FFmpeg
timer.h
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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_RISCV
65 # include "riscv/timer.h"
66 #elif ARCH_X86
67 # include "x86/timer.h"
68 #elif ARCH_LOONGARCH
69 # include "loongarch/timer.h"
70 #endif
71 
72 #if !defined(AV_READ_TIME)
73 # if HAVE_GETHRTIME
74 # define AV_READ_TIME gethrtime
75 # elif HAVE_MACH_ABSOLUTE_TIME
76 # define AV_READ_TIME mach_absolute_time
77 # elif HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
78  static inline int64_t ff_read_time(void)
79  {
80  struct timespec ts;
81  clock_gettime(CLOCK_MONOTONIC, &ts);
82  return ts.tv_sec * INT64_C(1000000000) + ts.tv_nsec;
83  }
84 # define AV_READ_TIME ff_read_time
85 # endif
86 #endif
87 
88 #ifndef FF_TIMER_UNITS
89 # define FF_TIMER_UNITS "UNITS"
90 #endif
91 
92 #define TIMER_REPORT(id, tdiff) \
93  { \
94  static uint64_t tsum = 0; \
95  static int tcount = 0; \
96  static int tskip_count = 0; \
97  static int thistogram[32] = {0}; \
98  thistogram[av_log2(tdiff)]++; \
99  if (tcount < 2 || \
100  (tdiff) < 8 * tsum / tcount || \
101  (tdiff) < 2000) { \
102  tsum += (tdiff); \
103  tcount++; \
104  } else \
105  tskip_count++; \
106  if (((tcount + tskip_count) & (tcount + tskip_count - 1)) == 0) { \
107  int i; \
108  av_log(NULL, AV_LOG_ERROR, \
109  "%7" PRIu64 " " FF_TIMER_UNITS " in %s,%8d runs,%7d skips",\
110  tsum * 10 / tcount, id, tcount, tskip_count); \
111  for (i = 0; i < 32; i++) \
112  av_log(NULL, AV_LOG_VERBOSE, " %2d", av_log2(2*thistogram[i]));\
113  av_log(NULL, AV_LOG_ERROR, "\n"); \
114  } \
115  }
116 
117 #if CONFIG_LINUX_PERF
118 
119 #define START_TIMER \
120  static int linux_perf_fd = -1; \
121  uint64_t tperf; \
122  if (linux_perf_fd == -1) { \
123  struct perf_event_attr attr = { \
124  .type = PERF_TYPE_HARDWARE, \
125  .size = sizeof(struct perf_event_attr), \
126  .config = PERF_COUNT_HW_CPU_CYCLES, \
127  .disabled = 1, \
128  .exclude_kernel = 1, \
129  .exclude_hv = 1, \
130  }; \
131  linux_perf_fd = syscall(__NR_perf_event_open, &attr, \
132  0, -1, -1, 0); \
133  } \
134  if (linux_perf_fd == -1) { \
135  av_log(NULL, AV_LOG_ERROR, "perf_event_open failed: %s\n", \
136  av_err2str(AVERROR(errno))); \
137  } else { \
138  ioctl(linux_perf_fd, PERF_EVENT_IOC_RESET, 0); \
139  ioctl(linux_perf_fd, PERF_EVENT_IOC_ENABLE, 0); \
140  }
141 
142 #define STOP_TIMER(id) \
143  ioctl(linux_perf_fd, PERF_EVENT_IOC_DISABLE, 0); \
144  read(linux_perf_fd, &tperf, sizeof(tperf)); \
145  TIMER_REPORT(id, tperf)
146 
147 #elif CONFIG_MACOS_KPERF
148 
149 #define START_TIMER \
150  uint64_t tperf; \
151  ff_kperf_init(); \
152  tperf = ff_kperf_cycles();
153 
154 #define STOP_TIMER(id) \
155  TIMER_REPORT(id, ff_kperf_cycles() - tperf);
156 
157 #elif defined(AV_READ_TIME)
158 #define START_TIMER \
159  uint64_t tend; \
160  uint64_t tstart = AV_READ_TIME(); \
161 
162 #define STOP_TIMER(id) \
163  tend = AV_READ_TIME(); \
164  TIMER_REPORT(id, tend - tstart)
165 #else
166 #define START_TIMER
167 #define STOP_TIMER(id) { }
168 #endif
169 
170 #endif /* AVUTIL_TIMER_H */
timer.h
timer.h
macos_kperf.h
time.h
timer.h
log.h
common.h
timer.h
timer.h
timer.h