Clarify expectation on GlobalLock
Merge GlobalLock and GlobalLockPod, make member private.
annotate creation of all GlobalLocks with ABSL_CONST_INIT
Bug: None
Change-Id: I29abcc86796ec0e45b15df7d26392309d1bf7324
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/156303
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29447}
diff --git a/media/BUILD.gn b/media/BUILD.gn
index b451fef..726a66d 100644
--- a/media/BUILD.gn
+++ b/media/BUILD.gn
@@ -386,6 +386,7 @@
"../rtc_base/third_party/sigslot",
"../system_wrappers",
"//third_party/abseil-cpp/absl/algorithm:container",
+ "//third_party/abseil-cpp/absl/base:core_headers",
"//third_party/abseil-cpp/absl/types:optional",
]
diff --git a/media/sctp/sctp_transport.cc b/media/sctp/sctp_transport.cc
index 5b631ff..2c449e7 100644
--- a/media/sctp/sctp_transport.cc
+++ b/media/sctp/sctp_transport.cc
@@ -24,6 +24,7 @@
#include <memory>
#include "absl/algorithm/container.h"
+#include "absl/base/attributes.h"
#include "absl/types/optional.h"
#include "media/base/codec.h"
#include "media/base/media_channel.h"
@@ -49,8 +50,8 @@
static constexpr size_t kSctpMtu = 1200;
// Set the initial value of the static SCTP Data Engines reference count.
-int g_usrsctp_usage_count = 0;
-rtc::GlobalLockPod g_usrsctp_lock_;
+ABSL_CONST_INIT int g_usrsctp_usage_count = 0;
+ABSL_CONST_INIT rtc::GlobalLock g_usrsctp_lock_;
// DataMessageType is used for the SCTP "Payload Protocol Identifier", as
// defined in http://tools.ietf.org/html/rfc4960#section-14.4
diff --git a/pc/BUILD.gn b/pc/BUILD.gn
index 18025b8..1b63f1d 100644
--- a/pc/BUILD.gn
+++ b/pc/BUILD.gn
@@ -124,6 +124,7 @@
"../system_wrappers:field_trial",
"../system_wrappers:metrics",
"//third_party/abseil-cpp/absl/algorithm:container",
+ "//third_party/abseil-cpp/absl/base:core_headers",
"//third_party/abseil-cpp/absl/memory",
"//third_party/abseil-cpp/absl/strings",
"//third_party/abseil-cpp/absl/types:optional",
diff --git a/pc/srtp_session.cc b/pc/srtp_session.cc
index 9d67669..4108c12 100644
--- a/pc/srtp_session.cc
+++ b/pc/srtp_session.cc
@@ -10,6 +10,7 @@
#include "pc/srtp_session.h"
+#include "absl/base/attributes.h"
#include "media/base/rtp_utils.h"
#include "pc/external_hmac.h"
#include "rtc_base/critical_section.h"
@@ -362,8 +363,8 @@
return DoSetKey(type, cs, key, len, extension_ids);
}
-int g_libsrtp_usage_count = 0;
-rtc::GlobalLockPod g_libsrtp_lock;
+ABSL_CONST_INIT int g_libsrtp_usage_count = 0;
+ABSL_CONST_INIT rtc::GlobalLock g_libsrtp_lock;
// static
bool SrtpSession::IncrementLibsrtpUsageCountAndMaybeInit() {
diff --git a/pc/srtp_session.h b/pc/srtp_session.h
index 8bfd6d1..5aa7158 100644
--- a/pc/srtp_session.h
+++ b/pc/srtp_session.h
@@ -118,7 +118,7 @@
int rtp_auth_tag_len_ = 0;
int rtcp_auth_tag_len_ = 0;
bool inited_ = false;
- static rtc::GlobalLockPod lock_;
+ static rtc::GlobalLock lock_;
int last_send_seq_num_ = -1;
bool external_auth_active_ = false;
bool external_auth_enabled_ = false;
diff --git a/rtc_base/BUILD.gn b/rtc_base/BUILD.gn
index 8f13b0a..0fee5e0 100644
--- a/rtc_base/BUILD.gn
+++ b/rtc_base/BUILD.gn
@@ -1197,6 +1197,7 @@
"memory:unittests",
"third_party/base64",
"third_party/sigslot",
+ "//third_party/abseil-cpp/absl/base:core_headers",
"//third_party/abseil-cpp/absl/memory",
]
}
diff --git a/rtc_base/critical_section.cc b/rtc_base/critical_section.cc
index 9e3615e..1969ede 100644
--- a/rtc_base/critical_section.cc
+++ b/rtc_base/critical_section.cc
@@ -216,13 +216,13 @@
cs_->Leave();
}
-void GlobalLockPod::Lock() {
+void GlobalLock::Lock() {
#if !defined(WEBRTC_WIN) && \
(!defined(WEBRTC_MAC) || RTC_USE_NATIVE_MUTEX_ON_MAC)
const struct timespec ts_null = {0};
#endif
- while (AtomicOps::CompareAndSwap(&lock_acquired, 0, 1)) {
+ while (AtomicOps::CompareAndSwap(&lock_acquired_, 0, 1)) {
#if defined(WEBRTC_WIN)
::Sleep(0);
#elif defined(WEBRTC_MAC) && !RTC_USE_NATIVE_MUTEX_ON_MAC
@@ -233,16 +233,12 @@
}
}
-void GlobalLockPod::Unlock() {
- int old_value = AtomicOps::CompareAndSwap(&lock_acquired, 1, 0);
+void GlobalLock::Unlock() {
+ int old_value = AtomicOps::CompareAndSwap(&lock_acquired_, 1, 0);
RTC_DCHECK_EQ(1, old_value) << "Unlock called without calling Lock first";
}
-GlobalLock::GlobalLock() {
- lock_acquired = 0;
-}
-
-GlobalLockScope::GlobalLockScope(GlobalLockPod* lock) : lock_(lock) {
+GlobalLockScope::GlobalLockScope(GlobalLock* lock) : lock_(lock) {
lock_->Lock();
}
diff --git a/rtc_base/critical_section.h b/rtc_base/critical_section.h
index f9047a6..a13721e 100644
--- a/rtc_base/critical_section.h
+++ b/rtc_base/critical_section.h
@@ -94,31 +94,26 @@
RTC_DISALLOW_COPY_AND_ASSIGN(CritScope);
};
-// A POD lock used to protect global variables. Do NOT use for other purposes.
-// No custom constructor or private data member should be added.
-class RTC_LOCKABLE GlobalLockPod {
+// A lock used to protect global variables. Do NOT use for other purposes.
+class RTC_LOCKABLE GlobalLock {
public:
- void Lock() RTC_EXCLUSIVE_LOCK_FUNCTION();
+ constexpr GlobalLock() : lock_acquired_(0) {}
+ void Lock() RTC_EXCLUSIVE_LOCK_FUNCTION();
void Unlock() RTC_UNLOCK_FUNCTION();
- volatile int lock_acquired;
-};
-
-class GlobalLock : public GlobalLockPod {
- public:
- GlobalLock();
+ private:
+ volatile int lock_acquired_;
};
// GlobalLockScope, for serializing execution through a scope.
class RTC_SCOPED_LOCKABLE GlobalLockScope {
public:
- explicit GlobalLockScope(GlobalLockPod* lock)
- RTC_EXCLUSIVE_LOCK_FUNCTION(lock);
+ explicit GlobalLockScope(GlobalLock* lock) RTC_EXCLUSIVE_LOCK_FUNCTION(lock);
~GlobalLockScope() RTC_UNLOCK_FUNCTION();
private:
- GlobalLockPod* const lock_;
+ GlobalLock* const lock_;
RTC_DISALLOW_COPY_AND_ASSIGN(GlobalLockScope);
};
diff --git a/rtc_base/critical_section_unittest.cc b/rtc_base/critical_section_unittest.cc
index 04af949..e384e98 100644
--- a/rtc_base/critical_section_unittest.cc
+++ b/rtc_base/critical_section_unittest.cc
@@ -15,9 +15,11 @@
#include <memory>
#include <set>
+#include <type_traits>
#include <utility>
#include <vector>
+#include "absl/base/attributes.h"
#include "rtc_base/arraysize.h"
#include "rtc_base/atomic_ops.h"
#include "rtc_base/checks.h"
@@ -281,6 +283,13 @@
EXPECT_EQ(1, runner.shared_value());
}
+TEST(GlobalLockTest, CanHaveStaticStorageDuration) {
+ static_assert(std::is_trivially_destructible<GlobalLock>::value, "");
+ ABSL_CONST_INIT static GlobalLock global_lock;
+ global_lock.Lock();
+ global_lock.Unlock();
+}
+
TEST(GlobalLockTest, Basic) {
// Create and start lots of threads.
LockRunner<GlobalLock> runner;
diff --git a/rtc_base/system/thread_registry.cc b/rtc_base/system/thread_registry.cc
index 8d7cd58..8660544 100644
--- a/rtc_base/system/thread_registry.cc
+++ b/rtc_base/system/thread_registry.cc
@@ -30,7 +30,7 @@
// The map of registered threads, and the lock that protects it. We create the
// map on first use, and never destroy it.
-ABSL_CONST_INIT rtc::GlobalLockPod g_thread_registry_lock = {};
+ABSL_CONST_INIT rtc::GlobalLock g_thread_registry_lock;
ABSL_CONST_INIT std::map<const ScopedRegisterThreadForDebugging*, ThreadData>*
g_registered_threads = nullptr;
diff --git a/sdk/android/BUILD.gn b/sdk/android/BUILD.gn
index 8b14286..f6fd462 100644
--- a/sdk/android/BUILD.gn
+++ b/sdk/android/BUILD.gn
@@ -975,6 +975,7 @@
"../../rtc_base:criticalsection",
"../../rtc_base:logging",
"../../rtc_base:stringutils",
+ "//third_party/abseil-cpp/absl/base:core_headers",
]
}
diff --git a/sdk/android/native_api/stacktrace/stacktrace.cc b/sdk/android/native_api/stacktrace/stacktrace.cc
index 64adf44..df1ee64 100644
--- a/sdk/android/native_api/stacktrace/stacktrace.cc
+++ b/sdk/android/native_api/stacktrace/stacktrace.cc
@@ -26,6 +26,7 @@
#undef DS
#endif
+#include "absl/base/attributes.h"
#include "rtc_base/critical_section.h"
#include "rtc_base/logging.h"
#include "rtc_base/strings/string_builder.h"
@@ -91,7 +92,7 @@
};
// Global lock to ensure only one thread gets interrupted at a time.
-rtc::GlobalLockPod g_signal_handler_lock;
+ABSL_CONST_INIT rtc::GlobalLock g_signal_handler_lock;
// Argument passed to the ThreadSignalHandler() from the sampling thread to the
// sampled (stopped) thread. This value is set just before sending signal to the
// thread and reset when handler is done.
