Add --resetGpuContext to both DM and nanobench.

bench/nanobench.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 <ctype.h>
 
 #include "Benchmark.h"
@@ skipping 31 matching lines @@
 DEFINE_bool2(verbose, v, false, "Print all samples.");
 DEFINE_string(config, "nonrendering 8888 gpu", "Configs to measure. Options: "
               "565 8888 gpu nonrendering debug nullgpu msaa4 msaa16 nvprmsaa4 nvprmsaa16 angle");
 DEFINE_double(gpuMs, 5, "Target bench time in millseconds for GPU.");
 DEFINE_int32(gpuFrameLag, 5, "Overestimate of maximum number of frames GPU allows to lag.");
 
 DEFINE_bool(cpu, true, "Master switch for CPU-bound work.");
 DEFINE_bool(gpu, true, "Master switch for GPU-bound work.");
 
 DEFINE_string(outResultsFile, "", "If given, write results here as JSON.");
+DEFINE_bool(resetGpuContext, true, "Reset the GrContext before running each bench.");
 
 
 static SkString humanize(double ms) {
     if (ms > 1e+3) return SkStringPrintf("%.3gs",  ms/1e3);
     if (ms < 1e-3) return SkStringPrintf("%.3gns", ms*1e6);
     if (ms < 1)    return SkStringPrintf("%.3gµs", ms*1e3);
     return SkStringPrintf("%.3gms", ms);
 }
 
 static double time(int loops, Benchmark* bench, SkCanvas* canvas, SkGLContextHelper* gl) {
@@ skipping 145 matching lines @@
             t->surface.reset(code);                                        \
             targets->push(t);                                              \
         }
     if (FLAGS_cpu) {
         CPU_TARGET(nonrendering, kNonRendering_Backend, NULL)
         CPU_TARGET(8888, kRaster_Backend, SkSurface::NewRaster(_8888))
         CPU_TARGET(565,  kRaster_Backend, SkSurface::NewRaster(_565))
     }
 
 #if SK_SUPPORT_GPU
+    if (FLAGS_resetGpuContext) {
+        gGrFactory.destroyContexts();
+    }
+
     #define GPU_TARGET(config, ctxType, info, samples)                                            \
         if (Target* t = is_enabled(bench, Benchmark::kGPU_Backend, #config)) {                    \
             t->surface.reset(SkSurface::NewRenderTarget(gGrFactory.get(ctxType), info, samples)); \
             t->gl = gGrFactory.getGLContext(ctxType);                                             \
             targets->push(t);                                                                     \
         }
     if (FLAGS_gpu) {
         GPU_TARGET(gpu,      GrContextFactory::kNative_GLContextType, _8888, 0)
         GPU_TARGET(msaa4,    GrContextFactory::kNative_GLContextType, _8888, 4)
         GPU_TARGET(msaa16,   GrContextFactory::kNative_GLContextType, _8888, 16)
@@ skipping 127 matching lines @@
     }
 
     return 0;
 }
 
 #if !defined SK_BUILD_FOR_IOS
 int main(int argc, char * const argv[]) {
     return tool_main(argc, (char**) argv);
 }
 #endif