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Diffstat (limited to 'third_party/abseil-cpp/absl/container/internal/hashtablez_sampler.cc')
-rw-r--r--third_party/abseil-cpp/absl/container/internal/hashtablez_sampler.cc129
1 files changed, 25 insertions, 104 deletions
diff --git a/third_party/abseil-cpp/absl/container/internal/hashtablez_sampler.cc b/third_party/abseil-cpp/absl/container/internal/hashtablez_sampler.cc
index 5644725178..40cce0479e 100644
--- a/third_party/abseil-cpp/absl/container/internal/hashtablez_sampler.cc
+++ b/third_party/abseil-cpp/absl/container/internal/hashtablez_sampler.cc
@@ -21,10 +21,11 @@
#include <limits>
#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/profiling/internal/exponential_biased.h"
+#include "absl/profiling/internal/sample_recorder.h"
#include "absl/synchronization/mutex.h"
namespace absl {
@@ -37,10 +38,9 @@ ABSL_CONST_INIT std::atomic<bool> g_hashtablez_enabled{
false
};
ABSL_CONST_INIT std::atomic<int32_t> g_hashtablez_sample_parameter{1 << 10};
-ABSL_CONST_INIT std::atomic<int32_t> g_hashtablez_max_samples{1 << 20};
#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
-ABSL_PER_THREAD_TLS_KEYWORD absl::base_internal::ExponentialBiased
+ABSL_PER_THREAD_TLS_KEYWORD absl::profiling_internal::ExponentialBiased
g_exponential_biased_generator;
#endif
@@ -50,16 +50,14 @@ ABSL_PER_THREAD_TLS_KEYWORD absl::base_internal::ExponentialBiased
ABSL_PER_THREAD_TLS_KEYWORD int64_t global_next_sample = 0;
#endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
-HashtablezSampler& HashtablezSampler::Global() {
+HashtablezSampler& GlobalHashtablezSampler() {
static auto* sampler = new HashtablezSampler();
return *sampler;
}
-HashtablezSampler::DisposeCallback HashtablezSampler::SetDisposeCallback(
- DisposeCallback f) {
- return dispose_.exchange(f, std::memory_order_relaxed);
-}
-
+// TODO(bradleybear): The comments at this constructors declaration say that the
+// fields are not initialized, but this definition does initialize the fields.
+// Something needs to be cleaned up.
HashtablezInfo::HashtablezInfo() { PrepareForSampling(); }
HashtablezInfo::~HashtablezInfo() = default;
@@ -67,10 +65,13 @@ 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);
+ hashes_bitwise_xor.store(0, std::memory_order_relaxed);
+ max_reserve.store(0, std::memory_order_relaxed);
create_time = absl::Now();
// The inliner makes hardcoded skip_count difficult (especially when combined
@@ -78,93 +79,6 @@ void HashtablezInfo::PrepareForSampling() {
// 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<void(const HashtablezInfo& stack)>& 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() {
@@ -179,16 +93,20 @@ static bool ShouldForceSampling() {
if (ABSL_PREDICT_TRUE(state == kDontForce)) return false;
if (state == kUninitialized) {
- state = AbslContainerInternalSampleEverything() ? kForce : kDontForce;
+ state = ABSL_INTERNAL_C_SYMBOL(AbslContainerInternalSampleEverything)()
+ ? kForce
+ : kDontForce;
global_state.store(state, std::memory_order_relaxed);
}
return state == kForce;
}
-HashtablezInfo* SampleSlow(int64_t* next_sample) {
+HashtablezInfo* SampleSlow(int64_t* next_sample, size_t inline_element_size) {
if (ABSL_PREDICT_FALSE(ShouldForceSampling())) {
*next_sample = 1;
- return HashtablezSampler::Global().Register();
+ HashtablezInfo* result = GlobalHashtablezSampler().Register();
+ result->inline_element_size = inline_element_size;
+ return result;
}
#if !defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
@@ -210,15 +128,17 @@ HashtablezInfo* SampleSlow(int64_t* next_sample) {
// that case.
if (first) {
if (ABSL_PREDICT_TRUE(--*next_sample > 0)) return nullptr;
- return SampleSlow(next_sample);
+ return SampleSlow(next_sample, inline_element_size);
}
- return HashtablezSampler::Global().Register();
+ HashtablezInfo* result = GlobalHashtablezSampler().Register();
+ result->inline_element_size = inline_element_size;
+ return result;
#endif
}
void UnsampleSlow(HashtablezInfo* info) {
- HashtablezSampler::Global().Unregister(info);
+ GlobalHashtablezSampler().Unregister(info);
}
void RecordInsertSlow(HashtablezInfo* info, size_t hash,
@@ -226,7 +146,7 @@ void RecordInsertSlow(HashtablezInfo* info, size_t hash,
// 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 SWISSTABLE_HAVE_SSE2
+#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2
probe_length /= 16;
#else
probe_length /= 8;
@@ -234,6 +154,7 @@ void RecordInsertSlow(HashtablezInfo* info, size_t hash,
info->hashes_bitwise_and.fetch_and(hash, std::memory_order_relaxed);
info->hashes_bitwise_or.fetch_or(hash, std::memory_order_relaxed);
+ info->hashes_bitwise_xor.fetch_xor(hash, std::memory_order_relaxed);
info->max_probe_length.store(
std::max(info->max_probe_length.load(std::memory_order_relaxed),
probe_length),
@@ -257,7 +178,7 @@ void SetHashtablezSampleParameter(int32_t rate) {
void SetHashtablezMaxSamples(int32_t max) {
if (max > 0) {
- g_hashtablez_max_samples.store(max, std::memory_order_release);
+ GlobalHashtablezSampler().SetMaxSamples(max);
} else {
ABSL_RAW_LOG(ERROR, "Invalid hashtablez max samples: %lld",
static_cast<long long>(max)); // NOLINT(runtime/int)
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-23 12:07:30 +0000