FFmpeg
timer.h
Go to the documentation of this file.
1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * high precision timer, useful to profile code
24  */
25 
26 #ifndef AVUTIL_TIMER_H
27 #define AVUTIL_TIMER_H
28 
29 #include "config.h"
30 
31 #if CONFIG_LINUX_PERF
32 # ifndef _GNU_SOURCE
33 # define _GNU_SOURCE
34 # endif
35 # include <unistd.h> // read(3)
36 # include <sys/ioctl.h>
37 # include <asm/unistd.h>
38 # include <linux/perf_event.h>
39 #endif
40 
41 #include <stdlib.h>
42 #include <stdint.h>
43 #include <inttypes.h>
44 
45 #if CONFIG_MACOS_KPERF
46 #include "macos_kperf.h"
47 #endif
48 
49 #if HAVE_MACH_ABSOLUTE_TIME
50 #include <mach/mach_time.h>
51 #elif HAVE_CLOCK_GETTIME
52 #include <time.h>
53 #endif
54 
55 #include "common.h"
56 #include "log.h"
57 
58 #if ARCH_AARCH64
59 # include "aarch64/timer.h"
60 #elif ARCH_ARM
61 # include "arm/timer.h"
62 #elif ARCH_PPC
63 # include "ppc/timer.h"
64 #elif ARCH_X86
65 # include "x86/timer.h"
66 #elif ARCH_LOONGARCH
67 # include "loongarch/timer.h"
68 #endif
69 
70 #if !defined(AV_READ_TIME)
71 # if HAVE_GETHRTIME
72 # define AV_READ_TIME gethrtime
73 # elif HAVE_MACH_ABSOLUTE_TIME
74 # define AV_READ_TIME mach_absolute_time
75 # elif HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
76  static inline int64_t ff_read_time(void)
77  {
78  struct timespec ts;
79  clock_gettime(CLOCK_MONOTONIC, &ts);
80  return ts.tv_sec * INT64_C(1000000000) + ts.tv_nsec;
81  }
82 # define AV_READ_TIME ff_read_time
83 # define FF_TIMER_UNITS "ns"
84 # endif
85 #endif
86 
87 #ifndef FF_TIMER_UNITS
88 # define FF_TIMER_UNITS "UNITS"
89 #endif
90 
91 #define TIMER_REPORT(id, tdiff) \
92  { \
93  static uint64_t tsum = 0; \
94  static int tcount = 0; \
95  static int tskip_count = 0; \
96  static int thistogram[32] = {0}; \
97  thistogram[av_log2(tdiff)]++; \
98  if (tcount < 2 || \
99  (tdiff) < 8 * tsum / tcount || \
100  (tdiff) < 2000) { \
101  tsum += (tdiff); \
102  tcount++; \
103  } else \
104  tskip_count++; \
105  if (((tcount + tskip_count) & (tcount + tskip_count - 1)) == 0) { \
106  int i; \
107  av_log(NULL, AV_LOG_ERROR, \
108  "%7" PRIu64 " " FF_TIMER_UNITS " in %s,%8d runs,%7d skips",\
109  tsum * 10 / tcount, id, tcount, tskip_count); \
110  for (i = 0; i < 32; i++) \
111  av_log(NULL, AV_LOG_VERBOSE, " %2d", av_log2(2*thistogram[i]));\
112  av_log(NULL, AV_LOG_ERROR, "\n"); \
113  } \
114  }
115 
116 #if CONFIG_LINUX_PERF
117 
118 #define START_TIMER \
119  static int linux_perf_fd = -1; \
120  uint64_t tperf; \
121  if (linux_perf_fd == -1) { \
122  struct perf_event_attr attr = { \
123  .type = PERF_TYPE_HARDWARE, \
124  .size = sizeof(struct perf_event_attr), \
125  .config = PERF_COUNT_HW_CPU_CYCLES, \
126  .disabled = 1, \
127  .exclude_kernel = 1, \
128  .exclude_hv = 1, \
129  }; \
130  linux_perf_fd = syscall(__NR_perf_event_open, &attr, \
131  0, -1, -1, 0); \
132  } \
133  if (linux_perf_fd == -1) { \
134  av_log(NULL, AV_LOG_ERROR, "perf_event_open failed: %s\n", \
135  av_err2str(AVERROR(errno))); \
136  } else { \
137  ioctl(linux_perf_fd, PERF_EVENT_IOC_RESET, 0); \
138  ioctl(linux_perf_fd, PERF_EVENT_IOC_ENABLE, 0); \
139  }
140 
141 #define STOP_TIMER(id) \
142  ioctl(linux_perf_fd, PERF_EVENT_IOC_DISABLE, 0); \
143  read(linux_perf_fd, &tperf, sizeof(tperf)); \
144  TIMER_REPORT(id, tperf)
145 
146 #elif CONFIG_MACOS_KPERF
147 
148 #define START_TIMER \
149  uint64_t tperf; \
150  ff_kperf_init(); \
151  tperf = ff_kperf_cycles();
152 
153 #define STOP_TIMER(id) \
154  TIMER_REPORT(id, ff_kperf_cycles() - tperf);
155 
156 #elif defined(AV_READ_TIME)
157 #define START_TIMER \
158  uint64_t tend; \
159  uint64_t tstart = AV_READ_TIME(); \
160 
161 #define STOP_TIMER(id) \
162  tend = AV_READ_TIME(); \
163  TIMER_REPORT(id, tend - tstart)
164 #else
165 #define START_TIMER
166 #define STOP_TIMER(id) { }
167 #endif
168 
169 #endif /* AVUTIL_TIMER_H */
int64_t
long long int64_t
Definition: coverity.c:34
timer.h
timer.h
macos_kperf.h
time.h
timer.h
log.h
common.h
timer.h
timer.h
Generated on Thu Dec 26 2024 19:23:01 for FFmpeg by   doxygen 1.8.17