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authorAndroid Build Coastguard Worker <android-build-coastguard-worker@google.com>2022-04-28 16:00:45 +0000
committerAndroid Build Coastguard Worker <android-build-coastguard-worker@google.com>2022-04-28 16:00:45 +0000
commite5224b792dcb4d38827ebec74cedbefa3cf78018 (patch)
tree2ce94d7f0804ccb77d1fa9b2a1bca00eecdff1e2 /third_party/abseil-cpp/absl/profiling/internal/periodic_sampler.cc
parent88178ab82d402f04f48986d07f10b10aea9852a8 (diff)
parent7563023510bf04108a954596ea9393a4c11ac279 (diff)
downloadwebrtc-e5224b792dcb4d38827ebec74cedbefa3cf78018.tar.gz
Snap for 8512216 from 7563023510bf04108a954596ea9393a4c11ac279 to tm-frc-media-releaset_frc_med_330443030android13-frc-media-release
Change-Id: I08bed87f39763e4984489981fea9de450012cf88
Diffstat (limited to 'third_party/abseil-cpp/absl/profiling/internal/periodic_sampler.cc')
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diff --git a/third_party/abseil-cpp/absl/profiling/internal/periodic_sampler.cc b/third_party/abseil-cpp/absl/profiling/internal/periodic_sampler.cc
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+++ b/third_party/abseil-cpp/absl/profiling/internal/periodic_sampler.cc
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+// Copyright 2019 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/profiling/internal/periodic_sampler.h"
+
+#include <atomic>
+
+#include "absl/profiling/internal/exponential_biased.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace profiling_internal {
+
+int64_t PeriodicSamplerBase::GetExponentialBiased(int period) noexcept {
+ return rng_.GetStride(period);
+}
+
+bool PeriodicSamplerBase::SubtleConfirmSample() noexcept {
+ int current_period = period();
+
+ // Deal with period case 0 (always off) and 1 (always on)
+ if (ABSL_PREDICT_FALSE(current_period < 2)) {
+ stride_ = 0;
+ return current_period == 1;
+ }
+
+ // Check if this is the first call to Sample()
+ if (ABSL_PREDICT_FALSE(stride_ == 1)) {
+ stride_ = static_cast<uint64_t>(-GetExponentialBiased(current_period));
+ if (static_cast<int64_t>(stride_) < -1) {
+ ++stride_;
+ return false;
+ }
+ }
+
+ stride_ = static_cast<uint64_t>(-GetExponentialBiased(current_period));
+ return true;
+}
+
+} // namespace profiling_internal
+ABSL_NAMESPACE_END
+} // namespace absl