From 5aa5d282eac56a21e74611c1cdbaa97bb5db2dca Mon Sep 17 00:00:00 2001 From: Vincent Ambo Date: Tue, 8 Feb 2022 02:05:36 +0300 Subject: chore(3p/abseil_cpp): unvendor abseil_cpp we weren't actually using these sources anymore, okay? Change-Id: If701571d9716de308d3512e1eb22c35db0877a66 Reviewed-on: https://cl.tvl.fyi/c/depot/+/5248 Tested-by: BuildkiteCI Reviewed-by: grfn Autosubmit: tazjin --- .../absl/container/internal/hashtablez_sampler.cc | 270 --------------------- 1 file changed, 270 deletions(-) delete mode 100644 third_party/abseil_cpp/absl/container/internal/hashtablez_sampler.cc (limited to 'third_party/abseil_cpp/absl/container/internal/hashtablez_sampler.cc') diff --git a/third_party/abseil_cpp/absl/container/internal/hashtablez_sampler.cc b/third_party/abseil_cpp/absl/container/internal/hashtablez_sampler.cc deleted file mode 100644 index e4484fbb1b43..000000000000 --- a/third_party/abseil_cpp/absl/container/internal/hashtablez_sampler.cc +++ /dev/null @@ -1,270 +0,0 @@ -// Copyright 2018 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 "absl/container/internal/hashtablez_sampler.h" - -#include -#include -#include -#include -#include - -#include "absl/base/attributes.h" -#include "absl/base/internal/exponential_biased.h" -#include "absl/container/internal/have_sse.h" -#include "absl/debugging/stacktrace.h" -#include "absl/memory/memory.h" -#include "absl/synchronization/mutex.h" - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace container_internal { -constexpr int HashtablezInfo::kMaxStackDepth; - -namespace { -ABSL_CONST_INIT std::atomic g_hashtablez_enabled{ - false -}; -ABSL_CONST_INIT std::atomic g_hashtablez_sample_parameter{1 << 10}; -ABSL_CONST_INIT std::atomic g_hashtablez_max_samples{1 << 20}; - -#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) -ABSL_PER_THREAD_TLS_KEYWORD absl::base_internal::ExponentialBiased - g_exponential_biased_generator; -#endif - -} // namespace - -#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) -ABSL_PER_THREAD_TLS_KEYWORD int64_t global_next_sample = 0; -#endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) - -HashtablezSampler& HashtablezSampler::Global() { - static auto* sampler = new HashtablezSampler(); - return *sampler; -} - -HashtablezSampler::DisposeCallback HashtablezSampler::SetDisposeCallback( - DisposeCallback f) { - return dispose_.exchange(f, std::memory_order_relaxed); -} - -HashtablezInfo::HashtablezInfo() { PrepareForSampling(); } -HashtablezInfo::~HashtablezInfo() = default; - -void HashtablezInfo::PrepareForSampling() { - capacity.store(0, std::memory_order_relaxed); - size.store(0, std::memory_order_relaxed); - num_erases.store(0, std::memory_order_relaxed); - num_rehashes.store(0, std::memory_order_relaxed); - max_probe_length.store(0, std::memory_order_relaxed); - total_probe_length.store(0, std::memory_order_relaxed); - hashes_bitwise_or.store(0, std::memory_order_relaxed); - hashes_bitwise_and.store(~size_t{}, std::memory_order_relaxed); - - create_time = absl::Now(); - // The inliner makes hardcoded skip_count difficult (especially when combined - // with LTO). We use the ability to exclude stacks by regex when encoding - // instead. - depth = absl::GetStackTrace(stack, HashtablezInfo::kMaxStackDepth, - /* skip_count= */ 0); - dead = nullptr; -} - -HashtablezSampler::HashtablezSampler() - : dropped_samples_(0), size_estimate_(0), all_(nullptr), dispose_(nullptr) { - absl::MutexLock l(&graveyard_.init_mu); - graveyard_.dead = &graveyard_; -} - -HashtablezSampler::~HashtablezSampler() { - HashtablezInfo* s = all_.load(std::memory_order_acquire); - while (s != nullptr) { - HashtablezInfo* next = s->next; - delete s; - s = next; - } -} - -void HashtablezSampler::PushNew(HashtablezInfo* sample) { - sample->next = all_.load(std::memory_order_relaxed); - while (!all_.compare_exchange_weak(sample->next, sample, - std::memory_order_release, - std::memory_order_relaxed)) { - } -} - -void HashtablezSampler::PushDead(HashtablezInfo* sample) { - if (auto* dispose = dispose_.load(std::memory_order_relaxed)) { - dispose(*sample); - } - - absl::MutexLock graveyard_lock(&graveyard_.init_mu); - absl::MutexLock sample_lock(&sample->init_mu); - sample->dead = graveyard_.dead; - graveyard_.dead = sample; -} - -HashtablezInfo* HashtablezSampler::PopDead() { - absl::MutexLock graveyard_lock(&graveyard_.init_mu); - - // The list is circular, so eventually it collapses down to - // graveyard_.dead == &graveyard_ - // when it is empty. - HashtablezInfo* sample = graveyard_.dead; - if (sample == &graveyard_) return nullptr; - - absl::MutexLock sample_lock(&sample->init_mu); - graveyard_.dead = sample->dead; - sample->PrepareForSampling(); - return sample; -} - -HashtablezInfo* HashtablezSampler::Register() { - int64_t size = size_estimate_.fetch_add(1, std::memory_order_relaxed); - if (size > g_hashtablez_max_samples.load(std::memory_order_relaxed)) { - size_estimate_.fetch_sub(1, std::memory_order_relaxed); - dropped_samples_.fetch_add(1, std::memory_order_relaxed); - return nullptr; - } - - HashtablezInfo* sample = PopDead(); - if (sample == nullptr) { - // Resurrection failed. Hire a new warlock. - sample = new HashtablezInfo(); - PushNew(sample); - } - - return sample; -} - -void HashtablezSampler::Unregister(HashtablezInfo* sample) { - PushDead(sample); - size_estimate_.fetch_sub(1, std::memory_order_relaxed); -} - -int64_t HashtablezSampler::Iterate( - const std::function& f) { - HashtablezInfo* s = all_.load(std::memory_order_acquire); - while (s != nullptr) { - absl::MutexLock l(&s->init_mu); - if (s->dead == nullptr) { - f(*s); - } - s = s->next; - } - - return dropped_samples_.load(std::memory_order_relaxed); -} - -static bool ShouldForceSampling() { - enum ForceState { - kDontForce, - kForce, - kUninitialized - }; - ABSL_CONST_INIT static std::atomic global_state{ - kUninitialized}; - ForceState state = global_state.load(std::memory_order_relaxed); - if (ABSL_PREDICT_TRUE(state == kDontForce)) return false; - - if (state == kUninitialized) { - state = AbslContainerInternalSampleEverything() ? kForce : kDontForce; - global_state.store(state, std::memory_order_relaxed); - } - return state == kForce; -} - -HashtablezInfo* SampleSlow(int64_t* next_sample) { - if (ABSL_PREDICT_FALSE(ShouldForceSampling())) { - *next_sample = 1; - return HashtablezSampler::Global().Register(); - } - -#if !defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) - *next_sample = std::numeric_limits::max(); - return nullptr; -#else - bool first = *next_sample < 0; - *next_sample = g_exponential_biased_generator.GetStride( - g_hashtablez_sample_parameter.load(std::memory_order_relaxed)); - // Small values of interval are equivalent to just sampling next time. - ABSL_ASSERT(*next_sample >= 1); - - // g_hashtablez_enabled can be dynamically flipped, we need to set a threshold - // low enough that we will start sampling in a reasonable time, so we just use - // the default sampling rate. - if (!g_hashtablez_enabled.load(std::memory_order_relaxed)) return nullptr; - - // We will only be negative on our first count, so we should just retry in - // that case. - if (first) { - if (ABSL_PREDICT_TRUE(--*next_sample > 0)) return nullptr; - return SampleSlow(next_sample); - } - - return HashtablezSampler::Global().Register(); -#endif -} - -void UnsampleSlow(HashtablezInfo* info) { - HashtablezSampler::Global().Unregister(info); -} - -void RecordInsertSlow(HashtablezInfo* info, size_t hash, - size_t distance_from_desired) { - // SwissTables probe in groups of 16, so scale this to count items probes and - // not offset from desired. - size_t probe_length = distance_from_desired; -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 - probe_length /= 16; -#else - probe_length /= 8; -#endif - - info->hashes_bitwise_and.fetch_and(hash, std::memory_order_relaxed); - info->hashes_bitwise_or.fetch_or(hash, std::memory_order_relaxed); - info->max_probe_length.store( - std::max(info->max_probe_length.load(std::memory_order_relaxed), - probe_length), - std::memory_order_relaxed); - info->total_probe_length.fetch_add(probe_length, std::memory_order_relaxed); - info->size.fetch_add(1, std::memory_order_relaxed); -} - -void SetHashtablezEnabled(bool enabled) { - g_hashtablez_enabled.store(enabled, std::memory_order_release); -} - -void SetHashtablezSampleParameter(int32_t rate) { - if (rate > 0) { - g_hashtablez_sample_parameter.store(rate, std::memory_order_release); - } else { - ABSL_RAW_LOG(ERROR, "Invalid hashtablez sample rate: %lld", - static_cast(rate)); // NOLINT(runtime/int) - } -} - -void SetHashtablezMaxSamples(int32_t max) { - if (max > 0) { - g_hashtablez_max_samples.store(max, std::memory_order_release); - } else { - ABSL_RAW_LOG(ERROR, "Invalid hashtablez max samples: %lld", - static_cast(max)); // NOLINT(runtime/int) - } -} - -} // namespace container_internal -ABSL_NAMESPACE_END -} // namespace absl -- cgit 1.4.1