1 /* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
4
5 #include "nsStopwatch.h"
6
7 #include <stdio.h>
8 #include <time.h>
9 #if defined(XP_UNIX)
10 # include <unistd.h>
11 # include <sys/times.h>
12 # include <sys/time.h>
13 # include <errno.h>
14 #elif defined(XP_WIN)
15 # include "windows.h"
16 #endif // elif defined(XP_WIN)
17
18 #include "nsMemory.h"
19 /*
20 * This basis for the logic in this file comes from (will used to come from):
21 * (mozilla/)modules/libutil/public/stopwatch.cpp.
22 *
23 * It was no longer used in the mozilla tree, and is being migrated to
24 * comm-central where we actually have a need for it. ("Being" in the sense
25 * that it will not be removed immediately from mozilla-central.)
26 *
27 * Simplification and general clean-up has been performed and the fix for
28 * bug 96669 has been integrated.
29 */
30
31 NS_IMPL_ISUPPORTS(nsStopwatch, nsIStopwatch)
32
33 #if defined(XP_UNIX)
34 /** the number of ticks per second */
35 static double gTicks = 0;
36 # define MICRO_SECONDS_TO_SECONDS_MULT static_cast<double>(1.0e-6)
37 #elif defined(WIN32)
38 # ifdef DEBUG
39 # include "nsPrintfCString.h"
40 # endif
41 // 1 tick per 100ns = 10 per us = 10 * 1,000 per ms = 10 * 1,000 * 1,000 per
42 // sec.
43 # define WIN32_TICK_RESOLUTION static_cast<double>(1.0e-7)
44 // subtract off to get to the unix epoch
45 # define UNIX_EPOCH_IN_FILE_TIME 116444736000000000L
46 #endif // elif defined(WIN32)
47
nsStopwatch()48 nsStopwatch::nsStopwatch()
49 : fTotalRealTimeSecs(0.0), fTotalCpuTimeSecs(0.0), fRunning(false) {
50 #if defined(XP_UNIX)
51 // idempotent in the event of a race under all coherency models
52 if (!gTicks) {
53 // we need to clear errno because sysconf's spec says it leaves it the same
54 // on success and only sets it on failure.
55 errno = 0;
56 gTicks = (clock_t)sysconf(_SC_CLK_TCK);
57 // in event of failure, pick an arbitrary value so we don't divide by zero.
58 if (errno) gTicks = 1000000L;
59 }
60 #endif
61 }
62
~nsStopwatch()63 nsStopwatch::~nsStopwatch() {}
64
Start()65 NS_IMETHODIMP nsStopwatch::Start() {
66 fTotalRealTimeSecs = 0.0;
67 fTotalCpuTimeSecs = 0.0;
68 return Resume();
69 }
70
Stop()71 NS_IMETHODIMP nsStopwatch::Stop() {
72 fStopRealTimeSecs = GetRealTime();
73 fStopCpuTimeSecs = GetCPUTime();
74 if (fRunning) {
75 fTotalCpuTimeSecs += fStopCpuTimeSecs - fStartCpuTimeSecs;
76 fTotalRealTimeSecs += fStopRealTimeSecs - fStartRealTimeSecs;
77 }
78 fRunning = false;
79 return NS_OK;
80 }
81
Resume()82 NS_IMETHODIMP nsStopwatch::Resume() {
83 if (!fRunning) {
84 fStartRealTimeSecs = GetRealTime();
85 fStartCpuTimeSecs = GetCPUTime();
86 }
87 fRunning = true;
88 return NS_OK;
89 }
90
GetCpuTimeSeconds(double * result)91 NS_IMETHODIMP nsStopwatch::GetCpuTimeSeconds(double* result) {
92 NS_ENSURE_ARG_POINTER(result);
93 *result = fTotalCpuTimeSecs;
94 return NS_OK;
95 }
96
GetRealTimeSeconds(double * result)97 NS_IMETHODIMP nsStopwatch::GetRealTimeSeconds(double* result) {
98 NS_ENSURE_ARG_POINTER(result);
99 *result = fTotalRealTimeSecs;
100 return NS_OK;
101 }
102
GetRealTime()103 double nsStopwatch::GetRealTime() {
104 #if defined(XP_UNIX)
105 struct timeval t;
106 gettimeofday(&t, NULL);
107 return t.tv_sec + t.tv_usec * MICRO_SECONDS_TO_SECONDS_MULT;
108 #elif defined(WIN32)
109 union {
110 FILETIME ftFileTime;
111 __int64 ftInt64;
112 } ftRealTime; // time the process has spent in kernel mode
113 SYSTEMTIME st;
114 GetSystemTime(&st);
115 SystemTimeToFileTime(&st, &ftRealTime.ftFileTime);
116 return (ftRealTime.ftInt64 - UNIX_EPOCH_IN_FILE_TIME) * WIN32_TICK_RESOLUTION;
117 #else
118 # error "nsStopwatch not supported on this platform."
119 #endif
120 }
121
GetCPUTime()122 double nsStopwatch::GetCPUTime() {
123 #if defined(XP_UNIX)
124 struct tms cpt;
125 times(&cpt);
126 return (double)(cpt.tms_utime + cpt.tms_stime) / gTicks;
127 #elif defined(WIN32)
128 FILETIME ftCreate, // when the process was created
129 ftExit; // when the process exited
130
131 union {
132 FILETIME ftFileTime;
133 __int64 ftInt64;
134 } ftKernel; // time the process has spent in kernel mode
135
136 union {
137 FILETIME ftFileTime;
138 __int64 ftInt64;
139 } ftUser; // time the process has spent in user mode
140
141 HANDLE hProcess = GetCurrentProcess();
142 # ifdef DEBUG
143 BOOL ret =
144 # endif
145 GetProcessTimes(hProcess, &ftCreate, &ftExit, &ftKernel.ftFileTime,
146 &ftUser.ftFileTime);
147 # ifdef DEBUG
148 if (!ret)
149 NS_ERROR(nsPrintfCString("GetProcessTimes() failed, error=0x%lx.",
150 GetLastError())
151 .get());
152 # endif
153
154 /*
155 * Process times are returned in a 64-bit structure, as the number of
156 * 100 nanosecond ticks since 1 January 1601. User mode and kernel mode
157 * times for this process are in separate 64-bit structures.
158 * Add them and convert the result to seconds.
159 */
160 return (ftKernel.ftInt64 + ftUser.ftInt64) * WIN32_TICK_RESOLUTION;
161 #else
162 # error "nsStopwatch not supported on this platform."
163 #endif
164 }
165