Add method to GrContext to purge unlocked resources.

Beyond setting the total cache limits this method enables clients to
request to purge a specific number of bytes, as well as specify their
preference to purge scratch resources over resources of other types.

Change-Id: I9259d5544d34251575d77eebe599388f213ff3ce
Reviewed-on: https://skia-review.googlesource.com/17987
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Derek Sollenberger <djsollen@google.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/gpu/GrContext.h b/include/gpu/GrContext.h
index 5bd9574678..0f3d925113 100644
--- a/include/gpu/GrContext.h
+++ b/include/gpu/GrContext.h
@@ -172,6 +172,18 @@ public:
      */
     void purgeResourcesNotUsedInMs(std::chrono::milliseconds ms);
 
+    /**
+     * Purge unlocked resources from the cache until the the provided byte count has been reached
+     * or we have purged all unlocked resources. The default policy is to purge in LRU order, but
+     * can be overridden to prefer purging scratch resources (in LRU order) prior to purging other
+     * resource types.
+     *
+     * @param maxBytesToPurge the desired number of bytes to be purged.
+     * @param preferScratchResources If true scratch resources will be purged prior to other
+     *                               resource types.
+     */
+    void purgeUnlockedResources(size_t bytesToPurge, bool preferScratchResources);
+
     /** Access the context capabilities */
     const GrCaps* caps() const { return fCaps; }