Special-case Timeline.{start,finish}Sync for Fuchsia

runtime/vm/timeline_fuchsia.cc

Index: runtime/vm/timeline_fuchsia.cc
diff --git a/runtime/vm/timeline_fuchsia.cc b/runtime/vm/timeline_fuchsia.cc
new file mode 100644
index 0000000000000000000000000000000000000000..23ce85f79a27ba43b6becd07dfdbce83de239477
--- /dev/null
+++ b/runtime/vm/timeline_fuchsia.cc
@@ -0,0 +1,207 @@
+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+#include "platform/globals.h"
+#if defined(HOST_OS_FUCHSIA) && !defined(PRODUCT)
+
+#include "apps/tracing/lib/trace/cwriter.h"
+#include "apps/tracing/lib/trace/event.h"
+#include "vm/object.h"
+#include "vm/timeline.h"
+
+namespace dart {
+
+// A recorder that sends events to Fuchsia's tracing app. Events are also stored
+// in a buffer of fixed capacity. When the buffer is full, new events overwrite
+// old events.
+// See: https://fuchsia.googlesource.com/tracing/+/HEAD/docs/usage_guide.md
+
+TimelineEventPlatformRecorder::TimelineEventPlatformRecorder(intptr_t capacity)
+    : TimelineEventFixedBufferRecorder(capacity) {}
+
+TimelineEventPlatformRecorder::~TimelineEventPlatformRecorder() {}
+
+TimelineEventPlatformRecorder*
+TimelineEventPlatformRecorder::CreatePlatformRecorder(intptr_t capacity) {
+  return new TimelineEventPlatformRecorder(capacity);
+}
+
+const char* TimelineEventPlatformRecorder::name() const {
+  return "Fuchsia";
+}
+
+TimelineEventBlock* TimelineEventPlatformRecorder::GetNewBlockLocked() {
+  // TODO(johnmccutchan): This function should only hand out blocks
+  // which have been marked as finished.
+  if (block_cursor_ == num_blocks_) {
+    block_cursor_ = 0;
+  }
+  TimelineEventBlock* block = blocks_[block_cursor_++];
+  block->Reset();
+  block->Open();
+  return block;
+}
+
+void TimelineEventPlatformRecorder::CompleteEvent(TimelineEvent* event) {
+  if (event == NULL) {
+    return;
+  }
+  if (!ctrace_is_enabled()) {
+    ThreadBlockCompleteEvent(event);
+    return;
+  }
+  auto writer = ctrace_writer_acquire();
+
+  // XXX: use ctrace_register_category_string();
+  ctrace_stringref_t category;
+  ctrace_register_string(writer, "dart", &category);
+
+  ctrace_stringref_t name;
+  ctrace_register_string(writer, event->label(), &name);
+
+  ctrace_threadref_t thread;
+  ctrace_register_current_thread(writer, &thread);
+
+  ctrace_argspec_t args[2];
+  ctrace_arglist_t arglist = {0, args};
+
+  if (event->arguments_length() >= 1) {
+    args[0].type = CTRACE_ARGUMENT_STRING;
+    args[0].name = event->arguments()[0].name;
+    args[0].u.s = event->arguments()[0].value;
+    arglist.n_args += 1;
+  }
+  if (event->arguments_length() >= 2) {
+    args[1].type = CTRACE_ARGUMENT_STRING;
+    args[1].name = event->arguments()[1].name;
+    args[1].u.s = event->arguments()[1].value;
+    arglist.n_args += 1;
+  }
+
+  const uint64_t time_scale = mx_ticks_per_second() / kMicrosecondsPerSecond;
+  const uint64_t start_time = event->LowTime() * time_scale;
+  const uint64_t end_time = event->HighTime() * time_scale;
+
+  // TODO(zra): The functions below emit Dart's timeline events all as category
+  // "dart". Instead, we could have finer-grained categories that make use of
+  // the name of the timeline stream, e.g. "VM", "GC", etc.
+  switch (event->event_type()) {
+    case TimelineEvent::kBegin:
+      ctrace_write_duration_begin_event_record(writer, start_time, &thread,
+                                               &category, &name, &arglist);
+      break;
+    case TimelineEvent::kEnd:
+      ctrace_write_duration_end_event_record(writer, end_time, &thread,
+                                             &category, &name, &arglist);
+      break;
+    case TimelineEvent::kInstant:
+      ctrace_write_instant_event_record(writer, start_time, &thread, &category,
+                                        &name, CTRACE_SCOPE_THREAD, &arglist);
+      break;
+    case TimelineEvent::kAsyncBegin:
+      ctrace_write_async_begin_event_record(writer, start_time, &thread,
+                                            &category, &name, event->AsyncId(),
+                                            &arglist);
+      break;
+    case TimelineEvent::kAsyncEnd:
+      ctrace_write_async_end_event_record(writer, end_time, &thread, &category,
+                                          &name, event->AsyncId(), &arglist);
+      break;
+    case TimelineEvent::kAsyncInstant:
+      ctrace_write_async_instant_event_record(writer, start_time, &thread,
+                                              &category, &name,
+                                              event->AsyncId(), &arglist);
+      break;
+    case TimelineEvent::kDuration:
+      ctrace_write_duration_event_record(writer, start_time, end_time, &thread,
+                                         &category, &name, &arglist);
+      break;
+    case TimelineEvent::kFlowBegin:
+      ctrace_write_flow_begin_event_record(writer, start_time, &thread,
+                                           &category, &name, event->AsyncId(),
+                                           &arglist);
+      break;
+    case TimelineEvent::kFlowStep:
+      ctrace_write_flow_step_event_record(writer, start_time, &thread,
+                                          &category, &name, event->AsyncId(),
+                                          &arglist);
+      break;
+    case TimelineEvent::kFlowEnd:
+      ctrace_write_flow_end_event_record(writer, start_time, &thread, &category,
+                                         &name, event->AsyncId(), &arglist);
+      break;
+    default:
+      // TODO(zra): Figure out what to do with kCounter and kMetadata.
+      break;
+  }
+  ctrace_writer_release(writer);
+  ThreadBlockCompleteEvent(event);
+}
+
+void DartTimelineEventHelpers::ReportTaskEvent(Thread* thread,
+                                               Zone* zone,
+                                               TimelineEvent* event,
+                                               int64_t start,
+                                               int64_t id,
+                                               const char* phase,
+                                               const char* category,
+                                               const char* name,
+                                               const char* args) {
+  char* name_string = strdup(name);
+  ASSERT(phase != NULL);
+  ASSERT((phase[0] == 'n') || (phase[0] == 'b') || (phase[0] == 'e'));
+  ASSERT(phase[1] == '\0');
+  switch (phase[0]) {
+    case 'n':
+      event->AsyncInstant(name_string, id, start);
+      break;
+    case 'b':
+      event->AsyncBegin(name_string, id, start);
+      break;
+    case 'e':
+      event->AsyncEnd(name_string, id, start);
+      break;
+    default:
+      UNREACHABLE();
+  }
+  event->set_owns_label(true);
+  event->SetNumArguments(1);
+  event->CopyArgument(0, "args", args);
+  event->Complete();
+}
+
+void DartTimelineEventHelpers::ReportCompleteEvent(Thread* thread,
+                                                   Zone* zone,
+                                                   TimelineEvent* event,
+                                                   int64_t start,
+                                                   int64_t start_cpu,
+                                                   const char* category,
+                                                   const char* name,
+                                                   const char* args) {
+  const int64_t end = OS::GetCurrentMonotonicMicros();
+  const int64_t end_cpu = OS::GetCurrentThreadCPUMicros();
+  event->Duration(strdup(name), start, end, start_cpu, end_cpu);
+  event->set_owns_label(true);
+  event->SetNumArguments(1);
+  event->CopyArgument(0, "args", args);
+  event->Complete();
+}
+
+void DartTimelineEventHelpers::ReportInstantEvent(Thread* thread,
+                                                  Zone* zone,
+                                                  TimelineEvent* event,
+                                                  int64_t start,
+                                                  const char* category,
+                                                  const char* name,
+                                                  const char* args) {
+  event->Instant(strdup(name), start);
+  event->set_owns_label(true);
+  event->SetNumArguments(1);
+  event->CopyArgument(0, "args", args);
+  event->Complete();
+}
+
+}  // namespace dart
+
+#endif  // defined(HOST_OS_FUCHSIA) && !defined(PRODUCT)