commit b8a0b94735f188bc739e4c55479c37699006b881
author Ian Rogers <irogers@google.com> Tue Aug 20 18:09:52 2013 -0700
committer Ian Rogers <irogers@google.com> Tue Aug 20 18:11:09 2013 -0700
tree 6620437e5019924f9da7b1c9a6408cf4a113b3e5
parent aa836f7fa2ef359cf8ec1ef98d924f7971ba8352

Switch JNI globals lock to reader-writer.

Also, verifier rejected classes lock. These locks show as contended during
dex2oat, however, they're commonly only read access is required.

Change-Id: If8bb834cc69cd8c26494c87fb7f7b20d4e41cdfd

runtime/verifier/method_verifier.cc

diff --git a/runtime/verifier/method_verifier.cc b/runtime/verifier/method_verifier.cc
index 4d2f36f..34a0f73 100644
--- a/runtime/verifier/method_verifier.cc
+++ b/runtime/verifier/method_verifier.cc
@@ -4202,7 +4202,7 @@
 ReaderWriterMutex* MethodVerifier::devirt_maps_lock_ = NULL;
 MethodVerifier::DevirtualizationMapTable* MethodVerifier::devirt_maps_ = NULL;
 
-Mutex* MethodVerifier::rejected_classes_lock_ = NULL;
+ReaderWriterMutex* MethodVerifier::rejected_classes_lock_ = NULL;
 MethodVerifier::RejectedClassesTable* MethodVerifier::rejected_classes_ = NULL;
 
 void MethodVerifier::Init() {
@@ -4227,9 +4227,9 @@
       devirt_maps_ = new MethodVerifier::DevirtualizationMapTable();
     }
 
-    rejected_classes_lock_ = new Mutex("verifier rejected classes lock");
+    rejected_classes_lock_ = new ReaderWriterMutex("verifier rejected classes lock");
     {
-      MutexLock mu(self, *rejected_classes_lock_);
+      WriterMutexLock mu(self, *rejected_classes_lock_);
       rejected_classes_ = new MethodVerifier::RejectedClassesTable;
     }
   }
@@ -4267,7 +4267,7 @@
     devirt_maps_lock_ = NULL;
 
     {
-      MutexLock mu(self, *rejected_classes_lock_);
+      WriterMutexLock mu(self, *rejected_classes_lock_);
       delete rejected_classes_;
       rejected_classes_ = NULL;
     }
@@ -4280,7 +4280,7 @@
 void MethodVerifier::AddRejectedClass(ClassReference ref) {
   DCHECK(Runtime::Current()->IsCompiler());
   {
-    MutexLock mu(Thread::Current(), *rejected_classes_lock_);
+    WriterMutexLock mu(Thread::Current(), *rejected_classes_lock_);
     rejected_classes_->insert(ref);
   }
   CHECK(IsClassRejected(ref));
@@ -4288,7 +4288,7 @@
 
 bool MethodVerifier::IsClassRejected(ClassReference ref) {
   DCHECK(Runtime::Current()->IsCompiler());
-  MutexLock mu(Thread::Current(), *rejected_classes_lock_);
+  ReaderMutexLock mu(Thread::Current(), *rejected_classes_lock_);
   return (rejected_classes_->find(ref) != rejected_classes_->end());
 }