diff options
author | Devtools Arcadia <[email protected]> | 2022-02-07 18:08:42 +0300 |
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committer | Devtools Arcadia <[email protected]> | 2022-02-07 18:08:42 +0300 |
commit | 1110808a9d39d4b808aef724c861a2e1a38d2a69 (patch) | |
tree | e26c9fed0de5d9873cce7e00bc214573dc2195b7 /contrib/restricted/abseil-cpp-tstring/y_absl/synchronization/internal/per_thread_sem.cc |
intermediate changes
ref:cde9a383711a11544ce7e107a78147fb96cc4029
Diffstat (limited to 'contrib/restricted/abseil-cpp-tstring/y_absl/synchronization/internal/per_thread_sem.cc')
-rw-r--r-- | contrib/restricted/abseil-cpp-tstring/y_absl/synchronization/internal/per_thread_sem.cc | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/contrib/restricted/abseil-cpp-tstring/y_absl/synchronization/internal/per_thread_sem.cc b/contrib/restricted/abseil-cpp-tstring/y_absl/synchronization/internal/per_thread_sem.cc new file mode 100644 index 00000000000..3e40e812a9a --- /dev/null +++ b/contrib/restricted/abseil-cpp-tstring/y_absl/synchronization/internal/per_thread_sem.cc @@ -0,0 +1,106 @@ +// Copyright 2017 The Abseil Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// 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, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// This file is a no-op if the required LowLevelAlloc support is missing. +#include "y_absl/base/internal/low_level_alloc.h" +#ifndef ABSL_LOW_LEVEL_ALLOC_MISSING + +#include "y_absl/synchronization/internal/per_thread_sem.h" + +#include <atomic> + +#include "y_absl/base/attributes.h" +#include "y_absl/base/internal/thread_identity.h" +#include "y_absl/synchronization/internal/waiter.h" + +namespace y_absl { +ABSL_NAMESPACE_BEGIN +namespace synchronization_internal { + +void PerThreadSem::SetThreadBlockedCounter(std::atomic<int> *counter) { + base_internal::ThreadIdentity *identity; + identity = GetOrCreateCurrentThreadIdentity(); + identity->blocked_count_ptr = counter; +} + +std::atomic<int> *PerThreadSem::GetThreadBlockedCounter() { + base_internal::ThreadIdentity *identity; + identity = GetOrCreateCurrentThreadIdentity(); + return identity->blocked_count_ptr; +} + +void PerThreadSem::Init(base_internal::ThreadIdentity *identity) { + new (Waiter::GetWaiter(identity)) Waiter(); + identity->ticker.store(0, std::memory_order_relaxed); + identity->wait_start.store(0, std::memory_order_relaxed); + identity->is_idle.store(false, std::memory_order_relaxed); +} + +void PerThreadSem::Destroy(base_internal::ThreadIdentity *identity) { + Waiter::GetWaiter(identity)->~Waiter(); +} + +void PerThreadSem::Tick(base_internal::ThreadIdentity *identity) { + const int ticker = + identity->ticker.fetch_add(1, std::memory_order_relaxed) + 1; + const int wait_start = identity->wait_start.load(std::memory_order_relaxed); + const bool is_idle = identity->is_idle.load(std::memory_order_relaxed); + if (wait_start && (ticker - wait_start > Waiter::kIdlePeriods) && !is_idle) { + // Wakeup the waiting thread since it is time for it to become idle. + Waiter::GetWaiter(identity)->Poke(); + } +} + +} // namespace synchronization_internal +ABSL_NAMESPACE_END +} // namespace y_absl + +extern "C" { + +ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalPerThreadSemPost)( + y_absl::base_internal::ThreadIdentity *identity) { + y_absl::synchronization_internal::Waiter::GetWaiter(identity)->Post(); +} + +ABSL_ATTRIBUTE_WEAK bool ABSL_INTERNAL_C_SYMBOL(AbslInternalPerThreadSemWait)( + y_absl::synchronization_internal::KernelTimeout t) { + bool timeout = false; + y_absl::base_internal::ThreadIdentity *identity; + identity = y_absl::synchronization_internal::GetOrCreateCurrentThreadIdentity(); + + // Ensure wait_start != 0. + int ticker = identity->ticker.load(std::memory_order_relaxed); + identity->wait_start.store(ticker ? ticker : 1, std::memory_order_relaxed); + identity->is_idle.store(false, std::memory_order_relaxed); + + if (identity->blocked_count_ptr != nullptr) { + // Increment count of threads blocked in a given thread pool. + identity->blocked_count_ptr->fetch_add(1, std::memory_order_relaxed); + } + + timeout = + !y_absl::synchronization_internal::Waiter::GetWaiter(identity)->Wait(t); + + if (identity->blocked_count_ptr != nullptr) { + identity->blocked_count_ptr->fetch_sub(1, std::memory_order_relaxed); + } + + identity->is_idle.store(false, std::memory_order_relaxed); + identity->wait_start.store(0, std::memory_order_relaxed); + return !timeout; +} + +} // extern "C" + +#endif // ABSL_LOW_LEVEL_ALLOC_MISSING |