Export of internal Abseil changes

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5b9d5ce21074c0541432555d383d1b9c5898b553 by Gennadiy Rozental <rogeeff@google.com>:

Convert FlagSaver into public API

PiperOrigin-RevId: 314799739

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5f796c9862b1177f161f4b10fe1a84698ebbb5cf by Abseil Team <absl-team@google.com>:

Google-internal changes only.

PiperOrigin-RevId: 314786474

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67f2ae0ac5ae73bcd9d57a058ac4fea8fc1243ba by Gennadiy Rozental <rogeeff@google.com>:

Makes sure stacktrace_generic is only used with glibc.

Fixes #701

PiperOrigin-RevId: 314726944

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efb1ef3636b0698b79d3ee3590f12c4dff32a3cb by Samuel Benzaquen <sbenza@google.com>:

Take the bits into account when reserving the space for the operation, not just
the exponent.

PiperOrigin-RevId: 314622744
GitOrigin-RevId: 5b9d5ce21074c0541432555d383d1b9c5898b553
Change-Id: I080a5e333e2dc1545b5aa0417882f7ac7116a20c

1 files changed, 7 insertions, 0 deletions

diff --git a/absl/synchronization/mutex.cc b/absl/synchronization/mutex.cc
index 1f8a696e..36c93d5f 100644
--- a/absl/synchronization/mutex.cc
+++ b/absl/synchronization/mutex.cc
@@ -58,6 +58,7 @@
 
 using absl::base_internal::CurrentThreadIdentityIfPresent;
 using absl::base_internal::PerThreadSynch;
+using absl::base_internal::SchedulingGuard;
 using absl::base_internal::ThreadIdentity;
 using absl::synchronization_internal::GetOrCreateCurrentThreadIdentity;
 using absl::synchronization_internal::GraphCycles;
@@ -1108,6 +1109,7 @@ void Mutex::TryRemove(PerThreadSynch *s) {
 // on the mutex queue.  In this case, remove "s" from the queue and return
 // true, otherwise return false.
 ABSL_XRAY_LOG_ARGS(1) void Mutex::Block(PerThreadSynch *s) {
+  SchedulingGuard::ScopedDisable disable_rescheduling;
   while (s->state.load(std::memory_order_acquire) == PerThreadSynch::kQueued) {
     if (!DecrementSynchSem(this, s, s->waitp->timeout)) {
       // After a timeout, we go into a spin loop until we remove ourselves
@@ -1897,6 +1899,7 @@ static void CheckForMutexCorruption(intptr_t v, const char* label) {
 }
 
 void Mutex::LockSlowLoop(SynchWaitParams *waitp, int flags) {
+  SchedulingGuard::ScopedDisable disable_rescheduling;
   int c = 0;
   intptr_t v = mu_.load(std::memory_order_relaxed);
   if ((v & kMuEvent) != 0) {
@@ -2016,6 +2019,7 @@ void Mutex::LockSlowLoop(SynchWaitParams *waitp, int flags) {
 // or it is in the process of blocking on a condition variable; it must requeue
 // itself on the mutex/condvar to wait for its condition to become true.
 ABSL_ATTRIBUTE_NOINLINE void Mutex::UnlockSlow(SynchWaitParams *waitp) {
+  SchedulingGuard::ScopedDisable disable_rescheduling;
   intptr_t v = mu_.load(std::memory_order_relaxed);
   this->AssertReaderHeld();
   CheckForMutexCorruption(v, "Unlock");
@@ -2331,6 +2335,7 @@ void Mutex::Trans(MuHow how) {
 // It will later acquire the mutex with high probability.  Otherwise, we
 // enqueue thread w on this mutex.
 void Mutex::Fer(PerThreadSynch *w) {
+  SchedulingGuard::ScopedDisable disable_rescheduling;
   int c = 0;
   ABSL_RAW_CHECK(w->waitp->cond == nullptr,
                  "Mutex::Fer while waiting on Condition");
@@ -2429,6 +2434,7 @@ CondVar::~CondVar() {
 
 // Remove thread s from the list of waiters on this condition variable.
 void CondVar::Remove(PerThreadSynch *s) {
+  SchedulingGuard::ScopedDisable disable_rescheduling;
   intptr_t v;
   int c = 0;
   for (v = cv_.load(std::memory_order_relaxed);;
@@ -2589,6 +2595,7 @@ void CondVar::Wakeup(PerThreadSynch *w) {
 }
 
 void CondVar::Signal() {
+  SchedulingGuard::ScopedDisable disable_rescheduling;
   ABSL_TSAN_MUTEX_PRE_SIGNAL(nullptr, 0);
   intptr_t v;
   int c = 0;