Change Atlas recycling to track current flush count and recycle if Atlas not used in current flush.

src/gpu/GrTextStrike.cpp

Index: src/gpu/GrTextStrike.cpp
diff --git a/src/gpu/GrTextStrike.cpp b/src/gpu/GrTextStrike.cpp
index 9373351f227ee0c0076af7016d64f3a772a5f9a3..570b0a9ac6aa7b72ea07fd62867d0cb93c1b266e 100644
--- a/src/gpu/GrTextStrike.cpp
+++ b/src/gpu/GrTextStrike.cpp
@@ -86,9 +86,6 @@ void GrFontCache::purgeExceptFor(GrTextStrike* preserveStrike) {
             fCache.removeAt(index, strikeToPurge->fFontScalerKey->getHash());
             this->detachStrikeFromList(strikeToPurge);
             delete strikeToPurge;
-        } else {
-            // for the remaining strikes, we just mark them unused
-            GrAtlas::MarkAllUnused(strikeToPurge->fAtlas);
         }
     }
 #if FONT_CACHE_STATS
@@ -96,7 +93,7 @@ void GrFontCache::purgeExceptFor(GrTextStrike* preserveStrike) {
 #endif
 }
 
-void GrFontCache::freeAtlasExceptFor(GrTextStrike* preserveStrike) {
+void GrFontCache::freeAtlasExceptFor(GrTextStrike* preserveStrike, uint64_t currentFlushCount) {
     GrTextStrike* strike = fTail;
     while (strike) {
         if (strike == preserveStrike) {
@@ -105,7 +102,7 @@ void GrFontCache::freeAtlasExceptFor(GrTextStrike* preserveStrike) {
         }
         GrTextStrike* strikeToPurge = strike;
         strike = strikeToPurge->fPrev;
-        if (strikeToPurge->removeUnusedAtlases()) {
+        if (strikeToPurge->removeUnusedAtlases(currentFlushCount)) {
             if (NULL == strikeToPurge->fAtlas) {
                 int index = fCache.slowFindIndex(strikeToPurge);
                 GrAssert(index >= 0);
@@ -184,8 +181,10 @@ GrTextStrike::GrTextStrike(GrFontCache* cache, const GrKey* key,
 // SkTDArray::visitAll() (see destructor & removeUnusedAtlases())
 static void free_glyph(GrGlyph*& glyph) { glyph->free(); }
 
+static uint64_t gCurrentFlushCount = 0;

[bsalomon, 2013/08/13 21:18:28]

wha? There can be multiple GrContexts

[jvanverth1, 2013/08/14 13:24:32]

A bit of a hack to get around the fact that visitAll() only takes one argument.
But I agree it's not thread-safe (and a hack). Changed to something cleaner,
below.

+
 static void invalidate_glyph(GrGlyph*& glyph) {
-    if (glyph->fAtlas && !glyph->fAtlas->used()) {
+    if (glyph->fAtlas && glyph->fAtlas->lastFlush() < gCurrentFlushCount) {
         glyph->fAtlas = NULL;
     }
 }
@@ -214,14 +213,15 @@ GrGlyph* GrTextStrike::generateGlyph(GrGlyph::PackedID packed,
     return glyph;
 }
 
-bool GrTextStrike::removeUnusedAtlases() {
+bool GrTextStrike::removeUnusedAtlases(uint64_t currentFlushCount) {
+    gCurrentFlushCount = currentFlushCount;
     fCache.getArray().visitAll(invalidate_glyph);
-    return GrAtlas::RemoveUnusedAtlases(fAtlasMgr, &fAtlas);
+    return GrAtlas::RemoveUnusedAtlases(fAtlasMgr, &fAtlas, currentFlushCount);
 
     return false;
 }
 
-bool GrTextStrike::getGlyphAtlas(GrGlyph* glyph, GrFontScaler* scaler) {
+bool GrTextStrike::getGlyphAtlas(GrGlyph* glyph, GrFontScaler* scaler, uint64_t currentFlushCount) {
 #if 0   // testing hack to force us to flush our cache often
     static int gCounter;
     if ((++gCounter % 10) == 0) return false;
@@ -231,7 +231,7 @@ bool GrTextStrike::getGlyphAtlas(GrGlyph* glyph, GrFontScaler* scaler) {
     GrAssert(scaler);
     GrAssert(fCache.contains(glyph));
     if (glyph->fAtlas) {
-        glyph->fAtlas->setUsed(true);
+        glyph->fAtlas->setLastFlush(currentFlushCount);
         return true;
     }
 
@@ -256,6 +256,6 @@ bool GrTextStrike::getGlyphAtlas(GrGlyph* glyph, GrFontScaler* scaler) {
     }
 
     glyph->fAtlas = atlas;
-    atlas->setUsed(true);
+    atlas->setLastFlush(currentFlushCount);
     return true;
 }