Roll Chrome into Mojo.

base/debug/trace_event_synthetic_delay.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// The synthetic delay framework makes it possible to dynamically inject
-// arbitrary delays into into different parts of the codebase. This can be used,
-// for instance, for testing various task scheduling algorithms.
-//
-// The delays are specified in terms of a target duration for a given block of
-// code. If the code executes faster than the duration, the thread is made to
-// sleep until the deadline is met.
-//
-// Code can be instrumented for delays with two sets of macros. First, for
-// delays that should apply within a scope, use the following macro:
-//
-//   TRACE_EVENT_SYNTHETIC_DELAY("cc.LayerTreeHost.DrawAndSwap");
-//
-// For delaying operations that span multiple scopes, use:
-//
-//   TRACE_EVENT_SYNTHETIC_DELAY_BEGIN("cc.Scheduler.BeginMainFrame");
-//   ...
-//   TRACE_EVENT_SYNTHETIC_DELAY_END("cc.Scheduler.BeginMainFrame");
-//
-// Here BEGIN establishes the start time for the delay and END executes the
-// delay based on the remaining time. If BEGIN is called multiple times in a
-// row, END should be called a corresponding number of times. Only the last
-// call to END will have an effect.
-//
-// Note that a single delay may begin on one thread and end on another. This
-// implies that a single delay cannot not be applied in several threads at once.
+// In the process of moving the trace event files. Right now the headers
+// are being forwarded. In next CLs the change will get completed
+// TODO(ssid): https://code.google.com/p/chromium/issues/detail?id=451032
 
 #ifndef BASE_DEBUG_TRACE_EVENT_SYNTHETIC_DELAY_H_
 #define BASE_DEBUG_TRACE_EVENT_SYNTHETIC_DELAY_H_
 
-#include "base/atomicops.h"
-#include "base/debug/trace_event.h"
-#include "base/synchronization/lock.h"
-#include "base/time/time.h"
+#include "base/trace_event/trace_event_synthetic_delay.h"
 
-// Apply a named delay in the current scope.
-#define TRACE_EVENT_SYNTHETIC_DELAY(name)                                     \
-  static base::subtle::AtomicWord INTERNAL_TRACE_EVENT_UID(impl_ptr) = 0;     \
-  trace_event_internal::ScopedSyntheticDelay INTERNAL_TRACE_EVENT_UID(delay)( \
-      name, &INTERNAL_TRACE_EVENT_UID(impl_ptr));
-
-// Begin a named delay, establishing its timing start point. May be called
-// multiple times as long as the calls to TRACE_EVENT_SYNTHETIC_DELAY_END are
-// balanced. Only the first call records the timing start point.
-#define TRACE_EVENT_SYNTHETIC_DELAY_BEGIN(name)                          \
-  do {                                                                   \
-    static base::subtle::AtomicWord impl_ptr = 0;                        \
-    trace_event_internal::GetOrCreateDelay(name, &impl_ptr)->Begin();    \
-  } while (false)
-
-// End a named delay. The delay is applied only if this call matches the
-// first corresponding call to TRACE_EVENT_SYNTHETIC_DELAY_BEGIN with the
-// same delay.
-#define TRACE_EVENT_SYNTHETIC_DELAY_END(name)                         \
-  do {                                                                \
-    static base::subtle::AtomicWord impl_ptr = 0;                     \
-    trace_event_internal::GetOrCreateDelay(name, &impl_ptr)->End();   \
-  } while (false)
-
-template <typename Type>
-struct DefaultSingletonTraits;
-
-namespace base {
-namespace debug {
-
-// Time source for computing delay durations. Used for testing.
-class TRACE_EVENT_API_CLASS_EXPORT TraceEventSyntheticDelayClock {
- public:
-  TraceEventSyntheticDelayClock();
-  virtual ~TraceEventSyntheticDelayClock();
-  virtual base::TimeTicks Now() = 0;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(TraceEventSyntheticDelayClock);
-};
-
-// Single delay point instance.
-class TRACE_EVENT_API_CLASS_EXPORT TraceEventSyntheticDelay {
- public:
-  enum Mode {
-    STATIC,      // Apply the configured delay every time.
-    ONE_SHOT,    // Apply the configured delay just once.
-    ALTERNATING  // Apply the configured delay every other time.
-  };
-
-  // Returns an existing named delay instance or creates a new one with |name|.
-  static TraceEventSyntheticDelay* Lookup(const std::string& name);
-
-  void SetTargetDuration(TimeDelta target_duration);
-  void SetMode(Mode mode);
-  void SetClock(TraceEventSyntheticDelayClock* clock);
-
-  // Begin the delay, establishing its timing start point. May be called
-  // multiple times as long as the calls to End() are balanced. Only the first
-  // call records the timing start point.
-  void Begin();
-
-  // End the delay. The delay is applied only if this call matches the first
-  // corresponding call to Begin() with the same delay.
-  void End();
-
-  // Begin a parallel instance of the delay. Several parallel instances may be
-  // active simultaneously and will complete independently. The computed end
-  // time for the delay is stored in |out_end_time|, which should later be
-  // passed to EndParallel().
-  void BeginParallel(base::TimeTicks* out_end_time);
-
-  // End a previously started parallel delay. |end_time| is the delay end point
-  // computed by BeginParallel().
-  void EndParallel(base::TimeTicks end_time);
-
- private:
-  TraceEventSyntheticDelay();
-  ~TraceEventSyntheticDelay();
-  friend class TraceEventSyntheticDelayRegistry;
-
-  void Initialize(const std::string& name,
-                  TraceEventSyntheticDelayClock* clock);
-  base::TimeTicks CalculateEndTimeLocked(base::TimeTicks start_time);
-  void ApplyDelay(base::TimeTicks end_time);
-
-  Lock lock_;
-  Mode mode_;
-  std::string name_;
-  int begin_count_;
-  int trigger_count_;
-  base::TimeTicks end_time_;
-  base::TimeDelta target_duration_;
-  TraceEventSyntheticDelayClock* clock_;
-
-  DISALLOW_COPY_AND_ASSIGN(TraceEventSyntheticDelay);
-};
-
-// Set the target durations of all registered synthetic delay points to zero.
-TRACE_EVENT_API_CLASS_EXPORT void ResetTraceEventSyntheticDelays();
-
-}  // namespace debug
-}  // namespace base
-
-namespace trace_event_internal {
-
-// Helper class for scoped delays. Do not use directly.
-class TRACE_EVENT_API_CLASS_EXPORT ScopedSyntheticDelay {
- public:
-  explicit ScopedSyntheticDelay(const char* name,
-                                base::subtle::AtomicWord* impl_ptr);
-  ~ScopedSyntheticDelay();
-
- private:
-  base::debug::TraceEventSyntheticDelay* delay_impl_;
-  base::TimeTicks end_time_;
-
-  DISALLOW_COPY_AND_ASSIGN(ScopedSyntheticDelay);
-};
-
-// Helper for registering delays. Do not use directly.
-TRACE_EVENT_API_CLASS_EXPORT base::debug::TraceEventSyntheticDelay*
-    GetOrCreateDelay(const char* name, base::subtle::AtomicWord* impl_ptr);
-
-}  // namespace trace_event_internal
-
-#endif /* BASE_DEBUG_TRACE_EVENT_SYNTHETIC_DELAY_H_ */
+#endif  // BASE_DEBUG_TRACE_EVENT_SYNTHETIC_DELAY_H_