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 #elif HAVE_MACH_ABSOLUTE_TIME
48 #include <mach/mach_time.h>
49 #endif
50 
51 #include "common.h"
52 #include "log.h"
53 
54 #if   ARCH_AARCH64
55 #   include "aarch64/timer.h"
56 #elif ARCH_ARM
57 #   include "arm/timer.h"
58 #elif ARCH_PPC
59 #   include "ppc/timer.h"
60 #elif ARCH_X86
61 #   include "x86/timer.h"
62 #endif
63 
64 #if !defined(AV_READ_TIME)
65 #   if HAVE_GETHRTIME
66 #       define AV_READ_TIME gethrtime
67 #   elif HAVE_MACH_ABSOLUTE_TIME
68 #       define AV_READ_TIME mach_absolute_time
69 #   endif
70 #endif
71 
72 #ifndef FF_TIMER_UNITS
73 #   define FF_TIMER_UNITS "UNITS"
74 #endif
75 
76 #define TIMER_REPORT(id, tdiff)                                           \
77     {                                                                     \
78         static uint64_t tsum   = 0;                                       \
79         static int tcount      = 0;                                       \
80         static int tskip_count = 0;                                       \
81         static int thistogram[32] = {0};                                  \
82         thistogram[av_log2(tdiff)]++;                                     \
83         if (tcount < 2                ||                                  \
84             (tdiff) < 8 * tsum / tcount ||                                \
85             (tdiff) < 2000) {                                             \
86             tsum += (tdiff);                                              \
87             tcount++;                                                     \
88         } else                                                            \
89             tskip_count++;                                                \
90         if (((tcount + tskip_count) & (tcount + tskip_count - 1)) == 0) { \
91             int i;                                                        \
92             av_log(NULL, AV_LOG_ERROR,                                    \
93                    "%7" PRIu64 " " FF_TIMER_UNITS " in %s,%8d runs,%7d skips",\
94                    tsum * 10 / tcount, id, tcount, tskip_count);          \
95             for (i = 0; i < 32; i++)                                      \
96                 av_log(NULL, AV_LOG_VERBOSE, " %2d", av_log2(2*thistogram[i]));\
97             av_log(NULL, AV_LOG_ERROR, "\n");                             \
98         }                                                                 \
99     }
100 
101 #if CONFIG_LINUX_PERF
102 
103 #define START_TIMER                                                         \
104     static int linux_perf_fd;                                               \
105     uint64_t tperf;                                                         \
106     if (!linux_perf_fd) {                                                   \
107         struct perf_event_attr attr = {                                     \
108             .type           = PERF_TYPE_HARDWARE,                           \
109             .size           = sizeof(struct perf_event_attr),               \
110             .config         = PERF_COUNT_HW_CPU_CYCLES,                     \
111             .disabled       = 1,                                            \
112             .exclude_kernel = 1,                                            \
113             .exclude_hv     = 1,                                            \
114         };                                                                  \
115         linux_perf_fd = syscall(__NR_perf_event_open, &attr,                \
116                                 0, -1, -1, 0);                              \
117     }                                                                       \
118     if (linux_perf_fd == -1) {                                              \
119         av_log(NULL, AV_LOG_ERROR, "perf_event_open failed: %s\n",          \
120                av_err2str(AVERROR(errno)));                                 \
121     } else {                                                                \
122         ioctl(linux_perf_fd, PERF_EVENT_IOC_RESET, 0);                      \
123         ioctl(linux_perf_fd, PERF_EVENT_IOC_ENABLE, 0);                     \
124     }
125 
126 #define STOP_TIMER(id)                                                      \
127     ioctl(linux_perf_fd, PERF_EVENT_IOC_DISABLE, 0);                        \
128     read(linux_perf_fd, &tperf, sizeof(tperf));                             \
129     TIMER_REPORT(id, tperf)
130 
131 #elif CONFIG_MACOS_KPERF
132 
133 #define START_TIMER                                                         \
134     uint64_t tperf;                                                         \
135     ff_kperf_init();                                                        \
136     tperf = ff_kperf_cycles();
137 
138 #define STOP_TIMER(id)                                                      \
139     TIMER_REPORT(id, ff_kperf_cycles() - tperf);
140 
141 #elif defined(AV_READ_TIME)
142 #define START_TIMER                             \
143     uint64_t tend;                              \
144     uint64_t tstart = AV_READ_TIME();           \
145 
146 #define STOP_TIMER(id)                                                    \
147     tend = AV_READ_TIME();                                                \
148     TIMER_REPORT(id, tend - tstart)
149 #else
150 #define START_TIMER
151 #define STOP_TIMER(id) { }
152 #endif
153 
154 #endif /* AVUTIL_TIMER_H */
155