);
+    LLCoros::LockType lock(mConnectionListMutex);
 
     float nodePosition = 1.0;
 
@@ -582,7 +582,7 @@ LLBoundListener LLEventPump::listen_impl(const std::string& name, const LLEventL
 
 LLBoundListener LLEventPump::getListener(const std::string& name)
 {
-    LLMutexLock lock(&mConnectionListMutex);
+    LLCoros::LockType lock(mConnectionListMutex);
     ConnectionMap::const_iterator found = mConnections.find(name);
     if (found != mConnections.end())
     {
@@ -594,7 +594,7 @@ LLBoundListener LLEventPump::getListener(const std::string& name)
 
 void LLEventPump::stopListening(const std::string& name)
 {
-    LLMutexLock lock(&mConnectionListMutex);
+    LLCoros::LockType lock(mConnectionListMutex);
     ConnectionMap::iterator found = mConnections.find(name);
     if (found != mConnections.end())
     {
diff --git a/indra/llcommon/llevents.h b/indra/llcommon/llevents.h
index bebcfacdcb..df54a6546d 100644
--- a/indra/llcommon/llevents.h
+++ b/indra/llcommon/llevents.h
@@ -61,6 +61,7 @@
 #include "llstl.h"
 #include "llexception.h"
 #include "llhandle.h"
+#include "llcoros.h"
 
 /*==========================================================================*|
 // override this to allow binding free functions with more parameters
@@ -601,7 +602,7 @@ private:
     LLHandle<LLEventPumps> mRegistry;
 
     std::string mName;
-    LLMutex mConnectionListMutex;
+    LLCoros::Mutex mConnectionListMutex;
 
 protected:
     virtual LLBoundListener listen_impl(const std::string& name, const LLEventListener&,
diff --git a/indra/llcommon/llfixedbuffer.h b/indra/llcommon/llfixedbuffer.h
index 554cf48a4c..b3bef7520b 100644
--- a/indra/llcommon/llfixedbuffer.h
+++ b/indra/llcommon/llfixedbuffer.h
@@ -33,6 +33,7 @@
 #include "llstring.h"
 #include "llthread.h"
 #include "llerrorcontrol.h"
+#include "llcoros.h"
 
 //  fixed buffer implementation
 class LL_COMMON_API LLFixedBuffer : public LLLineBuffer
@@ -58,7 +59,7 @@ protected:
 	void addWLine(const LLWString& line);
 
 protected:
-	LLMutex mMutex ;
+	LLCoros::Mutex mMutex ;
 };
 
 #endif //LL_FIXED_BUFFER_H
diff --git a/indra/llcommon/llmutex.cpp b/indra/llcommon/llmutex.cpp
index 0273dd5970..5d93d6e72b 100644
--- a/indra/llcommon/llmutex.cpp
+++ b/indra/llcommon/llmutex.cpp
@@ -28,6 +28,7 @@
 #include "llmutex.h"
 #include "llthread.h"
 #include "lltimer.h"
+#include "llcoros.h"
 
 //============================================================================
 
@@ -44,7 +45,17 @@ LLMutex::~LLMutex()
 
 void LLMutex::lock()
 {
-    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD;
+
+    // LLMutex is not coroutine aware and should not be used from a coroutine
+    // If your code is running in a coroutine, you should use LLCoros::Mutex instead
+    // NOTE:  If the stack trace you're staring at contains non-thread-safe code,
+    // you should use LLAppViewer::instance().postToMainThread() to shuttle execution
+    // back to the main loop.
+    // NOTE: If you got here from seeing this assert in your log and you're not seeing
+    // a stack trace that points here, put a breakpoint in on_main_coro and try again.
+    llassert(LLCoros::on_main_coro());
+
 	if(isSelfLocked())
 	{ //redundant lock
 		mCount++;
@@ -66,7 +77,8 @@ void LLMutex::lock()
 
 void LLMutex::unlock()
 {
-    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD;
+
 	if (mCount > 0)
 	{ //not the root unlock
 		mCount--;
@@ -111,7 +123,7 @@ LLThread::id_t LLMutex::lockingThread() const
 
 bool LLMutex::trylock()
 {
-    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_THREAD;
 	if(isSelfLocked())
 	{ //redundant lock
 		mCount++;
diff --git a/indra/llcommon/llrefcount.h b/indra/llcommon/llrefcount.h
index 15e7175fc8..109c29c0c9 100644
--- a/indra/llcommon/llrefcount.h
+++ b/indra/llcommon/llrefcount.h
@@ -89,13 +89,6 @@ private:
 
 class LL_COMMON_API LLThreadSafeRefCount
 {
-public:
-	static void initThreadSafeRefCount(); // creates sMutex
-	static void cleanupThreadSafeRefCount(); // destroys sMutex
-
-private:
-	static LLMutex* sMutex;
-
 protected:
 	virtual ~LLThreadSafeRefCount(); // use unref()
 
diff --git a/indra/llcommon/llthread.cpp b/indra/llcommon/llthread.cpp
index cd4975d9d3..ef66c36827 100644
--- a/indra/llcommon/llthread.cpp
+++ b/indra/llcommon/llthread.cpp
@@ -421,30 +421,6 @@ void LLThread::unlockData()
 
 //============================================================================
 
-//----------------------------------------------------------------------------
-
-//static
-LLMutex* LLThreadSafeRefCount::sMutex = 0;
-
-//static
-void LLThreadSafeRefCount::initThreadSafeRefCount()
-{
-    if (!sMutex)
-    {
-        sMutex = new LLMutex();
-    }
-}
-
-//static
-void LLThreadSafeRefCount::cleanupThreadSafeRefCount()
-{
-    delete sMutex;
-    sMutex = NULL;
-}
-    
-
-//----------------------------------------------------------------------------
-
 LLThreadSafeRefCount::LLThreadSafeRefCount() :
     mRef(0)
 {
diff --git a/indra/llmessage/llavatarnamecache.cpp b/indra/llmessage/llavatarnamecache.cpp
index f7a9f55685..314e7f0217 100644
--- a/indra/llmessage/llavatarnamecache.cpp
+++ b/indra/llmessage/llavatarnamecache.cpp
@@ -45,6 +45,7 @@
 #include "llcorehttputil.h"
 #include "llexception.h"
 #include "stringize.h"
+#include "workqueue.h"
 
 #include <map>
 #include <set>
@@ -179,19 +180,26 @@ void LLAvatarNameCache::requestAvatarNameCache_(std::string url, std::vector<LLU
 
         if (LLAvatarNameCache::instanceExists())
         {
-            if (!success)
-            {   // on any sort of failure add dummy records for any agent IDs 
-                // in this request that we do not have cached already
-                std::vector<LLUUID>::const_iterator it = agentIds.begin();
-                for (; it != agentIds.end(); ++it)
-                {
-                    const LLUUID& agent_id = *it;
-                    LLAvatarNameCache::getInstance()->handleAgentError(agent_id);
-                }
-                return;
-            }
+            // dispatch handler execution back to mainloop
+            auto workqueue = LL::WorkQueue::getInstance("mainloop");
 
-            LLAvatarNameCache::getInstance()->handleAvNameCacheSuccess(results, httpResults);
+            if (workqueue)
+            {
+                workqueue->post([=]()
+                    {
+                        if (!success)
+                        {   // on any sort of failure add dummy records for any agent IDs 
+                            // in this request that we do not have cached already
+                            for (const auto& agent_id : agentIds)
+                            {
+                                LLAvatarNameCache::getInstance()->handleAgentError(agent_id);
+                            }
+                            return;
+                        }
+
+                        LLAvatarNameCache::getInstance()->handleAvNameCacheSuccess(results, httpResults);
+                    });
+            }
         }
     }
     catch (const LLCoros::Stop&)
diff --git a/indra/llplugin/llpluginprocessparent.cpp b/indra/llplugin/llpluginprocessparent.cpp
index f5966b71de..a28f6c648f 100644
--- a/indra/llplugin/llpluginprocessparent.cpp
+++ b/indra/llplugin/llpluginprocessparent.cpp
@@ -34,7 +34,6 @@
 #include "llpluginmessageclasses.h"
 #include "llsdserialize.h"
 #include "stringize.h"
-
 #include "llapr.h"
 
 //virtual 
@@ -46,7 +45,7 @@ LLPluginProcessParentOwner::~LLPluginProcessParentOwner()
 bool LLPluginProcessParent::sUseReadThread = false;
 apr_pollset_t *LLPluginProcessParent::sPollSet = NULL;
 bool LLPluginProcessParent::sPollsetNeedsRebuild = false;
-LLMutex *LLPluginProcessParent::sInstancesMutex;
+LLCoros::Mutex *LLPluginProcessParent::sInstancesMutex;
 LLPluginProcessParent::mapInstances_t LLPluginProcessParent::sInstances;
 LLThread *LLPluginProcessParent::sReadThread = NULL;
 
@@ -106,7 +105,7 @@ LLPluginProcessParent::LLPluginProcessParent(LLPluginProcessParentOwner *owner):
 {
 	if(!sInstancesMutex)
 	{
-		sInstancesMutex = new LLMutex();
+		sInstancesMutex = new LLCoros::Mutex();
 	}
 	
 	mOwner = owner;
@@ -176,7 +175,7 @@ LLPluginProcessParent::ptr_t LLPluginProcessParent::create(LLPluginProcessParent
 
     // Don't add to the global list until fully constructed.
     {
-        LLMutexLock lock(sInstancesMutex);
+        LLCoros::LockType lock(*sInstancesMutex);
         sInstances.insert(mapInstances_t::value_type(that.get(), that));
     }
 
@@ -186,7 +185,7 @@ LLPluginProcessParent::ptr_t LLPluginProcessParent::create(LLPluginProcessParent
 /*static*/
 void LLPluginProcessParent::shutdown()
 {
-    LLMutexLock lock(sInstancesMutex);
+    LLCoros::LockType lock(*sInstancesMutex);
 
     mapInstances_t::iterator it;
     for (it = sInstances.begin(); it != sInstances.end(); ++it)
@@ -244,7 +243,7 @@ bool LLPluginProcessParent::pollTick()
         {
             // this grabs a copy of the smart pointer to ourselves to ensure that we do not
             // get destroyed until after this method returns.
-            LLMutexLock lock(sInstancesMutex);
+            LLCoros::LockType lock(*sInstancesMutex);
             mapInstances_t::iterator it = sInstances.find(this);
             if (it != sInstances.end())
                 that = (*it).second;
@@ -263,7 +262,7 @@ void LLPluginProcessParent::removeFromProcessing()
     // Remove from the global list before beginning destruction.
     {
         // Make sure to get the global mutex _first_ here, to avoid a possible deadlock against LLPluginProcessParent::poll()
-        LLMutexLock lock(sInstancesMutex);
+        LLCoros::LockType lock(*sInstancesMutex);
         {
             LLMutexLock lock2(&mIncomingQueueMutex);
             sInstances.erase(this);
@@ -845,7 +844,7 @@ void LLPluginProcessParent::updatePollset()
 		return;
 	}
 		
-	LLMutexLock lock(sInstancesMutex);
+    LLCoros::LockType lock(*sInstancesMutex);
 
 	if(sPollSet)
 	{
@@ -968,7 +967,7 @@ void LLPluginProcessParent::poll(F64 timeout)
                 mapInstances_t::iterator it;
 
                 {
-                    LLMutexLock lock(sInstancesMutex);
+                    LLCoros::LockType lock(*sInstancesMutex);
                     it = sInstances.find(thatId);
                     if (it != sInstances.end())
                         that = (*it).second;
diff --git a/indra/llplugin/llpluginprocessparent.h b/indra/llplugin/llpluginprocessparent.h
index 01627925d7..2f9dc921ea 100644
--- a/indra/llplugin/llpluginprocessparent.h
+++ b/indra/llplugin/llpluginprocessparent.h
@@ -207,7 +207,7 @@ private:
 	apr_pollfd_t mPollFD;
 	static apr_pollset_t *sPollSet;
 	static bool sPollsetNeedsRebuild;
-	static LLMutex *sInstancesMutex;
+	static LLCoros::Mutex *sInstancesMutex;
     static mapInstances_t sInstances;
 	static void dirtyPollSet();
 	static void updatePollset();
diff --git a/indra/llrender/llshadermgr.cpp b/indra/llrender/llshadermgr.cpp
index 0b20ff6230..636e13719a 100644
--- a/indra/llrender/llshadermgr.cpp
+++ b/indra/llrender/llshadermgr.cpp
@@ -328,7 +328,7 @@ BOOL LLShaderMgr::attachShaderFeatures(LLGLSLShader * shader)
 					return FALSE;
 				}
 			}
-			shader->mFeatures.mIndexedTextureChannels = llmax(LLGLSLShader::sIndexedTextureChannels-1, 1);
+			shader->mFeatures.mIndexedTextureChannels = llmax(LLGLSLShader::sIndexedTextureChannels, 1);
 		}
 	}
 	
diff --git a/indra/llui/llconsole.cpp b/indra/llui/llconsole.cpp
index 8fc2978bdd..6a44108741 100644
--- a/indra/llui/llconsole.cpp
+++ b/indra/llui/llconsole.cpp
@@ -380,7 +380,7 @@ void LLConsole::updateClass()
 void LLConsole::update()
 {
 	{
-		LLMutexLock lock(&mMutex);
+		LLCoros::LockType lock(mMutex);
 
 		while (!mLines.empty())
 		{
diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index e42906e78b..e1eeefa755 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -10712,38 +10712,49 @@
     <integer>3</integer>
   </map>
   <key>RenderReflectionRes</key>
-    <map>
-      <key>Comment</key>
-      <string>Reflection map resolution.</string>
-      <key>Persist</key>
-      <integer>1</integer>
-      <key>Type</key>
-      <string>S32</string>
-      <key>Value</key>
-      <integer>64</integer>
-    </map>
-    <key>RenderResolutionDivisor</key>
-    <map>
-      <key>Comment</key>
-      <string>Divisor for rendering 3D scene at reduced resolution.</string>
-      <key>Persist</key>
-      <integer>1</integer>
-      <key>Type</key>
-      <string>U32</string>
-      <key>Value</key>
-      <integer>1</integer>
-    </map>
-    <key>RenderShaderLightingMaxLevel</key>
-    <map>
-      <key>Comment</key>
-      <string>Max lighting level to use in the shader (class 3 is default, 2 is less lights, 1 is sun/moon only.  Works around shader compiler bugs on certain platforms.)</string>
-      <key>Persist</key>
-      <integer>1</integer>
-      <key>Type</key>
-      <string>S32</string>
-      <key>Value</key>
-      <integer>3</integer>
-    </map>
+  <map>
+    <key>Comment</key>
+    <string>Reflection map resolution.</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>S32</string>
+    <key>Value</key>
+    <integer>64</integer>
+  </map>
+  <key>RenderReservedTextureIndices</key>
+  <map>
+    <key>Comment</key>
+    <string>Count of texture indices to reserve for shadow and reflection maps when using indexed texture rendering.  Probably only want to set from the login screen.</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>S32</string>
+    <key>Value</key>
+    <integer>14</integer>
+  </map>
+  <key>RenderResolutionDivisor</key>
+  <map>
+    <key>Comment</key>
+    <string>Divisor for rendering 3D scene at reduced resolution.</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>U32</string>
+    <key>Value</key>
+    <integer>1</integer>
+  </map>
+  <key>RenderShaderLightingMaxLevel</key>
+  <map>
+    <key>Comment</key>
+    <string>Max lighting level to use in the shader (class 3 is default, 2 is less lights, 1 is sun/moon only.  Works around shader compiler bugs on certain platforms.)</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>S32</string>
+    <key>Value</key>
+    <integer>3</integer>
+  </map>
   <key>RenderSkyAutoAdjustLegacy</key>
   <map>
     <key>Comment</key>
diff --git a/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl b/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
index 183354b9bd..6ef556d7e8 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
@@ -55,7 +55,7 @@ void main()
 
     frag_data[0] = vec4(0);
     frag_data[1] = vec4(0.0);
-    frag_data[2] = vec4(0.0, 0.0, 0.0, GBUFFER_FLAG_HAS_ATMOS);
+    frag_data[2] = vec4(0.0, 0.0, 0.0, GBUFFER_FLAG_SKIP_ATMOS);
     frag_data[3] = vec4(c.rgb, c.a);
 
     // Added and commented out for a ground truth.  Do not uncomment - Geenz
diff --git a/indra/newview/llappviewer.cpp b/indra/newview/llappviewer.cpp
index 90f9b38f2d..c966f9cbcc 100644
--- a/indra/newview/llappviewer.cpp
+++ b/indra/newview/llappviewer.cpp
@@ -5200,6 +5200,11 @@ void LLAppViewer::updateNameLookupUrl(const LLViewerRegion * regionp)
     }
 }
 
+void LLAppViewer::postToMainCoro(const LL::WorkQueue::Work& work)
+{
+    gMainloopWork.post(work);
+}
+
 void LLAppViewer::idleNameCache()
 {
 	// Neither old nor new name cache can function before agent has a region
diff --git a/indra/newview/llappviewer.h b/indra/newview/llappviewer.h
index 9352dba06d..92976a70af 100644
--- a/indra/newview/llappviewer.h
+++ b/indra/newview/llappviewer.h
@@ -226,6 +226,9 @@ public:
 
 	void updateNameLookupUrl(const LLViewerRegion* regionp);
 
+    // post given work to the "mainloop" work queue for handling on the main thread
+    void postToMainCoro(const LL::WorkQueue::Work& work);
+
 protected:
 	virtual bool initWindow(); // Initialize the viewer's window.
 	virtual void initLoggingAndGetLastDuration(); // Initialize log files, logging system
diff --git a/indra/newview/llavatarrenderinfoaccountant.cpp b/indra/newview/llavatarrenderinfoaccountant.cpp
index b95b971890..ba9ba4dc64 100644
--- a/indra/newview/llavatarrenderinfoaccountant.cpp
+++ b/indra/newview/llavatarrenderinfoaccountant.cpp
@@ -236,8 +236,6 @@ void LLAvatarRenderInfoAccountant::avatarRenderInfoReportCoro(std::string url, U
             !avatar->isControlAvatar() &&						// Not part of an animated object
             avatar->getObjectHost() == regionp->getHost())		// Ensure it's on the same region
         {
-            avatar->calculateUpdateRenderComplexity();			// Make sure the numbers are up-to-date
-
             LLSD info = LLSD::emptyMap();
             U32 avatar_complexity = avatar->getVisualComplexity();
             if (avatar_complexity > 0)
diff --git a/indra/newview/lldrawpoolalpha.cpp b/indra/newview/lldrawpoolalpha.cpp
index 9418cead76..fd27010877 100644
--- a/indra/newview/lldrawpoolalpha.cpp
+++ b/indra/newview/lldrawpoolalpha.cpp
@@ -478,7 +478,7 @@ bool LLDrawPoolAlpha::TexSetup(LLDrawInfo* draw, bool use_material)
             }
         }
     }
-    
+
     return tex_setup;
 }
 
@@ -668,7 +668,7 @@ void LLDrawPoolAlpha::renderAlpha(U32 mask, bool depth_only, bool rigged)
 
 			LLSpatialGroup::drawmap_elem_t& draw_info = rigged ? group->mDrawMap[LLRenderPass::PASS_ALPHA_RIGGED] : group->mDrawMap[LLRenderPass::PASS_ALPHA];
 
-            for (LLSpatialGroup::drawmap_elem_t::iterator k = draw_info.begin(); k != draw_info.end(); ++k)	
+            for (LLSpatialGroup::drawmap_elem_t::iterator k = draw_info.begin(); k != draw_info.end(); ++k)
 			{
 				LLDrawInfo& params = **k;
                 if ((bool)params.mAvatar != rigged)
@@ -814,9 +814,10 @@ void LLDrawPoolAlpha::renderAlpha(U32 mask, bool depth_only, bool rigged)
                         current_shader->setMinimumAlpha(0.f);
                         reset_minimum_alpha = true;
                     }
-                    
+
                     params.mVertexBuffer->setBuffer();
                     params.mVertexBuffer->drawRange(LLRender::TRIANGLES, params.mStart, params.mEnd, params.mCount, params.mOffset);
+                    stop_glerror();
 
                     if (reset_minimum_alpha)
                     {
diff --git a/indra/newview/lldrawpoolbump.cpp b/indra/newview/lldrawpoolbump.cpp
index 24df11c158..518310476b 100644
--- a/indra/newview/lldrawpoolbump.cpp
+++ b/indra/newview/lldrawpoolbump.cpp
@@ -699,6 +699,8 @@ void LLBumpImageList::addTextureStats(U8 bump, const LLUUID& base_image_id, F32
 
 void LLBumpImageList::updateImages()
 {	
+    llassert(LLCoros::on_main_thread_main_coro()); // This code is not thread safe
+
 	for (bump_image_map_t::iterator iter = mBrightnessEntries.begin(); iter != mBrightnessEntries.end(); )
 	{
 		LLViewerTexture* image = iter->second;
diff --git a/indra/newview/llface.cpp b/indra/newview/llface.cpp
index 69e43bb458..ccee57cf69 100644
--- a/indra/newview/llface.cpp
+++ b/indra/newview/llface.cpp
@@ -1855,7 +1855,7 @@ BOOL LLFace::getGeometryVolume(const LLVolume& volume,
 			S32* vp = (S32*) &val;
 			*vp = index;
 			
-			llassert(index <= LLGLSLShader::sIndexedTextureChannels-1);
+			llassert(index < LLGLSLShader::sIndexedTextureChannels);
 
 			LLVector4Logical mask;
 			mask.clear();
diff --git a/indra/newview/llstartup.cpp b/indra/newview/llstartup.cpp
index a0324ca82a..486b652f07 100644
--- a/indra/newview/llstartup.cpp
+++ b/indra/newview/llstartup.cpp
@@ -334,10 +334,18 @@ void update_texture_fetch()
 
 void set_flags_and_update_appearance()
 {
-	LLAppearanceMgr::instance().setAttachmentInvLinkEnable(true);
-	LLAppearanceMgr::instance().updateAppearanceFromCOF(true, true, no_op);
+    // this may be called from a coroutine but has many side effects
+    // in non-thread-safe classes, post to main loop
+    auto work = []()
+        {
+            LLAppearanceMgr::instance().setAttachmentInvLinkEnable(true);
+            LLAppearanceMgr::instance().updateAppearanceFromCOF(true, true, no_op);
+
+            LLInventoryModelBackgroundFetch::instance().start();
+        };
+
+    LLAppViewer::instance()->postToMainCoro(work);
 
-    LLInventoryModelBackgroundFetch::instance().start();
 }
 
 // Returns false to skip other idle processing. Should only return
diff --git a/indra/newview/llviewermedia.cpp b/indra/newview/llviewermedia.cpp
index 02108e861a..85891744ef 100644
--- a/indra/newview/llviewermedia.cpp
+++ b/indra/newview/llviewermedia.cpp
@@ -1667,7 +1667,7 @@ void LLViewerMediaImpl::destroyMediaSource()
 	cancelMimeTypeProbe();
 
     {
-        LLMutexLock lock(&mLock); // Delay tear-down while bg thread is updating
+        LLCoros::LockType lock(mLock); // Delay tear-down while bg thread is updating
         if(mMediaSource)
         {
             mMediaSource->setDeleteOK(true) ;
@@ -2968,7 +2968,7 @@ bool LLViewerMediaImpl::preMediaTexUpdate(LLViewerMediaTexture*& media_tex, U8*&
 void LLViewerMediaImpl::doMediaTexUpdate(LLViewerMediaTexture* media_tex, U8* data, S32 data_width, S32 data_height, S32 x_pos, S32 y_pos, S32 width, S32 height, bool sync)
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_MEDIA;
-    LLMutexLock lock(&mLock); // don't allow media source tear-down during update
+    LLCoros::LockType lock(mLock); // don't allow media source tear-down during update
 
     // wrap "data" in an LLImageRaw but do NOT make a copy
     LLPointer<LLImageRaw> raw = new LLImageRaw(data, media_tex->getWidth(), media_tex->getHeight(), media_tex->getComponents(), true);
diff --git a/indra/newview/llviewermedia.h b/indra/newview/llviewermedia.h
index 03899b6b8f..378297bf91 100644
--- a/indra/newview/llviewermedia.h
+++ b/indra/newview/llviewermedia.h
@@ -182,7 +182,7 @@ private:
 
 // Implementation functions not exported into header file
 class LLViewerMediaImpl
-	:	public LLMouseHandler, public LLRefCount, public LLPluginClassMediaOwner, public LLViewerMediaEventEmitter, public LLEditMenuHandler
+	:	public LLMouseHandler, public LLThreadSafeRefCount, public LLPluginClassMediaOwner, public LLViewerMediaEventEmitter, public LLEditMenuHandler
 {
 	LOG_CLASS(LLViewerMediaImpl);
 public:
@@ -432,7 +432,7 @@ private:
 private:
 	// a single media url with some data and an impl.
 	std::shared_ptr<LLPluginClassMedia> mMediaSource;
-    LLMutex mLock;
+    LLCoros::Mutex mLock;
 	F64		mZoomFactor;
 	LLUUID mTextureId;
 	bool  mMovieImageHasMips;
diff --git a/indra/newview/llviewerregion.cpp b/indra/newview/llviewerregion.cpp
index 29dce088f5..210d5f84bd 100755
--- a/indra/newview/llviewerregion.cpp
+++ b/indra/newview/llviewerregion.cpp
@@ -2498,11 +2498,8 @@ void LLViewerRegion::setSimulatorFeatures(const LLSD& sim_features)
             }
         };
 
-    auto workqueue = LL::WorkQueue::getInstance("mainloop");
-    if (workqueue)
-    {
-        LL::WorkQueue::postMaybe(workqueue, work);
-    }
+
+    LLAppViewer::instance()->postToMainCoro(work);
 }
 
 //this is called when the parent is not cacheable.
diff --git a/indra/newview/llviewershadermgr.cpp b/indra/newview/llviewershadermgr.cpp
index 289c0d7567..5144b28ce9 100644
--- a/indra/newview/llviewershadermgr.cpp
+++ b/indra/newview/llviewershadermgr.cpp
@@ -423,7 +423,10 @@ void LLViewerShaderMgr::setShaders()
     static LLCachedControl<U32> max_texture_index(gSavedSettings, "RenderMaxTextureIndex", 16);
     
     // when using indexed texture rendering, leave some texture units available for shadow and reflection maps
-    LLGLSLShader::sIndexedTextureChannels = llmax(llmin(gGLManager.mNumTextureImageUnits-12, (S32) max_texture_index), 1);
+    static LLCachedControl<S32> reserved_texture_units(gSavedSettings, "RenderReservedTextureIndices", 14);
+
+    LLGLSLShader::sIndexedTextureChannels =
+        llclamp<S32>(max_texture_index, 1, gGLManager.mNumTextureImageUnits-reserved_texture_units);
 
     reentrance = true;
 
diff --git a/indra/newview/llvoicevivox.cpp b/indra/newview/llvoicevivox.cpp
index 310c9ee297..9a0aae944c 100644
--- a/indra/newview/llvoicevivox.cpp
+++ b/indra/newview/llvoicevivox.cpp
@@ -6437,37 +6437,43 @@ void LLVivoxVoiceClient::notifyStatusObservers(LLVoiceClientStatusObserver::ESta
 			}
 		}
 	}
-		
+	
 	LL_DEBUGS("Voice") 
 		<< " " << LLVoiceClientStatusObserver::status2string(status)  
 		<< ", session URI " << getAudioSessionURI() 
 		<< ", proximal is " << inSpatialChannel()
         << LL_ENDL;
 
-	for (status_observer_set_t::iterator it = mStatusObservers.begin();
-		it != mStatusObservers.end();
-		)
-	{
-		LLVoiceClientStatusObserver* observer = *it;
-		observer->onChange(status, getAudioSessionURI(), inSpatialChannel());
-		// In case onError() deleted an entry.
-		it = mStatusObservers.upper_bound(observer);
-	}
+    // this function is called from a coroutine, shuttle application hook back to main loop
+    auto work = [=]()
+        {
+            for (status_observer_set_t::iterator it = mStatusObservers.begin();
+                it != mStatusObservers.end();
+                )
+            {
+                LLVoiceClientStatusObserver* observer = *it;
+                observer->onChange(status, getAudioSessionURI(), inSpatialChannel());
+                // In case onError() deleted an entry.
+                it = mStatusObservers.upper_bound(observer);
+            }
 
-	// skipped to avoid speak button blinking
-	if (   status != LLVoiceClientStatusObserver::STATUS_JOINING
-		&& status != LLVoiceClientStatusObserver::STATUS_LEFT_CHANNEL
-		&& status != LLVoiceClientStatusObserver::STATUS_VOICE_DISABLED)
-	{
-		bool voice_status = LLVoiceClient::getInstance()->voiceEnabled() && LLVoiceClient::getInstance()->isVoiceWorking();
+            // skipped to avoid speak button blinking
+            if (status != LLVoiceClientStatusObserver::STATUS_JOINING
+                && status != LLVoiceClientStatusObserver::STATUS_LEFT_CHANNEL
+                && status != LLVoiceClientStatusObserver::STATUS_VOICE_DISABLED)
+            {
+                bool voice_status = LLVoiceClient::getInstance()->voiceEnabled() && LLVoiceClient::getInstance()->isVoiceWorking();
 
-		gAgent.setVoiceConnected(voice_status);
+                gAgent.setVoiceConnected(voice_status);
 
-		if (voice_status)
-		{
-			LLFirstUse::speak(true);
-		}
-	}
+                if (voice_status)
+                {
+                    LLFirstUse::speak(true);
+                }
+            }
+        };
+
+    LLAppViewer::instance()->postToMainCoro(work);
 }
 
 void LLVivoxVoiceClient::addObserver(LLFriendObserver* observer)
diff --git a/indra/newview/llvovolume.cpp b/indra/newview/llvovolume.cpp
index b886b922de..1b816b88fb 100644
--- a/indra/newview/llvovolume.cpp
+++ b/indra/newview/llvovolume.cpp
@@ -6248,19 +6248,7 @@ U32 LLVolumeGeometryManager::genDrawInfo(LLSpatialGroup* group, U32 mask, LLFace
 
 	LLViewerTexture* last_tex = NULL;
 
-	S32 texture_index_channels = 1;
-	
-	if (gGLManager.mGLSLVersionMajor > 1 || gGLManager.mGLSLVersionMinor >= 30)
-	{
-		texture_index_channels = LLGLSLShader::sIndexedTextureChannels-1; //always reserve one for shiny for now just for simplicity;
-	}
-
-	if (distance_sort)
-	{
-		texture_index_channels = gDeferredAlphaProgram.mFeatures.mIndexedTextureChannels;
-	}
-
-	texture_index_channels = LLGLSLShader::sIndexedTextureChannels;
+	S32 texture_index_channels = LLGLSLShader::sIndexedTextureChannels;
 
 	bool flexi = false;