--- /dev/null
+/*
+ *
+ * Copyright 2018 gRPC 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
+ *
+ * http://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 <grpc/support/port_platform.h>
+
+#include "src/core/ext/filters/client_channel/lb_policy/xds/xds_client_stats.h"
+
+#include <grpc/support/atm.h>
+#include <grpc/support/string_util.h>
+#include <string.h>
+
+namespace grpc_core {
+
+namespace {
+
+template <typename T>
+T GetAndResetCounter(Atomic<T>* from) {
+ return from->Exchange(0, MemoryOrder::RELAXED);
+}
+
+} // namespace
+
+//
+// XdsClientStats::LocalityStats::LoadMetric::Snapshot
+//
+
+bool XdsClientStats::LocalityStats::LoadMetric::Snapshot::IsAllZero() const {
+ return total_metric_value == 0 && num_requests_finished_with_metric == 0;
+}
+
+//
+// XdsClientStats::LocalityStats::LoadMetric
+//
+
+XdsClientStats::LocalityStats::LoadMetric::Snapshot
+XdsClientStats::LocalityStats::LoadMetric::GetSnapshotAndReset() {
+ Snapshot metric = {num_requests_finished_with_metric_, total_metric_value_};
+ num_requests_finished_with_metric_ = 0;
+ total_metric_value_ = 0;
+ return metric;
+}
+
+//
+// XdsClientStats::LocalityStats::Snapshot
+//
+
+bool XdsClientStats::LocalityStats::Snapshot::IsAllZero() {
+ if (total_successful_requests != 0 || total_requests_in_progress != 0 ||
+ total_error_requests != 0 || total_issued_requests != 0) {
+ return false;
+ }
+ for (auto& p : load_metric_stats) {
+ const LoadMetric::Snapshot& metric_value = p.second;
+ if (!metric_value.IsAllZero()) return false;
+ }
+ return true;
+}
+
+//
+// XdsClientStats::LocalityStats
+//
+
+XdsClientStats::LocalityStats::Snapshot
+XdsClientStats::LocalityStats::GetSnapshotAndReset() {
+ Snapshot snapshot = {
+ GetAndResetCounter(&total_successful_requests_),
+ // Don't reset total_requests_in_progress because it's not
+ // related to a single reporting interval.
+ total_requests_in_progress_.Load(MemoryOrder::RELAXED),
+ GetAndResetCounter(&total_error_requests_),
+ GetAndResetCounter(&total_issued_requests_)};
+ {
+ MutexLock lock(&load_metric_stats_mu_);
+ for (auto& p : load_metric_stats_) {
+ const char* metric_name = p.first.get();
+ LoadMetric& metric_value = p.second;
+ snapshot.load_metric_stats.emplace(
+ UniquePtr<char>(gpr_strdup(metric_name)),
+ metric_value.GetSnapshotAndReset());
+ }
+ }
+ return snapshot;
+}
+
+void XdsClientStats::LocalityStats::AddCallStarted() {
+ total_issued_requests_.FetchAdd(1, MemoryOrder::RELAXED);
+ total_requests_in_progress_.FetchAdd(1, MemoryOrder::RELAXED);
+}
+
+void XdsClientStats::LocalityStats::AddCallFinished(bool fail) {
+ Atomic<uint64_t>& to_increment =
+ fail ? total_error_requests_ : total_successful_requests_;
+ to_increment.FetchAdd(1, MemoryOrder::RELAXED);
+ total_requests_in_progress_.FetchAdd(-1, MemoryOrder::ACQ_REL);
+}
+
+//
+// XdsClientStats::Snapshot
+//
+
+bool XdsClientStats::Snapshot::IsAllZero() {
+ for (auto& p : upstream_locality_stats) {
+ if (!p.second.IsAllZero()) return false;
+ }
+ for (auto& p : dropped_requests) {
+ if (p.second != 0) return false;
+ }
+ return total_dropped_requests == 0;
+}
+
+//
+// XdsClientStats
+//
+
+XdsClientStats::Snapshot XdsClientStats::GetSnapshotAndReset() {
+ grpc_millis now = ExecCtx::Get()->Now();
+ // Record total_dropped_requests and reporting interval in the snapshot.
+ Snapshot snapshot;
+ snapshot.total_dropped_requests =
+ GetAndResetCounter(&total_dropped_requests_);
+ snapshot.load_report_interval = now - last_report_time_;
+ // Update last report time.
+ last_report_time_ = now;
+ // Snapshot all the other stats.
+ for (auto& p : upstream_locality_stats_) {
+ snapshot.upstream_locality_stats.emplace(p.first,
+ p.second->GetSnapshotAndReset());
+ }
+ {
+ MutexLock lock(&dropped_requests_mu_);
+#if GRPC_USE_CPP_STD_LIB
+ // This is a workaround for the case where some compilers cannot build
+ // move-assignment of map with non-copyable but movable key.
+ // https://stackoverflow.com/questions/36475497
+ std::swap(snapshot.dropped_requests, dropped_requests_);
+ dropped_requests_.clear();
+#else
+ snapshot.dropped_requests = std::move(dropped_requests_);
+#endif
+ }
+ return snapshot;
+}
+
+void XdsClientStats::MaybeInitLastReportTime() {
+ if (last_report_time_ == -1) last_report_time_ = ExecCtx::Get()->Now();
+}
+
+RefCountedPtr<XdsClientStats::LocalityStats> XdsClientStats::FindLocalityStats(
+ const RefCountedPtr<XdsLocalityName>& locality_name) {
+ auto iter = upstream_locality_stats_.find(locality_name);
+ if (iter == upstream_locality_stats_.end()) {
+ iter = upstream_locality_stats_
+ .emplace(locality_name, MakeRefCounted<LocalityStats>())
+ .first;
+ }
+ return iter->second;
+}
+
+void XdsClientStats::PruneLocalityStats() {
+ auto iter = upstream_locality_stats_.begin();
+ while (iter != upstream_locality_stats_.end()) {
+ if (iter->second->IsSafeToDelete()) {
+ iter = upstream_locality_stats_.erase(iter);
+ } else {
+ ++iter;
+ }
+ }
+}
+
+void XdsClientStats::AddCallDropped(const UniquePtr<char>& category) {
+ total_dropped_requests_.FetchAdd(1, MemoryOrder::RELAXED);
+ MutexLock lock(&dropped_requests_mu_);
+ auto iter = dropped_requests_.find(category);
+ if (iter == dropped_requests_.end()) {
+ dropped_requests_.emplace(UniquePtr<char>(gpr_strdup(category.get())), 1);
+ } else {
+ ++iter->second;
+ }
+}
+
+} // namespace grpc_core