commit f1d666e1b48f8070ef1177fce156c08827f08eb8
author Mathieu Chartier <mathieuc@google.com> Thu Sep 03 16:13:34 2015 -0700
committer Mathieu Chartier <mathieuc@google.com> Thu Sep 03 17:33:19 2015 -0700
tree 772cbbe6652b32ea2be31532156295db27579390
parent 897ce64153e4758663e464fb5fb339f9a7b496c8

Add ScopedThreadSuspension

Fixes the TransitionFromRunnableToSuspended and
TransitionFromSuspendedToRunnable pattern that was prone to errors.

Change-Id: Ie6ae9c0357c83b4fc4899d05dfa0975553170267

compiler/driver/compiler_driver.cc

diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index ded70cd..9ee0a36 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -688,7 +688,7 @@
   const DexFile::CodeItem* code_item = dex_file->GetCodeItem(method->GetCodeItemOffset());
 
   // Go to native so that we don't block GC during compilation.
-  self->TransitionFromRunnableToSuspended(kNative);
+  ScopedThreadSuspension sts(self, kNative);
 
   std::vector<const DexFile*> dex_files;
   dex_files.push_back(dex_file);
@@ -718,7 +718,6 @@
                 dex_cache);
 
   self->GetJniEnv()->DeleteGlobalRef(jclass_loader);
-  self->TransitionFromSuspendedToRunnable();
 }
 
 CompiledMethod* CompilerDriver::CompileArtMethod(Thread* self, ArtMethod* method) {
@@ -737,7 +736,7 @@
       GetDexToDexCompilationLevel(self, *this, class_loader, *dex_file, class_def);
   const DexFile::CodeItem* code_item = dex_file->GetCodeItem(method->GetCodeItemOffset());
   // Go to native so that we don't block GC during compilation.
-  self->TransitionFromRunnableToSuspended(kNative);
+  ScopedThreadSuspension sts(self, kNative);
   CompileMethod(self,
                 this,
                 code_item,
@@ -751,7 +750,6 @@
                 true,
                 dex_cache);
   auto* compiled_method = GetCompiledMethod(MethodReference(dex_file, method_idx));
-  self->TransitionFromSuspendedToRunnable();
   return compiled_method;
 }
 
@@ -2382,7 +2380,7 @@
     }
 
     // Go to native so that we don't block GC during compilation.
-    soa.Self()->TransitionFromRunnableToSuspended(kNative);
+    ScopedThreadSuspension sts(soa.Self(), kNative);
 
     CompilerDriver* const driver = manager_->GetCompiler();
 
@@ -2437,8 +2435,6 @@
       it.Next();
     }
     DCHECK(!it.HasNext());
-
-    soa.Self()->TransitionFromSuspendedToRunnable();
   }
 
  private:

compiler/image_writer.cc

diff --git a/compiler/image_writer.cc b/compiler/image_writer.cc
index dbd3366..f318921 100644
--- a/compiler/image_writer.cc
+++ b/compiler/image_writer.cc
@@ -85,11 +85,9 @@
 bool ImageWriter::PrepareImageAddressSpace() {
   target_ptr_size_ = InstructionSetPointerSize(compiler_driver_.GetInstructionSet());
   {
-    Thread::Current()->TransitionFromSuspendedToRunnable();
+    ScopedObjectAccess soa(Thread::Current());
     PruneNonImageClasses();  // Remove junk
     ComputeLazyFieldsForImageClasses();  // Add useful information
-
-    Thread::Current()->TransitionFromRunnableToSuspended(kNative);
   }
   gc::Heap* heap = Runtime::Current()->GetHeap();
   heap->CollectGarbage(false);  // Remove garbage.
@@ -109,9 +107,10 @@
     CheckNonImageClassesRemoved();
   }
 
-  Thread::Current()->TransitionFromSuspendedToRunnable();
-  CalculateNewObjectOffsets();
-  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
+  {
+    ScopedObjectAccess soa(Thread::Current());
+    CalculateNewObjectOffsets();
+  }
 
   // This needs to happen after CalculateNewObjectOffsets since it relies on intern_table_bytes_ and
   // bin size sums being calculated.
@@ -164,14 +163,14 @@
   size_t oat_data_offset = 0;
   ElfWriter::GetOatElfInformation(oat_file.get(), &oat_loaded_size, &oat_data_offset);
 
-  Thread::Current()->TransitionFromSuspendedToRunnable();
-
-  CreateHeader(oat_loaded_size, oat_data_offset);
-  CopyAndFixupNativeData();
-  // TODO: heap validation can't handle these fix up passes.
-  Runtime::Current()->GetHeap()->DisableObjectValidation();
-  CopyAndFixupObjects();
-  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
+  {
+    ScopedObjectAccess soa(Thread::Current());
+    CreateHeader(oat_loaded_size, oat_data_offset);
+    CopyAndFixupNativeData();
+    // TODO: heap validation can't handle these fix up passes.
+    Runtime::Current()->GetHeap()->DisableObjectValidation();
+    CopyAndFixupObjects();
+  }
 
   SetOatChecksumFromElfFile(oat_file.get());