commit 340dafabc8e88378e395cda9027cf17726910e91
author Nicolas Geoffray <ngeoffray@google.com> Fri Nov 18 16:03:10 2016 +0000
committer Nicolas Geoffray <ngeoffray@google.com> Tue Nov 22 13:08:29 2016 +0000
tree f742cfc9b9eb3fdf0245a66491d39fb841da7c01
parent 71d15102b52af67e8fe1193192aa2b4cd1956ae0

Use a per-thread VerifierDeps.

Avoid lock contention on a singleton VerifierDeps by allocating
temporary per-thread VerifierDeps that get merged after verification.

This saves around ~35% compile-times on interpret-only.

Only the creation of extra strings is guarded by a lock, for simplicity.

Test: test-art-host, test-art-target
bug: 32641252
bug: 30937355

Change-Id: I11a2367da882b58e39afa7b42cba2e74a209b75d

runtime/base/mutex.cc

diff --git a/runtime/base/mutex.cc b/runtime/base/mutex.cc
index 5d92298..0970abd 100644
--- a/runtime/base/mutex.cc
+++ b/runtime/base/mutex.cc
@@ -48,7 +48,7 @@
 Mutex* Locks::modify_ldt_lock_ = nullptr;
 MutatorMutex* Locks::mutator_lock_ = nullptr;
 Mutex* Locks::profiler_lock_ = nullptr;
-Mutex* Locks::verifier_deps_lock_ = nullptr;
+ReaderWriterMutex* Locks::verifier_deps_lock_ = nullptr;
 ReaderWriterMutex* Locks::oat_file_manager_lock_ = nullptr;
 Mutex* Locks::host_dlopen_handles_lock_ = nullptr;
 Mutex* Locks::reference_processor_lock_ = nullptr;
@@ -1039,7 +1039,7 @@
 
     UPDATE_CURRENT_LOCK_LEVEL(kVerifierDepsLock);
     DCHECK(verifier_deps_lock_ == nullptr);
-    verifier_deps_lock_ = new Mutex("verifier deps lock", current_lock_level);
+    verifier_deps_lock_ = new ReaderWriterMutex("verifier deps lock", current_lock_level);
 
     UPDATE_CURRENT_LOCK_LEVEL(kHostDlOpenHandlesLock);
     DCHECK(host_dlopen_handles_lock_ == nullptr);

runtime/base/mutex.h

diff --git a/runtime/base/mutex.h b/runtime/base/mutex.h
index 74b786c..7e73e0d 100644
--- a/runtime/base/mutex.h
+++ b/runtime/base/mutex.h
@@ -658,8 +658,8 @@
   // Guards opened oat files in OatFileManager.
   static ReaderWriterMutex* oat_file_manager_lock_ ACQUIRED_AFTER(modify_ldt_lock_);
 
-  // Guards verifier dependency collection in VerifierDeps.
-  static Mutex* verifier_deps_lock_ ACQUIRED_AFTER(oat_file_manager_lock_);
+  // Guards extra string entries for VerifierDeps.
+  static ReaderWriterMutex* verifier_deps_lock_ ACQUIRED_AFTER(oat_file_manager_lock_);
 
   // Guards dlopen_handles_ in DlOpenOatFile.
   static Mutex* host_dlopen_handles_lock_ ACQUIRED_AFTER(verifier_deps_lock_);

runtime/base/stl_util.h

diff --git a/runtime/base/stl_util.h b/runtime/base/stl_util.h
index a53dcea..d5f375a 100644
--- a/runtime/base/stl_util.h
+++ b/runtime/base/stl_util.h
@@ -18,6 +18,7 @@
 #define ART_RUNTIME_BASE_STL_UTIL_H_
 
 #include <algorithm>
+#include <set>
 #include <sstream>
 
 #include "base/logging.h"
@@ -187,6 +188,12 @@
   using type = T;
 };
 
+// Merge `other` entries into `to_update`.
+template <typename T>
+static inline void MergeSets(std::set<T>& to_update, const std::set<T>& other) {
+  to_update.insert(other.begin(), other.end());
+}
+
 }  // namespace art
 
 #endif  // ART_RUNTIME_BASE_STL_UTIL_H_