CPU affinity feature work with trace aggregator

cactusdynamics · Jul 30, 2023 · f9a4a17 · f9a4a17
1 parent 2e45028
commit f9a4a17
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Showing 3 changed files with 42 additions and 6 deletions.
diff --git a/examples/tracing_example/main.cc b/examples/tracing_example/main.cc
@@ -58,13 +58,16 @@ int main() {
  cactus_rt::FifoThreadConfig fifo_config;
  fifo_config.priority = 80;
 
- cactus_rt::CyclicThreadConfig config;
- config.name = "ExampleRTThread";
- config.period_ns = 1'000'000;
- config.scheduler_config = fifo_config;
+ cactus_rt::CyclicThreadConfig thread_config;
+ thread_config.name = "ExampleRTThread";
+ thread_config.period_ns = 1'000'000;
+ thread_config.scheduler_config = fifo_config;
 
- auto thread = std::make_shared<ExampleRTThread>(config);
- App app;
+ cactus_rt::AppConfig app_config;
+ app_config.tracer_config.trace_aggregator_cpu_affinity = {1};
+
+ auto thread = std::make_shared<ExampleRTThread>(thread_config);
+ App app(app_config);
  app.RegisterThread(thread);
 
  std::cout << "Testing RT loop for 15 seconds with two trace sessions.\n";

diff --git a/include/cactus_rt/tracing/trace_aggregator.h b/include/cactus_rt/tracing/trace_aggregator.h
@@ -98,6 +98,8 @@ class TraceAggregator {
  void Run();
  bool StopRequested() const noexcept;
 
+ void SetupCPUAffinityIfNecessary() const;
+
  Trace CreateProcessDescriptorPacket() const;
  Trace CreateThreadDescriptorPacket(const ThreadTracer& thread_tracer) const;
  void AddTrackEventPacketToTrace(Trace& trace, const ThreadTracer& thread_tracer, const TrackEventInternal& track_event_internal) const;

diff --git a/src/cactus_rt/tracing/trace_aggregator.cc b/src/cactus_rt/tracing/trace_aggregator.cc
@@ -1,6 +1,15 @@
 #include "cactus_rt/tracing/trace_aggregator.h"
 
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <pthread.h>
+#include <sched.h>
+
 #include <chrono>
+#include <cstring>
+#include <string>
 
 using Trace = cactus_tracing::vendor::perfetto::protos::Trace;
 using TrackDescriptor = cactus_tracing::vendor::perfetto::protos::TrackDescriptor;
@@ -89,6 +98,8 @@ quill::Logger* TraceAggregator::Logger() noexcept {
 }
 
 void TraceAggregator::Run() {
+ SetupCPUAffinityIfNecessary();
+
  // TODO: major refactor required
 
  while (!StopRequested()) {
@@ -171,6 +182,26 @@ bool TraceAggregator::StopRequested() const noexcept {
  return stop_requested_.load(std::memory_order_relaxed);
 }
 
+void TraceAggregator::SetupCPUAffinityIfNecessary() const {
+ if (cpu_affinity_.empty()) {
+ return;
+ }
+
+ cpu_set_t cpuset;
+ CPU_ZERO(&cpuset);
+ for (auto cpu : cpu_affinity_) {
+ CPU_SET(cpu, &cpuset);
+ }
+
+ pthread_t current_thread = pthread_self();
+ int ret = pthread_setaffinity_np(current_thread, sizeof(cpu_set_t), &cpuset);
+ if (ret == 0) {
+ return;
+ }
+
+ throw std::runtime_error{std::string("cannot set affinity for trace aggregator: ") + std::strerror(errno)};
+}
+
 Trace TraceAggregator::CreateProcessDescriptorPacket() const {
  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks)
  Trace trace;