5 files changed, 116 insertions, 5 deletions

diff --git a/indra/newview/llmeshrepository.cpp b/indra/newview/llmeshrepository.cpp
index 26e2d8f319..2ca94390e5 100644
--- a/indra/newview/llmeshrepository.cpp
+++ b/indra/newview/llmeshrepository.cpp
@@ -3651,20 +3651,95 @@ S32 LLMeshRepository::update()
     return static_cast<S32>(size);
 }
 
-void LLMeshRepository::unregisterMesh(LLVOVolume* vobj)
+#ifdef SHOW_ASSERT
+// Brute-force remove the object from all loading queues. Returns true if
+// something was removed.
+// This function is used in a debug assert to ensure unregisterMesh and
+// unregisterSkinInfo are called as intended.
+// *TODO: Consider removing at some point if we feel confident about the code
+// working as intended.
+bool LLMeshRepository::forceUnregisterMesh(LLVOVolume* vobj)
 {
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_VOLUME;
+
+    bool found = false;
+
     for (auto& lod : mLoadingMeshes)
     {
         for (auto& param : lod)
         {
-            vector_replace_with_last(param.second, vobj);
+            llassert(std::find(param.second.begin(), param.second.end(), vobj) == param.second.end());
+            found = found || vector_replace_with_last(param.second, vobj);
         }
     }
 
     for (auto& skin_pair : mLoadingSkins)
     {
-        vector_replace_with_last(skin_pair.second, vobj);
+        llassert(std::find(skin_pair.second.begin(), skin_pair.second.end(), vobj) == skin_pair.second.end());
+        found = found || vector_replace_with_last(skin_pair.second, vobj);
+    }
+
+    return found;
+}
+#endif
+
+void LLMeshRepository::unregisterMesh(LLVOVolume* vobj, const LLVolumeParams& mesh_params, S32 detail)
+{
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_VOLUME;
+
+    llassert((mesh_params.getSculptType() & LL_SCULPT_TYPE_MASK) == LL_SCULPT_TYPE_MESH);
+    llassert(mesh_params.getSculptID().notNull());
+    auto& lod = mLoadingMeshes[detail];
+    auto param_iter = lod.find(mesh_params.getSculptID());
+    if (param_iter != lod.end())
+    {
+        vector_replace_with_last(param_iter->second, vobj);
+        llassert(!vector_replace_with_last(param_iter->second, vobj));
+        if (param_iter->second.empty())
+        {
+            lod.erase(param_iter);
+        }
+    }
+}
+
+void LLMeshRepository::unregisterSkinInfo(const LLUUID& mesh_id, LLVOVolume* vobj)
+{
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_VOLUME;
+
+    llassert(mesh_id.notNull());
+    auto skin_pair_iter = mLoadingSkins.find(mesh_id);
+    if (skin_pair_iter != mLoadingSkins.end())
+    {
+        vector_replace_with_last(skin_pair_iter->second, vobj);
+        llassert(!vector_replace_with_last(skin_pair_iter->second, vobj));
+        if (skin_pair_iter->second.empty())
+        {
+            mLoadingSkins.erase(skin_pair_iter);
+        }
+    }
+}
+
+// Lots of dead objects make expensive calls to
+// LLMeshRepository::unregisterMesh which may delay shutdown. Avoid this by
+// preemptively unregistering all meshes.
+// We can also do this safely if all objects are confirmed dead for some other
+// reason.
+void LLMeshRepository::unregisterAllMeshes()
+{
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_VOLUME;
+
+    // The size of mLoadingMeshes and mLoadingSkins may be large and thus
+    // expensive to iterate over in LLVOVolume::~LLVOVolume.
+    // This is unnecessary during shutdown, so we ignore the referenced objects in the
+    // least expensive way which is still safe: by clearing these containers.
+    // Clear now and not in LLMeshRepository::shutdown because
+    // LLMeshRepository::notifyLoadedMeshes could (depending on invocation
+    // order) reference a pointer to an object after it has been deleted.
+    for (auto& lod : mLoadingMeshes)
+    {
+        lod.clear();
     }
+    mLoadingSkins.clear();
 }
 
 S32 LLMeshRepository::loadMesh(LLVOVolume* vobj, const LLVolumeParams& mesh_params, S32 detail, S32 last_lod)
diff --git a/indra/newview/llmeshrepository.h b/indra/newview/llmeshrepository.h
index b850ade0bb..b8bec7f233 100644
--- a/indra/newview/llmeshrepository.h
+++ b/indra/newview/llmeshrepository.h
@@ -632,10 +632,15 @@ public:
     LLMeshRepository();
 
     void init();
+    void unregisterAllMeshes();
     void shutdown();
     S32 update();
 
-    void unregisterMesh(LLVOVolume* volume);
+#ifdef SHOW_ASSERT
+    bool forceUnregisterMesh(LLVOVolume* volume);
+#endif
+    void unregisterMesh(LLVOVolume* vobj, const LLVolumeParams& mesh_params, S32 detail);
+    void unregisterSkinInfo(const LLUUID& mesh_id, LLVOVolume* vobj);
     //mesh management functions
     S32 loadMesh(LLVOVolume* volume, const LLVolumeParams& mesh_params, S32 detail = 0, S32 last_lod = -1);
 
diff --git a/indra/newview/llviewerobjectlist.cpp b/indra/newview/llviewerobjectlist.cpp
index 9e1d86faac..6167129077 100644
--- a/indra/newview/llviewerobjectlist.cpp
+++ b/indra/newview/llviewerobjectlist.cpp
@@ -65,6 +65,7 @@
 #include "lltoolmgr.h"
 #include "lltoolpie.h"
 #include "llkeyboard.h"
+#include "llmeshrepository.h"
 #include "u64.h"
 #include "llviewertexturelist.h"
 #include "lldatapacker.h"
@@ -1419,6 +1420,10 @@ void LLViewerObjectList::cleanDeadObjects(bool use_timer)
         // No dead objects, don't need to scan object list.
         return;
     }
+    if ((LLApp::isExiting()) || (mNumDeadObjects == (S32)mObjects.size()))
+    {
+        gMeshRepo.unregisterAllMeshes();
+    }
 
     LL_PROFILE_ZONE_SCOPED;
 
diff --git a/indra/newview/llvovolume.cpp b/indra/newview/llvovolume.cpp
index 7da4358f86..2f2054355a 100644
--- a/indra/newview/llvovolume.cpp
+++ b/indra/newview/llvovolume.cpp
@@ -250,10 +250,13 @@ LLVOVolume::~LLVOVolume()
     delete mVolumeImpl;
     mVolumeImpl = NULL;
 
-    gMeshRepo.unregisterMesh(this);
+    unregisterOldMeshAndSkin();
+    llassert(!gMeshRepo.forceUnregisterMesh(this));
 
     if(!mMediaImplList.empty())
     {
+        LL_PROFILE_ZONE_NAMED_CATEGORY_MEDIA("delete volume media list");
+
         for(U32 i = 0 ; i < mMediaImplList.size() ; i++)
         {
             if(mMediaImplList[i].notNull())
@@ -998,6 +1001,28 @@ LLDrawable *LLVOVolume::createDrawable(LLPipeline *pipeline)
     return mDrawable;
 }
 
+// Inverse of gMeshRepo.loadMesh and gMeshRepo.getSkinInfo, combined into one function
+// Assume a Collada mesh never changes after being set.
+void LLVOVolume::unregisterOldMeshAndSkin()
+{
+    if (mVolumep)
+    {
+        const LLVolumeParams& params = mVolumep->getParams();
+        if ((params.getSculptType() & LL_SCULPT_TYPE_MASK) == LL_SCULPT_TYPE_MESH)
+        {
+            // object is being deleted, so it will no longer need to request
+            // meshes.
+            for (S32 lod = 0; lod != LLVolumeLODGroup::NUM_LODS; ++lod)
+            {
+                gMeshRepo.unregisterMesh(this, params, lod);
+            }
+            // This volume may or may not have a skin
+            gMeshRepo.unregisterSkinInfo(params.getSculptID(), this);
+        }
+    }
+}
+
+
 bool LLVOVolume::setVolume(const LLVolumeParams &params_in, const S32 detail, bool unique_volume)
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_VOLUME;
diff --git a/indra/newview/llvovolume.h b/indra/newview/llvovolume.h
index 6241bf42d6..dfd75aa7d0 100644
--- a/indra/newview/llvovolume.h
+++ b/indra/newview/llvovolume.h
@@ -227,6 +227,7 @@ public:
 
                 void    setTexture(const S32 face);
                 S32     getIndexInTex(U32 ch) const {return mIndexInTex[ch];}
+                void    unregisterOldMeshAndSkin();
     /*virtual*/ bool    setVolume(const LLVolumeParams &volume_params, const S32 detail, bool unique_volume = false) override;
                 void    updateSculptTexture();
                 void    setIndexInTex(U32 ch, S32 index) { mIndexInTex[ch] = index ;}