commit 25e0456b6ea13eba290b63ea88b6b7120ed89413
author Nicolas Geoffray <ngeoffray@google.com> Tue Mar 01 13:17:58 2016 +0000
committer Nicolas Geoffray <ngeoffray@google.com> Tue Mar 01 13:17:58 2016 +0000
tree 212c7433997a9e498ce68136ab511ae366e983e9
parent 47bce25b3eaf5c0e1d46f0555eaf4676f958a7a7

Give the JIT its own arena pool to avoid lock contentions.

Sharing it with the verifier and the class loader is not ideal,
especially at startup time.

bug:27398183
bug:23128949
Change-Id: I1b91663a13f6c5b33ad3b4be780d93eb7fe445b4

runtime/base/arena_allocator.cc

diff --git a/runtime/base/arena_allocator.cc b/runtime/base/arena_allocator.cc
index a4b38ea..44af3f7 100644
--- a/runtime/base/arena_allocator.cc
+++ b/runtime/base/arena_allocator.cc
@@ -183,10 +183,10 @@
   free(reinterpret_cast<void*>(memory_));
 }
 
-MemMapArena::MemMapArena(size_t size, bool low_4gb) {
+MemMapArena::MemMapArena(size_t size, bool low_4gb, const char* name) {
   std::string error_msg;
   map_.reset(MemMap::MapAnonymous(
-      "LinearAlloc", nullptr, size, PROT_READ | PROT_WRITE, low_4gb, false, &error_msg));
+      name, nullptr, size, PROT_READ | PROT_WRITE, low_4gb, false, &error_msg));
   CHECK(map_.get() != nullptr) << error_msg;
   memory_ = map_->Begin();
   size_ = map_->Size();
@@ -210,9 +210,12 @@
   }
 }
 
-ArenaPool::ArenaPool(bool use_malloc, bool low_4gb)
-    : use_malloc_(use_malloc), lock_("Arena pool lock", kArenaPoolLock), free_arenas_(nullptr),
-      low_4gb_(low_4gb) {
+ArenaPool::ArenaPool(bool use_malloc, bool low_4gb, const char* name)
+    : use_malloc_(use_malloc),
+      lock_("Arena pool lock", kArenaPoolLock),
+      free_arenas_(nullptr),
+      low_4gb_(low_4gb),
+      name_(name) {
   if (low_4gb) {
     CHECK(!use_malloc) << "low4gb must use map implementation";
   }
@@ -250,7 +253,7 @@
   }
   if (ret == nullptr) {
     ret = use_malloc_ ? static_cast<Arena*>(new MallocArena(size)) :
-        new MemMapArena(size, low_4gb_);
+        new MemMapArena(size, low_4gb_, name_);
   }
   ret->Reset();
   return ret;

runtime/base/arena_allocator.h

diff --git a/runtime/base/arena_allocator.h b/runtime/base/arena_allocator.h
index 8a96571..728f897 100644
--- a/runtime/base/arena_allocator.h
+++ b/runtime/base/arena_allocator.h
@@ -261,7 +261,7 @@
 
 class MemMapArena FINAL : public Arena {
  public:
-  MemMapArena(size_t size, bool low_4gb);
+  MemMapArena(size_t size, bool low_4gb, const char* name);
   virtual ~MemMapArena();
   void Release() OVERRIDE;
 
@@ -271,7 +271,9 @@
 
 class ArenaPool {
  public:
-  explicit ArenaPool(bool use_malloc = true, bool low_4gb = false);
+  ArenaPool(bool use_malloc = true,
+            bool low_4gb = false,
+            const char* name = "LinearAlloc");
   ~ArenaPool();
   Arena* AllocArena(size_t size) REQUIRES(!lock_);
   void FreeArenaChain(Arena* first) REQUIRES(!lock_);
@@ -287,6 +289,7 @@
   mutable Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
   Arena* free_arenas_ GUARDED_BY(lock_);
   const bool low_4gb_;
+  const char* name_;
   DISALLOW_COPY_AND_ASSIGN(ArenaPool);
 };