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