Shared Raster Worker Threads

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
old mode 100644
new mode 100755
index 93e41b706e71251c34aa2e60ccdcffe7ffa8699a..1941985b7d6f179f32b4baff39ff6cdf7a70cb04
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -22,10 +22,13 @@
 #include "base/path_service.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_tokenizer.h"
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_local.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/values.h"
+#include "cc/base/switches.h"
+#include "cc/resources/raster_worker_pool.h"
 #include "content/child/appcache/appcache_dispatcher.h"
 #include "content/child/appcache/appcache_frontend_impl.h"
 #include "content/child/child_histogram_message_filter.h"
@@ -157,6 +160,9 @@ const int64 kInitialIdleHandlerDelayMs = 1000;
 const int64 kShortIdleHandlerDelayMs = 1000;
 const int64 kLongIdleHandlerDelayMs = 30*1000;
 const int kIdleCPUUsageThresholdInPercents = 3;
+const int kMinRasterThreads = 1;
+const int kMaxRasterThreads = 64;
+const int kDefaultNumRasterThreads = 1;
 
 // Keep the global RenderThreadImpl in a TLS slot so it is impossible to access
 // incorrectly from the wrong thread.
@@ -407,6 +413,20 @@ void RenderThreadImpl::Init() {
   // it doesn't have to be the same thread RenderThreadImpl is created on.
   allocate_gpu_memory_buffer_thread_checker_.DetachFromThread();
 
+  int num_raster_threads = kDefaultNumRasterThreads;
+  if (command_line.HasSwitch(cc::switches::kNumRasterThreads)) {
+    int num_threads;
+    std::string string_value =
+        command_line.GetSwitchValueASCII(cc::switches::kNumRasterThreads);
+    if (base::StringToInt(string_value, &num_threads) &&
+        num_threads >= kMinRasterThreads && num_threads <= kMaxRasterThreads)
+      num_raster_threads = num_threads;
+    else
+      LOG(WARNING) << "Failed to parse switch " <<
+                      cc::switches::kNumRasterThreads  << ": " << string_value;

[reveman, 2014/01/07 17:24:06]

nit: multiple line "else". please use "{" "}" for both "if" and "else" clause

[sohanjg, 2014/01/08 05:55:43]

Done.

+  }
+  cc::RasterWorkerPool::SetNumRasterThreads(num_raster_threads);
+
   TRACE_EVENT_END_ETW("RenderThreadImpl::Init", 0, "");
 }