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-rw-r--r--third_party/abseil_cpp/absl/synchronization/mutex_benchmark.cc224
1 files changed, 0 insertions, 224 deletions
diff --git a/third_party/abseil_cpp/absl/synchronization/mutex_benchmark.cc b/third_party/abseil_cpp/absl/synchronization/mutex_benchmark.cc
deleted file mode 100644
index 933ea14f8f1d..000000000000
--- a/third_party/abseil_cpp/absl/synchronization/mutex_benchmark.cc
+++ /dev/null
@@ -1,224 +0,0 @@
-// 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.
-
-#include <cstdint>
-#include <mutex>  // NOLINT(build/c++11)
-#include <vector>
-
-#include "absl/base/config.h"
-#include "absl/base/internal/cycleclock.h"
-#include "absl/base/internal/spinlock.h"
-#include "absl/synchronization/blocking_counter.h"
-#include "absl/synchronization/internal/thread_pool.h"
-#include "absl/synchronization/mutex.h"
-#include "benchmark/benchmark.h"
-
-namespace {
-
-void BM_Mutex(benchmark::State& state) {
-  static absl::Mutex* mu = new absl::Mutex;
-  for (auto _ : state) {
-    absl::MutexLock lock(mu);
-  }
-}
-BENCHMARK(BM_Mutex)->UseRealTime()->Threads(1)->ThreadPerCpu();
-
-static void DelayNs(int64_t ns, int* data) {
-  int64_t end = absl::base_internal::CycleClock::Now() +
-                ns * absl::base_internal::CycleClock::Frequency() / 1e9;
-  while (absl::base_internal::CycleClock::Now() < end) {
-    ++(*data);
-    benchmark::DoNotOptimize(*data);
-  }
-}
-
-template <typename MutexType>
-class RaiiLocker {
- public:
-  explicit RaiiLocker(MutexType* mu) : mu_(mu) { mu_->Lock(); }
-  ~RaiiLocker() { mu_->Unlock(); }
- private:
-  MutexType* mu_;
-};
-
-template <>
-class RaiiLocker<std::mutex> {
- public:
-  explicit RaiiLocker(std::mutex* mu) : mu_(mu) { mu_->lock(); }
-  ~RaiiLocker() { mu_->unlock(); }
- private:
-  std::mutex* mu_;
-};
-
-template <typename MutexType>
-void BM_Contended(benchmark::State& state) {
-  struct Shared {
-    MutexType mu;
-    int data = 0;
-  };
-  static auto* shared = new Shared;
-  int local = 0;
-  for (auto _ : state) {
-    // Here we model both local work outside of the critical section as well as
-    // some work inside of the critical section. The idea is to capture some
-    // more or less realisitic contention levels.
-    // If contention is too low, the benchmark won't measure anything useful.
-    // If contention is unrealistically high, the benchmark will favor
-    // bad mutex implementations that block and otherwise distract threads
-    // from the mutex and shared state for as much as possible.
-    // To achieve this amount of local work is multiplied by number of threads
-    // to keep ratio between local work and critical section approximately
-    // equal regardless of number of threads.
-    DelayNs(100 * state.threads, &local);
-    RaiiLocker<MutexType> locker(&shared->mu);
-    DelayNs(state.range(0), &shared->data);
-  }
-}
-
-BENCHMARK_TEMPLATE(BM_Contended, absl::Mutex)
-    ->UseRealTime()
-    // ThreadPerCpu poorly handles non-power-of-two CPU counts.
-    ->Threads(1)
-    ->Threads(2)
-    ->Threads(4)
-    ->Threads(6)
-    ->Threads(8)
-    ->Threads(12)
-    ->Threads(16)
-    ->Threads(24)
-    ->Threads(32)
-    ->Threads(48)
-    ->Threads(64)
-    ->Threads(96)
-    ->Threads(128)
-    ->Threads(192)
-    ->Threads(256)
-    // Some empirically chosen amounts of work in critical section.
-    // 1 is low contention, 200 is high contention and few values in between.
-    ->Arg(1)
-    ->Arg(20)
-    ->Arg(50)
-    ->Arg(200);
-
-BENCHMARK_TEMPLATE(BM_Contended, absl::base_internal::SpinLock)
-    ->UseRealTime()
-    // ThreadPerCpu poorly handles non-power-of-two CPU counts.
-    ->Threads(1)
-    ->Threads(2)
-    ->Threads(4)
-    ->Threads(6)
-    ->Threads(8)
-    ->Threads(12)
-    ->Threads(16)
-    ->Threads(24)
-    ->Threads(32)
-    ->Threads(48)
-    ->Threads(64)
-    ->Threads(96)
-    ->Threads(128)
-    ->Threads(192)
-    ->Threads(256)
-    // Some empirically chosen amounts of work in critical section.
-    // 1 is low contention, 200 is high contention and few values in between.
-    ->Arg(1)
-    ->Arg(20)
-    ->Arg(50)
-    ->Arg(200);
-
-BENCHMARK_TEMPLATE(BM_Contended, std::mutex)
-    ->UseRealTime()
-    // ThreadPerCpu poorly handles non-power-of-two CPU counts.
-    ->Threads(1)
-    ->Threads(2)
-    ->Threads(4)
-    ->Threads(6)
-    ->Threads(8)
-    ->Threads(12)
-    ->Threads(16)
-    ->Threads(24)
-    ->Threads(32)
-    ->Threads(48)
-    ->Threads(64)
-    ->Threads(96)
-    ->Threads(128)
-    ->Threads(192)
-    ->Threads(256)
-    // Some empirically chosen amounts of work in critical section.
-    // 1 is low contention, 200 is high contention and few values in between.
-    ->Arg(1)
-    ->Arg(20)
-    ->Arg(50)
-    ->Arg(200);
-
-// Measure the overhead of conditions on mutex release (when they must be
-// evaluated).  Mutex has (some) support for equivalence classes allowing
-// Conditions with the same function/argument to potentially not be multiply
-// evaluated.
-//
-// num_classes==0 is used for the special case of every waiter being distinct.
-void BM_ConditionWaiters(benchmark::State& state) {
-  int num_classes = state.range(0);
-  int num_waiters = state.range(1);
-
-  struct Helper {
-    static void Waiter(absl::BlockingCounter* init, absl::Mutex* m, int* p) {
-      init->DecrementCount();
-      m->LockWhen(absl::Condition(
-          static_cast<bool (*)(int*)>([](int* v) { return *v == 0; }), p));
-      m->Unlock();
-    }
-  };
-
-  if (num_classes == 0) {
-    // No equivalence classes.
-    num_classes = num_waiters;
-  }
-
-  absl::BlockingCounter init(num_waiters);
-  absl::Mutex mu;
-  std::vector<int> equivalence_classes(num_classes, 1);
-
-  // Must be declared last to be destroyed first.
-  absl::synchronization_internal::ThreadPool pool(num_waiters);
-
-  for (int i = 0; i < num_waiters; i++) {
-    // Mutex considers Conditions with the same function and argument
-    // to be equivalent.
-    pool.Schedule([&, i] {
-      Helper::Waiter(&init, &mu, &equivalence_classes[i % num_classes]);
-    });
-  }
-  init.Wait();
-
-  for (auto _ : state) {
-    mu.Lock();
-    mu.Unlock();  // Each unlock requires Condition evaluation for our waiters.
-  }
-
-  mu.Lock();
-  for (int i = 0; i < num_classes; i++) {
-    equivalence_classes[i] = 0;
-  }
-  mu.Unlock();
-}
-
-// Some configurations have higher thread limits than others.
-#if defined(__linux__) && !defined(ABSL_HAVE_THREAD_SANITIZER)
-constexpr int kMaxConditionWaiters = 8192;
-#else
-constexpr int kMaxConditionWaiters = 1024;
-#endif
-BENCHMARK(BM_ConditionWaiters)->RangePair(0, 2, 1, kMaxConditionWaiters);
-
-}  // namespace