libavutil/timer.h

   1 /**
   2  * @file libavutil/timer.h
   3  * high precision timer, useful to profile code
   4  *
   5  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
   6  *
   7  * This file is part of FFmpeg.
   8  *
   9  * FFmpeg is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * FFmpeg is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with FFmpeg; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 #ifndef AVUTIL_TIMER_H
  25 #define AVUTIL_TIMER_H
  26
  27 #include <stdlib.h>
  28 #include <stdint.h>
  29 #include "config.h"
  30
  31 #if ARCH_X86 || ARCH_PPC || ARCH_BFIN
  32 #define AV_READ_TIME read_time
  33 #if ARCH_X86
  34 static inline uint64_t read_time(void)
  35 {
  36     uint32_t a, d;
  37     __asm__ volatile("rdtsc\n\t"
  38                  : "=a" (a), "=d" (d));
  39     return ((uint64_t)d << 32) + a;
  40 }
  41 #elif ARCH_BFIN
  42 static inline uint64_t read_time(void)
  43 {
  44     union {
  45         struct {
  46             unsigned lo;
  47             unsigned hi;
  48         } p;
  49         unsigned long long c;
  50     } t;
  51     __asm__ volatile ("%0=cycles; %1=cycles2;" : "=d" (t.p.lo), "=d" (t.p.hi));
  52     return t.c;
  53 }
  54 #else //FIXME check ppc64
  55 static inline uint64_t read_time(void)
  56 {
  57     uint32_t tbu, tbl, temp;
  58
  59      /* from section 2.2.1 of the 32-bit PowerPC PEM */
  60      __asm__ volatile(
  61          "1:\n"
  62          "mftbu  %2\n"
  63          "mftb   %0\n"
  64          "mftbu  %1\n"
  65          "cmpw   %2,%1\n"
  66          "bne    1b\n"
  67      : "=r"(tbl), "=r"(tbu), "=r"(temp)
  68      :
  69      : "cc");
  70
  71      return (((uint64_t)tbu)<<32) | (uint64_t)tbl;
  72 }
  73 #endif
  74 #elif HAVE_GETHRTIME
  75 #define AV_READ_TIME gethrtime
  76 #endif
  77
  78 #ifdef AV_READ_TIME
  79 #define START_TIMER \
  80 uint64_t tend;\
  81 uint64_t tstart= AV_READ_TIME();\
  82
  83 #define STOP_TIMER(id) \
  84 tend= AV_READ_TIME();\
  85 {\
  86     static uint64_t tsum=0;\
  87     static int tcount=0;\
  88     static int tskip_count=0;\
  89     if(tcount<2 || tend - tstart < 8*tsum/tcount || tend - tstart < 2000){\
  90         tsum+= tend - tstart;\
  91         tcount++;\
  92     }else\
  93         tskip_count++;\
  94     if(((tcount+tskip_count)&(tcount+tskip_count-1))==0){\
  95         av_log(NULL, AV_LOG_ERROR, "%"PRIu64" dezicycles in %s, %d runs, %d skips\n",\
  96                tsum*10/tcount, id, tcount, tskip_count);\
  97     }\
  98 }
  99 #else
 100 #define START_TIMER
 101 #define STOP_TIMER(id) {}
 102 #endif
 103
 104 #endif /* AVUTIL_TIMER_H */