diff options
Diffstat (limited to 'src/third_party/abseil-cpp-master/abseil-cpp/absl/base/internal/thread_identity.cc')
| -rw-r--r-- | src/third_party/abseil-cpp-master/abseil-cpp/absl/base/internal/thread_identity.cc | 36 |
1 files changed, 29 insertions, 7 deletions
diff --git a/src/third_party/abseil-cpp-master/abseil-cpp/absl/base/internal/thread_identity.cc b/src/third_party/abseil-cpp-master/abseil-cpp/absl/base/internal/thread_identity.cc index cff9c1b4f4d..6ea010ed0d3 100644 --- a/src/third_party/abseil-cpp-master/abseil-cpp/absl/base/internal/thread_identity.cc +++ b/src/third_party/abseil-cpp-master/abseil-cpp/absl/base/internal/thread_identity.cc @@ -4,7 +4,7 @@ // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // -// http://www.apache.org/licenses/LICENSE-2.0 +// https://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, @@ -23,11 +23,13 @@ #include <cassert> #include <memory> +#include "absl/base/attributes.h" #include "absl/base/call_once.h" #include "absl/base/internal/raw_logging.h" #include "absl/base/internal/spinlock.h" namespace absl { +ABSL_NAMESPACE_BEGIN namespace base_internal { #if ABSL_THREAD_IDENTITY_MODE != ABSL_THREAD_IDENTITY_MODE_USE_CPP11 @@ -52,10 +54,17 @@ void AllocateThreadIdentityKey(ThreadIdentityReclaimerFunction reclaimer) { // exist within a process (via dlopen() or similar), references to // thread_identity_ptr from each instance of the code will refer to // *different* instances of this ptr. -#ifdef __GNUC__ +// Apple platforms have the visibility attribute, but issue a compile warning +// that protected visibility is unsupported. +#if ABSL_HAVE_ATTRIBUTE(visibility) && !defined(__APPLE__) __attribute__((visibility("protected"))) -#endif // __GNUC__ - ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity* thread_identity_ptr; +#endif // ABSL_HAVE_ATTRIBUTE(visibility) && !defined(__APPLE__) +#if ABSL_PER_THREAD_TLS +// Prefer __thread to thread_local as benchmarks indicate it is a bit faster. +ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity* thread_identity_ptr = nullptr; +#elif defined(ABSL_HAVE_THREAD_LOCAL) +thread_local ThreadIdentity* thread_identity_ptr = nullptr; +#endif // ABSL_PER_THREAD_TLS #endif // TLS or CPP11 void SetCurrentThreadIdentity( @@ -69,8 +78,8 @@ void SetCurrentThreadIdentity( absl::call_once(init_thread_identity_key_once, AllocateThreadIdentityKey, reclaimer); -#ifdef __EMSCRIPTEN__ - // Emscripten PThread implementation does not support signals. +#if defined(__EMSCRIPTEN__) || defined(__MINGW32__) + // Emscripten and MinGW pthread implementations does not support signals. // See https://kripken.github.io/emscripten-site/docs/porting/pthreads.html // for more information. pthread_setspecific(thread_identity_pthread_key, @@ -89,7 +98,7 @@ void SetCurrentThreadIdentity( pthread_setspecific(thread_identity_pthread_key, reinterpret_cast<void*>(identity)); pthread_sigmask(SIG_SETMASK, &curr_signals, nullptr); -#endif // !__EMSCRIPTEN__ +#endif // !__EMSCRIPTEN__ && !__MINGW32__ #elif ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS // NOTE: Not async-safe. But can be open-coded. @@ -107,6 +116,18 @@ void SetCurrentThreadIdentity( #endif } +#if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS || \ + ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11 + +// Please see the comment on `CurrentThreadIdentityIfPresent` in +// thread_identity.h. Because DLLs cannot expose thread_local variables in +// headers, we opt for the correct-but-slower option of placing the definition +// of this function only in a translation unit inside DLL. +#if defined(ABSL_BUILD_DLL) || defined(ABSL_CONSUME_DLL) +ThreadIdentity* CurrentThreadIdentityIfPresent() { return thread_identity_ptr; } +#endif +#endif + void ClearCurrentThreadIdentity() { #if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS || \ ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11 @@ -130,4 +151,5 @@ ThreadIdentity* CurrentThreadIdentityIfPresent() { #endif } // namespace base_internal +ABSL_NAMESPACE_END } // namespace absl |