Export of internal Abseil changes.

--
821196cfb2a3b943ffdc4c9e75daec92d7ffb28b by Abseil Team <absl-team@google.com>:

Performance improvements

PiperOrigin-RevId: 212668992

--
704858e2e767016bad27d53eec01d9d48e546b23 by Abseil Team <absl-team@google.com>:

Low-level Portability enchancements for Abseil Mutex on WebAssembly.

Emscripten Pthreads do not use signals, so remove use of pthread_sigmask or
other async-signal-safe related handling code.

PiperOrigin-RevId: 212527958

--
be3e38cb4d493b755132d20c8c2d1a51e45d5449 by Jon Cohen <cohenjon@google.com>:

Internal change.

PiperOrigin-RevId: 212523797
GitOrigin-RevId: 821196cfb2a3b943ffdc4c9e75daec92d7ffb28b
Change-Id: I5694e23e4e09364a15dd6fc4e2e3f15e38835687
This commit is contained in:
Abseil Team 2018-09-12 11:03:25 -07:00 committed by Gennadiy Civil
parent 02451914b9
commit 8ff1374008
9 changed files with 198 additions and 170 deletions

View file

@ -68,6 +68,14 @@ void SetCurrentThreadIdentity(
// NOTE: Not async-safe. But can be open-coded.
absl::call_once(init_thread_identity_key_once, AllocateThreadIdentityKey,
reclaimer);
#ifdef __EMSCRIPTEN__
// Emscripten PThread implementation does not support signals.
// See https://kripken.github.io/emscripten-site/docs/porting/pthreads.html
// for more information.
pthread_setspecific(thread_identity_pthread_key,
reinterpret_cast<void*>(identity));
#else
// We must mask signals around the call to setspecific as with current glibc,
// a concurrent getspecific (needed for GetCurrentThreadIdentityIfPresent())
// may zero our value.
@ -81,6 +89,8 @@ void SetCurrentThreadIdentity(
pthread_setspecific(thread_identity_pthread_key,
reinterpret_cast<void*>(identity));
pthread_sigmask(SIG_SETMASK, &curr_signals, nullptr);
#endif // !__EMSCRIPTEN__
#elif ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS
// NOTE: Not async-safe. But can be open-coded.
absl::call_once(init_thread_identity_key_once, AllocateThreadIdentityKey,