Kernel+LibC: Add PERF_EVENT_SIGNPOST

This event will be used by userspace programs wanting to mark interesting high-level events in the profile. :^)
Cnidarias · Aug 11, 2021 · 0d997d4 · 0d997d4
1 parent 8405381
commit 0d997d4
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Showing 4 changed files with 17 additions and 0 deletions.
diff --git a/Kernel/PerformanceEventBuffer.cpp b/Kernel/PerformanceEventBuffer.cpp
@@ -137,6 +137,10 @@ KResult PerformanceEventBuffer::append_with_ip_and_bp(ProcessID pid, ThreadID ti
  break;
  case PERF_EVENT_SYSCALL:
  break;
+ case PERF_EVENT_SIGNPOST:
+ event.data.signpost.arg1 = arg1;
+ event.data.signpost.arg2 = arg2;
+ break;
  default:
  return EINVAL;
  }
@@ -231,6 +235,11 @@ bool PerformanceEventBuffer::to_json_impl(Serializer& object) const
  case PERF_EVENT_SYSCALL:
  event_object.add("type", "syscall");
  break;
+ case PERF_EVENT_SIGNPOST:
+ event_object.add("type"sv, "signpost"sv);
+ event_object.add("arg1"sv, event.data.signpost.arg1);
+ event_object.add("arg2"sv, event.data.signpost.arg2);
+ break;
  }
  event_object.add("pid", event.pid);
  event_object.add("tid", event.tid);

diff --git a/Kernel/PerformanceEventBuffer.h b/Kernel/PerformanceEventBuffer.h
@@ -62,6 +62,11 @@ struct [[gnu::packed]] KFreePerformanceEvent {
  FlatPtr ptr;
 };
 
+struct [[gnu::packed]] SignpostPerformanceEvent {
+ FlatPtr arg1;
+ FlatPtr arg2;
+};
+
 struct [[gnu::packed]] PerformanceEvent {
  u16 type { 0 };
  u8 stack_size { 0 };
@@ -80,6 +85,7 @@ struct [[gnu::packed]] PerformanceEvent {
  ContextSwitchPerformanceEvent context_switch;
  KMallocPerformanceEvent kmalloc;
  KFreePerformanceEvent kfree;
+ SignpostPerformanceEvent signpost;
  } data;
  static constexpr size_t max_stack_frame_count = 64;
  FlatPtr stack[max_stack_frame_count];

diff --git a/Kernel/UnixTypes.h b/Kernel/UnixTypes.h
@@ -63,6 +63,7 @@ enum {
  PERF_EVENT_KFREE = 4096,
  PERF_EVENT_PAGE_FAULT = 8192,
  PERF_EVENT_SYSCALL = 16384,
+ PERF_EVENT_SIGNPOST = 32768,
 };
 
 #define WNOHANG 1

diff --git a/Userland/Libraries/LibC/serenity.h b/Userland/Libraries/LibC/serenity.h
@@ -113,6 +113,7 @@ enum {
  PERF_EVENT_KFREE = 4096,
  PERF_EVENT_PAGE_FAULT = 8192,
  PERF_EVENT_SYSCALL = 16384,
+ PERF_EVENT_SIGNPOST = 32768,
 };
 
 #define PERF_EVENT_MASK_ALL (~0ull)