rocksdb/monitoring/perf_context_imp.h

//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
//  This source code is licensed under both the GPLv2 (found in the
//  COPYING file in the root directory) and Apache 2.0 License
//  (found in the LICENSE.Apache file in the root directory).
//
#pragma once
#include "monitoring/perf_step_timer.h"
#include "rocksdb/perf_context.h"
#include "util/stop_watch.h"

namespace rocksdb {

#if defined(NPERF_CONTEXT)

#define PERF_TIMER_GUARD(metric)
#define PERF_CONDITIONAL_TIMER_FOR_MUTEX_GUARD(metric, condition)
#define PERF_TIMER_MEASURE(metric)
#define PERF_TIMER_STOP(metric)
#define PERF_TIMER_START(metric)
#define PERF_COUNTER_ADD(metric, value)

#else

// Stop the timer and update the metric
#define PERF_TIMER_STOP(metric) perf_step_timer_##metric.Stop();

#define PERF_TIMER_START(metric) perf_step_timer_##metric.Start();

// Declare and set start time of the timer
#define PERF_TIMER_GUARD(metric)                                       \
  PerfStepTimer perf_step_timer_##metric(&(get_perf_context()->metric)); \
  perf_step_timer_##metric.Start();

#define PERF_CONDITIONAL_TIMER_FOR_MUTEX_GUARD(metric, condition)            \
  PerfStepTimer perf_step_timer_##metric(&(get_perf_context()->metric), true); \
  if ((condition)) {                                                         \
    perf_step_timer_##metric.Start();                                        \
  }

// Update metric with time elapsed since last START. start time is reset
// to current timestamp.
#define PERF_TIMER_MEASURE(metric) perf_step_timer_##metric.Measure();

// Increase metric value
#define PERF_COUNTER_ADD(metric, value)        \
  if (perf_level >= PerfLevel::kEnableCount) { \
    get_perf_context()->metric += value;       \
  }

#endif

}