From 016ae448e08813d444cf91d4c8383931f54edd09 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Niels=20M=C3=B6ller?= Date: Thu, 7 Apr 2022 16:19:15 +0200 Subject: [PATCH] Reland "Delete unused class GlobalMutex" This is a reland of commit 5831afb8328cbecdbdbee882280ef907a09d9f31 Original change's description: > Delete unused class GlobalMutex > > Bug: webrtc:13869 > Change-Id: Id3655bdd24630b78e83b606291605a37129fd4bc > Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/258131 > Reviewed-by: Mirko Bonadei > Commit-Queue: Niels Moller > Cr-Commit-Position: refs/heads/main@{#36478} Bug: webrtc:13869 Change-Id: I43f41c9128fc8054fc0051cbeb4dbe5cfc91f458 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/258137 Reviewed-by: Mirko Bonadei Commit-Queue: Niels Moller Cr-Commit-Position: refs/heads/main@{#36491} --- rtc_base/synchronization/BUILD.gn | 3 +- rtc_base/synchronization/mutex.cc | 39 ---------------------- rtc_base/synchronization/mutex.h | 35 ------------------- rtc_base/synchronization/mutex_unittest.cc | 25 -------------- 4 files changed, 1 insertion(+), 101 deletions(-) delete mode 100644 rtc_base/synchronization/mutex.cc diff --git a/rtc_base/synchronization/BUILD.gn b/rtc_base/synchronization/BUILD.gn index 9d891f3d8e..406f5b57ee 100644 --- a/rtc_base/synchronization/BUILD.gn +++ b/rtc_base/synchronization/BUILD.gn @@ -21,9 +21,8 @@ rtc_library("yield") { deps = [] } -rtc_library("mutex") { +rtc_source_set("mutex") { sources = [ - "mutex.cc", "mutex.h", "mutex_critical_section.h", "mutex_pthread.h", diff --git a/rtc_base/synchronization/mutex.cc b/rtc_base/synchronization/mutex.cc deleted file mode 100644 index 6c2d6ff7f0..0000000000 --- a/rtc_base/synchronization/mutex.cc +++ /dev/null @@ -1,39 +0,0 @@ -/* - * Copyright 2020 The WebRTC Project Authors. All rights reserved. - * - * Use of this source code is governed by a BSD-style license - * that can be found in the LICENSE file in the root of the source - * tree. An additional intellectual property rights grant can be found - * in the file PATENTS. All contributing project authors may - * be found in the AUTHORS file in the root of the source tree. - */ - -#include "rtc_base/synchronization/mutex.h" - -#include "rtc_base/checks.h" -#include "rtc_base/synchronization/yield.h" - -namespace webrtc { - -#if !defined(WEBRTC_ABSL_MUTEX) -void GlobalMutex::Lock() { - while (mutex_locked_.exchange(1)) { - YieldCurrentThread(); - } -} - -void GlobalMutex::Unlock() { - int old = mutex_locked_.exchange(0); - RTC_DCHECK_EQ(old, 1) << "Unlock called without calling Lock first"; -} - -GlobalMutexLock::GlobalMutexLock(GlobalMutex* mutex) : mutex_(mutex) { - mutex_->Lock(); -} - -GlobalMutexLock::~GlobalMutexLock() { - mutex_->Unlock(); -} -#endif // #if !defined(WEBRTC_ABSL_MUTEX) - -} // namespace webrtc diff --git a/rtc_base/synchronization/mutex.h b/rtc_base/synchronization/mutex.h index c6af9e9838..2cf0e67c3d 100644 --- a/rtc_base/synchronization/mutex.h +++ b/rtc_base/synchronization/mutex.h @@ -72,41 +72,6 @@ class RTC_SCOPED_LOCKABLE MutexLock final { Mutex* mutex_; }; -// A mutex used to protect global variables. Do NOT use for other purposes. -#if defined(WEBRTC_ABSL_MUTEX) -using GlobalMutex = absl::Mutex; -using GlobalMutexLock = absl::MutexLock; -#else -class RTC_LOCKABLE GlobalMutex final { - public: - GlobalMutex(const GlobalMutex&) = delete; - GlobalMutex& operator=(const GlobalMutex&) = delete; - - constexpr explicit GlobalMutex(absl::ConstInitType /*unused*/) - : mutex_locked_(0) {} - - void Lock() RTC_EXCLUSIVE_LOCK_FUNCTION(); - void Unlock() RTC_UNLOCK_FUNCTION(); - - private: - std::atomic mutex_locked_; // 0 means lock not taken, 1 means taken. -}; - -// GlobalMutexLock, for serializing execution through a scope. -class RTC_SCOPED_LOCKABLE GlobalMutexLock final { - public: - GlobalMutexLock(const GlobalMutexLock&) = delete; - GlobalMutexLock& operator=(const GlobalMutexLock&) = delete; - - explicit GlobalMutexLock(GlobalMutex* mutex) - RTC_EXCLUSIVE_LOCK_FUNCTION(mutex_); - ~GlobalMutexLock() RTC_UNLOCK_FUNCTION(); - - private: - GlobalMutex* mutex_; -}; -#endif // if defined(WEBRTC_ABSL_MUTEX) - } // namespace webrtc #endif // RTC_BASE_SYNCHRONIZATION_MUTEX_H_ diff --git a/rtc_base/synchronization/mutex_unittest.cc b/rtc_base/synchronization/mutex_unittest.cc index a07e8fa429..fcca78d18b 100644 --- a/rtc_base/synchronization/mutex_unittest.cc +++ b/rtc_base/synchronization/mutex_unittest.cc @@ -177,30 +177,5 @@ TEST(MutexTest, ProtectsSharedResourceWithMutexAndMutexLocker) { EXPECT_EQ(0, runner.shared_value()); } -TEST(MutexTest, ProtectsSharedResourceWithGlobalMutexAndRawMutexLocker) { - std::vector> threads; - LockRunner> runner(absl::kConstInit); - StartThreads(threads, &runner); - runner.SetExpectedThreadCount(kNumThreads); - EXPECT_TRUE(runner.Run()); - EXPECT_EQ(0, runner.shared_value()); -} - -TEST(MutexTest, ProtectsSharedResourceWithGlobalMutexAndMutexLocker) { - std::vector> threads; - LockRunner> runner( - absl::kConstInit); - StartThreads(threads, &runner); - runner.SetExpectedThreadCount(kNumThreads); - EXPECT_TRUE(runner.Run()); - EXPECT_EQ(0, runner.shared_value()); -} - -TEST(MutexTest, GlobalMutexCanHaveStaticStorageDuration) { - ABSL_CONST_INIT static GlobalMutex global_lock(absl::kConstInit); - global_lock.Lock(); - global_lock.Unlock(); -} - } // namespace } // namespace webrtc