Ensure we flush TextBlobCache message queue.

If we create and delete TextBlobs without actually renderering them,
their deletion messages can back up in the message queue. This adds
a routine to GrContext to ensure these messages get flushed.

Bug: 703297
Change-Id: Icc222373ac2a954dc3b77190cad79070ea562ba2
Reviewed-on: https://skia-review.googlesource.com/82686
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

1 files changed, 55 insertions, 0 deletions

diff --git a/src/gpu/text/GrTextBlobCache.cpp b/src/gpu/text/GrTextBlobCache.cpp
index f1162e2634..f90ed9937c 100644
--- a/src/gpu/text/GrTextBlobCache.cpp
+++ b/src/gpu/text/GrTextBlobCache.cpp
@@ -31,3 +31,58 @@ void GrTextBlobCache::PostPurgeBlobMessage(uint32_t id) {
     SkASSERT(id != SK_InvalidGenID);
     SkMessageBus<PurgeBlobMessage>::Post(PurgeBlobMessage({id}));
 }
+
+void GrTextBlobCache::purgeStaleBlobs() {
+    SkTArray<PurgeBlobMessage> msgs;
+    fPurgeBlobInbox.poll(&msgs);
+
+    for (const auto& msg : msgs) {
+        auto* idEntry = fBlobIDCache.find(msg.fID);
+        if (!idEntry) {
+            // no cache entries for id
+            continue;
+        }
+
+        // remove all blob entries from the LRU list
+        for (const auto& blob : idEntry->fBlobs) {
+            fBlobList.remove(blob.get());
+        }
+
+        // drop the idEntry itself (unrefs all blobs)
+        fBlobIDCache.remove(msg.fID);
+    }
+}
+
+void GrTextBlobCache::checkPurge(GrAtlasTextBlob* blob) {
+    // First, purge all stale blob IDs.
+    this->purgeStaleBlobs();
+
+    // If we are still over budget, then unref until we are below budget again
+    if (fPool.size() > fBudget) {
+        BitmapBlobList::Iter iter;
+        iter.init(fBlobList, BitmapBlobList::Iter::kTail_IterStart);
+        GrAtlasTextBlob* lruBlob = nullptr;
+        while (fPool.size() > fBudget && (lruBlob = iter.get()) && lruBlob != blob) {
+            // Backup the iterator before removing and unrefing the blob
+            iter.prev();
+
+            this->remove(lruBlob);
+        }
+
+        // If we break out of the loop with lruBlob == blob, then we haven't purged enough
+        // use the call back and try to free some more.  If we are still overbudget after this,
+        // then this single textblob is over our budget
+        if (blob && lruBlob == blob) {
+            (*fCallback)(fData);
+        }
+
+#ifdef SPEW_BUDGET_MESSAGE
+        if (fPool.size() > fBudget) {
+            SkDebugf("Single textblob is larger than our whole budget");
+        }
+#endif
+    }
+}
+
+
+