Revert of Fix bug in plot locking system

src/gpu/GrLayerCache.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrAtlas.h"
 #include "GrGpu.h"
 #include "GrLayerCache.h"
@@ skipping 135 matching lines @@
     }
 
     return layer;
 }
 
 bool GrLayerCache::lock(GrCachedLayer* layer, const GrTextureDesc& desc, bool dontAtlas) {
     SkDEBUGCODE(GrAutoValidateLayer avl(fAtlas->getTexture(), layer);)
 
     if (layer->locked()) {
         // This layer is already locked
+#ifdef SK_DEBUG
         if (layer->isAtlased()) {
-            this->incPlotLock(layer->plot()->id());
+            // It claims to be atlased
             SkASSERT(!dontAtlas);
             SkASSERT(layer->rect().width() == desc.fWidth);
             SkASSERT(layer->rect().height() == desc.fHeight);
         }
+#endif
         return false;
     }
 
     if (layer->isAtlased()) {
         // Hooray it is still in the atlas - make sure it stays there
         SkASSERT(!dontAtlas);
         layer->setLocked(true);
-        this->incPlotLock(layer->plot()->id());
+        fPlotLocks[layer->plot()->id()]++;
         return false;
     } else if (!dontAtlas && PlausiblyAtlasable(desc.fWidth, desc.fHeight)) {
         // Not in the atlas - will it fit?
         GrPictureInfo* pictInfo = fPictureHash.find(layer->pictureID());
         if (NULL == pictInfo) {
             pictInfo = SkNEW_ARGS(GrPictureInfo, (layer->pictureID()));
             fPictureHash.add(pictInfo);
         }
 
         SkIPoint16 loc;
         for (int i = 0; i < 2; ++i) { // extra pass in case we fail to add but are able to purge
             GrPlot* plot = fAtlas->addToAtlas(&pictInfo->fPlotUsage,
                                               desc.fWidth, desc.fHeight,
                                               NULL, &loc);
             // addToAtlas can allocate the backing texture
             SkDEBUGCODE(avl.setBackingTexture(fAtlas->getTexture()));
             if (plot) {
                 // The layer was successfully added to the atlas
                 GrIRect16 bounds = GrIRect16::MakeXYWH(loc.fX, loc.fY,
                                                        SkToS16(desc.fWidth),
                                                        SkToS16(desc.fHeight));
                 layer->setTexture(fAtlas->getTexture(), bounds);
                 layer->setPlot(plot);
                 layer->setLocked(true);
-                this->incPlotLock(layer->plot()->id());
+                fPlotLocks[layer->plot()->id()]++;
                 return true;
             }
 
             // The layer was rejected by the atlas (even though we know it is 
             // plausibly atlas-able). See if a plot can be purged and try again.
             if (!this->purgePlot()) {
                 break;  // We weren't able to purge any plots
             }
         }
     }
 
     // The texture wouldn't fit in the cache - give it it's own texture.
     // This path always uses a new scratch texture and (thus) doesn't cache anything.
     // This can yield a lot of re-rendering
     SkAutoTUnref<GrTexture> tex(fContext->lockAndRefScratchTexture(desc,
                                                         GrContext::kApprox_ScratchTexMatch));
 
     layer->setTexture(tex, GrIRect16::MakeWH(SkToS16(desc.fWidth), SkToS16(desc.fHeight)));
     layer->setLocked(true);
     return true;
 }
 
 void GrLayerCache::unlock(GrCachedLayer* layer) {
     SkDEBUGCODE(GrAutoValidateLayer avl(fAtlas->getTexture(), layer);)
 
-    if (NULL == layer) {
+    if (NULL == layer || !layer->locked()) {
         // invalid or not locked
         return;
     }
 
     if (layer->isAtlased()) {
         const int plotID = layer->plot()->id();
 
-        this->decPlotLock(plotID);
+        SkASSERT(fPlotLocks[plotID] > 0);
+        fPlotLocks[plotID]--;
         // At this point we could aggressively clear out un-locked plots but
         // by delaying we may be able to reuse some of the atlased layers later.
 #if DISABLE_CACHING
         // This testing code aggressively removes the atlased layers. This
         // can be used to separate the performance contribution of less
         // render target pingponging from that due to the re-use of cached layers
         GrPictureInfo* pictInfo = fPictureHash.find(layer->pictureID());
         SkASSERT(pictInfo);
         
         GrAtlas::RemovePlot(&pictInfo->fPlotUsage, layer->plot());
         
         layer->setPlot(NULL);
         layer->setTexture(NULL, GrIRect16::MakeEmpty());
 #endif
 
     } else {
         layer->setTexture(NULL, GrIRect16::MakeEmpty());
     }
 
     layer->setLocked(false);
 }
 
 #ifdef SK_DEBUG
 void GrLayerCache::validate() const {
+    int plotLocks[kNumPlotsX * kNumPlotsY];
+    memset(plotLocks, 0, sizeof(plotLocks));
+
     SkTDynamicHash<GrCachedLayer, GrCachedLayer::Key>::ConstIter iter(&fLayerHash);
     for (; !iter.done(); ++iter) {
         const GrCachedLayer* layer = &(*iter);
 
         layer->validate(fAtlas->getTexture());
 
         const GrPictureInfo* pictInfo = fPictureHash.find(layer->pictureID());
         if (pictInfo) {
             // In aggressive cleanup mode a picture info should only exist if
             // it has some atlased layers
 #if !DISABLE_CACHING
             SkASSERT(!pictInfo->fPlotUsage.isEmpty());
 #endif
         } else {
-            // If there is no picture info for this picture then all of its
+            // If there is no picture info for this layer then all of its
             // layers should be non-atlased.
             SkASSERT(!layer->isAtlased());
         }
 
         if (layer->plot()) {
             SkASSERT(pictInfo);
             SkASSERT(pictInfo->fPictureID == layer->pictureID());
 
             SkASSERT(pictInfo->fPlotUsage.contains(layer->plot()));
 
             if (layer->locked()) {
-                SkASSERT(fPlotLocks[layer->plot()->id()] > 0);
+                plotLocks[layer->plot()->id()]++;
             }
         } 
     }
+
+    for (int i = 0; i < kNumPlotsX*kNumPlotsY; ++i) {
+        SkASSERT(plotLocks[i] == fPlotLocks[i]);
+    }
 }
 
 class GrAutoValidateCache : ::SkNoncopyable {
 public:
     explicit GrAutoValidateCache(GrLayerCache* cache)
         : fCache(cache) {
         fCache->validate();
     }
     ~GrAutoValidateCache() {
         fCache->validate();
@@ skipping 114 matching lines @@
 
 void GrLayerCache::processDeletedPictures() {
     SkTDArray<GrPictureDeletedMessage> deletedPictures;
     fPictDeletionInbox.poll(&deletedPictures);
 
     for (int i = 0; i < deletedPictures.count(); i++) {
         this->purge(deletedPictures[i].pictureID);
     }
 }