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Issue 624713003: Keep only base/extractor.[cc|h]. (Closed) Base URL: https://chromium.googlesource.com/external/omaha.git@master
Patch Set: Created 6 years, 2 months ago
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1 // Copyright 2003-2009 Google Inc.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 // ========================================================================
15 //
16 // Timing
17
18 #ifndef OMAHA_BASE_TIMER_H_
19 #define OMAHA_BASE_TIMER_H_
20
21 #include "omaha/base/time.h"
22
23 namespace omaha {
24
25 // Low resolution timer which can be used to time loops. The resolution depends
26 // on the platform and can be expected to be about 10 ms on Windows 2000 and up.
27 class LowResTimer {
28 public:
29 explicit LowResTimer(bool running);
30 ~LowResTimer();
31
32 // LowResTimer keeps track of elapsed time, which can consist of multiple
33 // Start()-Stop() intervals.
34 void Start();
35
36 // Returns time between Start and Stop call and increments the time elapsed.
37 uint32 Stop();
38 void Reset();
39
40 // Return time in seconds, milliseconds.
41 double GetSeconds() const;
42 uint32 GetMilliseconds() const;
43
44 // Gets the number of iteration this timer was started/stopped.
45 uint32 GetIterations() const { return iterations_; }
46 bool IsRunning() const { return running_; }
47
48 private:
49
50 bool running_;
51 uint32 start_;
52 uint32 elapsed_;
53 uint32 iterations_;
54
55 DISALLOW_EVIL_CONSTRUCTORS(LowResTimer);
56 };
57
58 inline double LowResTimer::GetSeconds() const {
59 return static_cast<double>(GetMilliseconds()) / 1000;
60 }
61
62 // WARNING - Timer is implemented on top of RDTSC and
63 // QueryPerformanceCounter which have undefined behavior when running
64 // on multi-core, speedstep, bugs in HAL, certain chipsets, etc.
65 // Do not use the Timer in production code where the execution flow
66 // depends on timing. Timer is primarily intended to be used for
67 // code profiling and performance measurements.
68 class Timer {
69 public:
70 explicit Timer(bool running);
71 ~Timer();
72
73 // Timer keeps track of elapsed time, which can consist of multiple
74 // Start()-Stop() intervals.
75 void Start();
76
77 // returns time for last split (elapsed time since Start() or time since
78 // last Split(), whichever came last) as well as total elapsed time.
79 void Split(double* split_time_ms, double* total_time_ms);
80
81 // returns time elapsed (in hi-res perf-counts) between Start and Stop call
82 // and increments the time elapsed_
83 time64 Stop();
84 void Reset();
85
86 // return time in seconds, milliseconds, etc.
87 double GetSeconds() const;
88 double GetMilliseconds() const;
89 double GetMicroseconds() const;
90 double GetNanoseconds() const;
91 time64 Get100Nanoseconds() const;
92
93 // TODO(omaha): Probably should have been a static method, or even
94 // standalone func convert the high-perf counter to nano-seconds
95 double PerfCountToNanoSeconds(time64 perf_count) const;
96
97 // get the number of iteration this timer was started/stopped
98 uint32 GetIterations() const { return iterations_; }
99 bool IsRunning() const { return running_; }
100
101 // useful funcs beyond just the Timer class
102 static time64 GetRdtscCounter(); // return perf-counter value
103 static time64 GetRdtscFrequency(); // return perf-counter frequency
104
105 // outputs total time, number of iterations, and the average time
106 #ifdef _DEBUG
107 CString DebugString() const;
108 #endif
109
110 private:
111
112 bool running_;
113 time64 start_;
114 time64 split_;
115 time64 elapsed_;
116 uint32 iterations_;
117 static time64 count_freq_;
118
119 DISALLOW_EVIL_CONSTRUCTORS(Timer);
120 };
121
122 // lint -e{533} Function should return a value
123 // lint -e{31} Redefinition of symbol
124 __forceinline time64 Timer::GetRdtscCounter() { __asm rdtsc }
125
126 inline double Timer::PerfCountToNanoSeconds(time64 perf_count) const {
127 return (static_cast<double>(perf_count) / static_cast<double>(count_freq_)) *
128 static_cast<double>(1000000000.0);
129 }
130
131 inline double Timer::GetSeconds() const {
132 return GetNanoseconds() / 1000000000;
133 }
134
135 inline double Timer::GetMilliseconds() const {
136 return GetNanoseconds() / 1000000;
137 }
138
139 inline double Timer::GetMicroseconds() const {
140 return GetNanoseconds() / 1000;
141 }
142
143 inline time64 Timer::Get100Nanoseconds() const {
144 return (time64) GetNanoseconds() / 100;
145 }
146
147 // Helper class which starts the timer in its constructor and stops it
148 // in its destructor. This prevents accidentally leaving the timer running
149 // if a function has an early exit.
150 //
151 // Usage:
152 //
153 // class A {
154 // Timer timer_;
155 //
156 // void foo(){
157 // TimerScope (timer_);
158 // ......
159 // } // end foo
160 //
161 // Everything is timed till the end of the function or when it returns
162 // from any place.
163
164 class TimerScope {
165 public:
166 explicit TimerScope(Timer *timer) : timer_(timer) {
167 if (timer_) {
168 timer_->Start();
169 }
170 }
171
172 ~TimerScope() {
173 if (timer_ && timer_->IsRunning()) {
174 timer_->Stop();
175 }
176 }
177
178 private:
179 Timer *timer_;
180 DISALLOW_EVIL_CONSTRUCTORS(TimerScope);
181 };
182
183 } // namespace omaha
184
185 #endif // OMAHA_BASE_TIMER_H_
186
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