Revert of Refactor GrBufferAllocPools to use resource cache (patchset #15 id:280001 of https://codereview.chromium.org/1139753002/)

Reason for revert:
Will reland after Chromium branch

Original issue's description:
> Refactor GrBufferAllocPools to use resource cache
>
> Committed: https://skia.googlesource.com/skia/+/e935f1a0e2351373c33600b8388492ce1218014a

TBR=bsalomon@google.com,joshualitt@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1204773003

1 files changed, 26 insertions, 6 deletions

diff --git a/src/gpu/GrBufferAllocPool.h b/src/gpu/GrBufferAllocPool.h
index bbcb8a5d7c..cd5d1971da 100644
--- a/src/gpu/GrBufferAllocPool.h
+++ b/src/gpu/GrBufferAllocPool.h
@@ -64,12 +64,16 @@ protected:
      * @param bufferSize            The minimum size of created buffers.
      *                              This value will be clamped to some
      *                              reasonable minimum.
+     * @param preallocBufferCnt     The pool will allocate this number of
+     *                              buffers at bufferSize and keep them until it
+     *                              is destroyed.
      */
      GrBufferAllocPool(GrGpu* gpu,
                        BufferType bufferType,
-                       size_t   bufferSize = 0);
+                       size_t   bufferSize = 0,
+                       int preallocBufferCnt = 0);
 
-     virtual ~GrBufferAllocPool();
+    virtual ~GrBufferAllocPool();
 
     /**
      * Returns a block of memory to hold data. A buffer designated to hold the
@@ -95,7 +99,7 @@ protected:
                     const GrGeometryBuffer** buffer,
                     size_t* offset);
 
-    GrGeometryBuffer* getBuffer(size_t size);
+    GrGeometryBuffer* createBuffer(size_t size);
 
 private:
     struct BufferBlock {
@@ -105,7 +109,6 @@ private:
 
     bool createBlock(size_t requestSize);
     void destroyBlock();
-    void deleteBlocks();
     void flushCpuData(const BufferBlock& block, size_t flushSize);
 #ifdef SK_DEBUG
     void validate(bool unusedBlockAllowed = false) const;
@@ -114,10 +117,15 @@ private:
     size_t                          fBytesInUse;
 
     GrGpu*                          fGpu;
+    SkTDArray<GrGeometryBuffer*>    fPreallocBuffers;
     size_t                          fMinBlockSize;
     BufferType                      fBufferType;
 
     SkTArray<BufferBlock>           fBlocks;
+    int                             fPreallocBuffersInUse;
+    // We attempt to cycle through the preallocated buffers rather than
+    // always starting from the first.
+    int                             fPreallocBufferStartIdx;
     SkAutoMalloc                    fCpuData;
     void*                           fBufferPtr;
     size_t                          fGeometryBufferMapThreshold;
@@ -134,8 +142,13 @@ public:
      * Constructor
      *
      * @param gpu                   The GrGpu used to create the vertex buffers.
+     * @param bufferSize            The minimum size of created VBs. This value
+     *                              will be clamped to some reasonable minimum.
+     * @param preallocBufferCnt     The pool will allocate this number of VBs at
+     *                              bufferSize and keep them until it is
+     *                              destroyed.
      */
-    GrVertexBufferAllocPool(GrGpu* gpu);
+    GrVertexBufferAllocPool(GrGpu* gpu, size_t bufferSize = 0, int preallocBufferCnt = 0);
 
     /**
      * Returns a block of memory to hold vertices. A buffer designated to hold
@@ -178,8 +191,15 @@ public:
      * Constructor
      *
      * @param gpu                   The GrGpu used to create the index buffers.
+     * @param bufferSize            The minimum size of created IBs. This value
+     *                              will be clamped to some reasonable minimum.
+     * @param preallocBufferCnt     The pool will allocate this number of VBs at
+     *                              bufferSize and keep them until it is
+     *                              destroyed.
      */
-    GrIndexBufferAllocPool(GrGpu* gpu);
+    GrIndexBufferAllocPool(GrGpu* gpu,
+                           size_t bufferSize = 0,
+                           int preallocBufferCnt = 0);
 
     /**
      * Returns a block of memory to hold indices. A buffer designated to hold