1 files changed, 140 insertions, 0 deletions
diff --git a/tools/profiler/core/ProfiledThreadData.h b/tools/profiler/core/ProfiledThreadData.h
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+++ b/tools/profiler/core/ProfiledThreadData.h
@@ -0,0 +1,140 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef ProfiledThreadData_h
+#define ProfiledThreadData_h
+
+#include "ThreadInfo.h"
+
+#include "mozilla/Maybe.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/RefPtr.h"
+#include "nsStringFwd.h"
+
+class ProfileBuffer;
+class ProfilerCodeAddressService;
+class UniqueStacks;
+class nsIEventTarget;
+struct JITFrameInfo;
+struct JSContext;
+
+namespace mozilla::baseprofiler {
+class SpliceableJSONWriter;
+}
+
+// This class contains information about a thread that is only relevant while
+// the profiler is running, for any threads (both alive and dead) whose thread
+// name matches the "thread filter" in the current profiler run.
+// ProfiledThreadData objects may be kept alive even after the thread is
+// unregistered, as long as there is still data for that thread in the profiler
+// buffer.
+//
+// Accesses to this class are protected by the profiler state lock.
+//
+// Created as soon as the following are true for the thread:
+//  - The profiler is running, and
+//  - the thread matches the profiler's thread filter, and
+//  - the thread is registered with the profiler.
+// So it gets created in response to either (1) the profiler being started (for
+// an existing registered thread) or (2) the thread being registered (if the
+// profiler is already running).
+//
+// The thread may be unregistered during the lifetime of ProfiledThreadData.
+// If that happens, NotifyUnregistered() is called.
+//
+// This class is the right place to store buffer positions. Profiler buffer
+// positions become invalid if the profiler buffer is destroyed, which happens
+// when the profiler is stopped.
+class ProfiledThreadData final {
+ public:
+  ProfiledThreadData(ThreadInfo* aThreadInfo, nsIEventTarget* aEventTarget);
+  ~ProfiledThreadData();
+
+  void NotifyUnregistered(uint64_t aBufferPosition) {
+    mLastSample = mozilla::Nothing();
+    MOZ_ASSERT(!mBufferPositionWhenReceivedJSContext,
+               "JSContext should have been cleared before the thread was "
+               "unregistered");
+    mUnregisterTime = mozilla::TimeStamp::NowUnfuzzed();
+    mBufferPositionWhenUnregistered = mozilla::Some(aBufferPosition);
+  }
+  mozilla::Maybe<uint64_t> BufferPositionWhenUnregistered() {
+    return mBufferPositionWhenUnregistered;
+  }
+
+  mozilla::Maybe<uint64_t>& LastSample() { return mLastSample; }
+
+  void StreamJSON(const ProfileBuffer& aBuffer, JSContext* aCx,
+                  mozilla::baseprofiler::SpliceableJSONWriter& aWriter,
+                  const nsACString& aProcessName, const nsACString& aETLDplus1,
+                  const mozilla::TimeStamp& aProcessStartTime,
+                  double aSinceTime, bool aJSTracerEnabled,
+                  ProfilerCodeAddressService* aService);
+
+  void StreamTraceLoggerJSON(
+      JSContext* aCx, mozilla::baseprofiler::SpliceableJSONWriter& aWriter,
+      const mozilla::TimeStamp& aProcessStartTime);
+
+  const RefPtr<ThreadInfo> Info() const { return mThreadInfo; }
+
+  void NotifyReceivedJSContext(uint64_t aCurrentBufferPosition) {
+    mBufferPositionWhenReceivedJSContext =
+        mozilla::Some(aCurrentBufferPosition);
+  }
+
+  // Call this method when the JS entries inside the buffer are about to
+  // become invalid, i.e., just before JS shutdown.
+  void NotifyAboutToLoseJSContext(JSContext* aCx,
+                                  const mozilla::TimeStamp& aProcessStartTime,
+                                  ProfileBuffer& aBuffer);
+
+ private:
+  // Group A:
+  // The following fields are interesting for the entire lifetime of a
+  // ProfiledThreadData object.
+
+  // This thread's thread info.
+  const RefPtr<ThreadInfo> mThreadInfo;
+
+  // Contains JSON for JIT frames from any JSContexts that were used for this
+  // thread in the past.
+  // Null if this thread has never lost a JSContext or if all samples from
+  // previous JSContexts have been evicted from the profiler buffer.
+  mozilla::UniquePtr<JITFrameInfo> mJITFrameInfoForPreviousJSContexts;
+
+  // Group B:
+  // The following fields are only used while this thread is alive and
+  // registered. They become Nothing() once the thread is unregistered.
+
+  // When sampling, this holds the position in ActivePS::mBuffer of the most
+  // recent sample for this thread, or Nothing() if there is no sample for this
+  // thread in the buffer.
+  mozilla::Maybe<uint64_t> mLastSample;
+
+  // Only non-Nothing() if the thread currently has a JSContext.
+  mozilla::Maybe<uint64_t> mBufferPositionWhenReceivedJSContext;
+
+  // Group C:
+  // The following fields are only used once this thread has been unregistered.
+
+  mozilla::Maybe<uint64_t> mBufferPositionWhenUnregistered;
+  mozilla::TimeStamp mUnregisterTime;
+};
+
+// Stream all samples and markers from aBuffer with the given aThreadId (or 0
+// for everything, which is assumed to be a single backtrace sample.)
+// Returns the thread id of the output sample(s), or 0 if none was present.
+int StreamSamplesAndMarkers(
+    const char* aName, int aThreadId, const ProfileBuffer& aBuffer,
+    mozilla::baseprofiler::SpliceableJSONWriter& aWriter,
+    const nsACString& aProcessName, const nsACString& aETLDplus1,
+    const mozilla::TimeStamp& aProcessStartTime,
+    const mozilla::TimeStamp& aRegisterTime,
+    const mozilla::TimeStamp& aUnregisterTime, double aSinceTime,
+    UniqueStacks& aUniqueStacks);
+
+#endif  // ProfiledThreadData_h