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FFmpeg/libavutil/cpu.c

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  1. /*

  2.  * This file is part of FFmpeg.

  3.  *

  4.  * FFmpeg is free software; you can redistribute it and/or

  5.  * modify it under the terms of the GNU Lesser General Public

  6.  * License as published by the Free Software Foundation; either

  7.  * version 2.1 of the License, or (at your option) any later version.

  8.  *

  9.  * FFmpeg is distributed in the hope that it will be useful,

  10.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  11.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  12.  * Lesser General Public License for more details.

  13.  *

  14.  * You should have received a copy of the GNU Lesser General Public

  15.  * License along with FFmpeg; if not, write to the Free Software

  16.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  17.  */

  18. 

  19. #include <stdint.h>

  20. 

  21. #include "cpu.h"

  22. #include "cpu_internal.h"

  23. #include "config.h"

  24. #include "opt.h"

  25. #include "common.h"

  26. 

  27. #if HAVE_SCHED_GETAFFINITY

  28. #ifndef _GNU_SOURCE

  29. # define _GNU_SOURCE

  30. #endif

  31. #include <sched.h>

  32. #endif

  33. #if HAVE_GETPROCESSAFFINITYMASK || HAVE_WINRT

  34. #include <windows.h>

  35. #endif

  36. #if HAVE_SYSCTL

  37. #if HAVE_SYS_PARAM_H

  38. #include <sys/param.h>

  39. #endif

  40. #include <sys/types.h>

  41. #include <sys/sysctl.h>

  42. #endif

  43. #if HAVE_UNISTD_H

  44. #include <unistd.h>

  45. #endif

  46. 

  47. static int cpu_flags = -1;

  48. 

  49. static int get_cpu_flags(void)

  50. {

  51.     if (ARCH_AARCH64)

  52.         return ff_get_cpu_flags_aarch64();

  53.     if (ARCH_ARM)

  54.         return ff_get_cpu_flags_arm();

  55.     if (ARCH_PPC)

  56.         return ff_get_cpu_flags_ppc();

  57.     if (ARCH_X86)

  58.         return ff_get_cpu_flags_x86();

  59.     return 0;

  60. }

  61. 

  62. void av_force_cpu_flags(int arg){

  63.     if (   (arg & ( AV_CPU_FLAG_3DNOW    |

  64.                     AV_CPU_FLAG_3DNOWEXT |

  65.                     AV_CPU_FLAG_MMXEXT   |

  66.                     AV_CPU_FLAG_SSE      |

  67.                     AV_CPU_FLAG_SSE2     |

  68.                     AV_CPU_FLAG_SSE2SLOW |

  69.                     AV_CPU_FLAG_SSE3     |

  70.                     AV_CPU_FLAG_SSE3SLOW |

  71.                     AV_CPU_FLAG_SSSE3    |

  72.                     AV_CPU_FLAG_SSE4     |

  73.                     AV_CPU_FLAG_SSE42    |

  74.                     AV_CPU_FLAG_AVX      |

  75.                     AV_CPU_FLAG_AVXSLOW  |

  76.                     AV_CPU_FLAG_XOP      |

  77.                     AV_CPU_FLAG_FMA3     |

  78.                     AV_CPU_FLAG_FMA4     |

  79.                     AV_CPU_FLAG_AVX2     ))

  80.         && !(arg & AV_CPU_FLAG_MMX)) {

  81.         av_log(NULL, AV_LOG_WARNING, "MMX implied by specified flags\n");

  82.         arg |= AV_CPU_FLAG_MMX;

  83.     }

  84. 

  85.     cpu_flags = arg;

  86. }

  87. 

  88. int av_get_cpu_flags(void)

  89. {

  90.     int flags = cpu_flags;

  91.     if (flags == -1) {

  92.         flags = get_cpu_flags();

  93.         cpu_flags = flags;

  94.     }

  95.     return flags;

  96. }

  97. 

  98. void av_set_cpu_flags_mask(int mask)

  99. {

  100.     cpu_flags = get_cpu_flags() & mask;

  101. }

  102. 

  103. int av_parse_cpu_flags(const char *s)

  104. {

  105. #define CPUFLAG_MMXEXT   (AV_CPU_FLAG_MMX      | AV_CPU_FLAG_MMXEXT | AV_CPU_FLAG_CMOV)

  106. #define CPUFLAG_3DNOW    (AV_CPU_FLAG_3DNOW    | AV_CPU_FLAG_MMX)

  107. #define CPUFLAG_3DNOWEXT (AV_CPU_FLAG_3DNOWEXT | CPUFLAG_3DNOW)

  108. #define CPUFLAG_SSE      (AV_CPU_FLAG_SSE      | CPUFLAG_MMXEXT)

  109. #define CPUFLAG_SSE2     (AV_CPU_FLAG_SSE2     | CPUFLAG_SSE)

  110. #define CPUFLAG_SSE2SLOW (AV_CPU_FLAG_SSE2SLOW | CPUFLAG_SSE2)

  111. #define CPUFLAG_SSE3     (AV_CPU_FLAG_SSE3     | CPUFLAG_SSE2)

  112. #define CPUFLAG_SSE3SLOW (AV_CPU_FLAG_SSE3SLOW | CPUFLAG_SSE3)

  113. #define CPUFLAG_SSSE3    (AV_CPU_FLAG_SSSE3    | CPUFLAG_SSE3)

  114. #define CPUFLAG_SSE4     (AV_CPU_FLAG_SSE4     | CPUFLAG_SSSE3)

  115. #define CPUFLAG_SSE42    (AV_CPU_FLAG_SSE42    | CPUFLAG_SSE4)

  116. #define CPUFLAG_AVX      (AV_CPU_FLAG_AVX      | CPUFLAG_SSE42)

  117. #define CPUFLAG_AVXSLOW  (AV_CPU_FLAG_AVXSLOW  | CPUFLAG_AVX)

  118. #define CPUFLAG_XOP      (AV_CPU_FLAG_XOP      | CPUFLAG_AVX)

  119. #define CPUFLAG_FMA3     (AV_CPU_FLAG_FMA3     | CPUFLAG_AVX)

  120. #define CPUFLAG_FMA4     (AV_CPU_FLAG_FMA4     | CPUFLAG_AVX)

  121. #define CPUFLAG_AVX2     (AV_CPU_FLAG_AVX2     | CPUFLAG_AVX)

  122. #define CPUFLAG_BMI2     (AV_CPU_FLAG_BMI2     | AV_CPU_FLAG_BMI1)

  123. #define CPUFLAG_AESNI    (AV_CPU_FLAG_AESNI    | CPUFLAG_SSE42)

  124.     static const AVOption cpuflags_opts[] = {

  125.         { "flags"   , NULL, 0, AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT64_MIN, INT64_MAX, .unit = "flags" },

  126. #if   ARCH_PPC

  127.         { "altivec" , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ALTIVEC  },    .unit = "flags" },

  128. #elif ARCH_X86

  129.         { "mmx"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MMX      },    .unit = "flags" },

  130.         { "mmxext"  , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_MMXEXT       },    .unit = "flags" },

  131.         { "sse"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSE          },    .unit = "flags" },

  132.         { "sse2"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSE2         },    .unit = "flags" },

  133.         { "sse2slow", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSE2SLOW     },    .unit = "flags" },

  134.         { "sse3"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSE3         },    .unit = "flags" },

  135.         { "sse3slow", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSE3SLOW     },    .unit = "flags" },

  136.         { "ssse3"   , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSSE3        },    .unit = "flags" },

  137.         { "atom"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ATOM     },    .unit = "flags" },

  138.         { "sse4.1"  , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSE4         },    .unit = "flags" },

  139.         { "sse4.2"  , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_SSE42        },    .unit = "flags" },

  140.         { "avx"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_AVX          },    .unit = "flags" },

  141.         { "avxslow" , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_AVXSLOW      },    .unit = "flags" },

  142.         { "xop"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_XOP          },    .unit = "flags" },

  143.         { "fma3"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_FMA3         },    .unit = "flags" },

  144.         { "fma4"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_FMA4         },    .unit = "flags" },

  145.         { "avx2"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_AVX2         },    .unit = "flags" },

  146.         { "bmi1"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_BMI1     },    .unit = "flags" },

  147.         { "bmi2"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_BMI2         },    .unit = "flags" },

  148.         { "3dnow"   , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_3DNOW        },    .unit = "flags" },

  149.         { "3dnowext", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_3DNOWEXT     },    .unit = "flags" },

  150.         { "cmov",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_CMOV     },    .unit = "flags" },

  151.         { "aesni"   , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPUFLAG_AESNI        },    .unit = "flags" },

  152. #elif ARCH_ARM

  153.         { "armv5te",  NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV5TE  },    .unit = "flags" },

  154.         { "armv6",    NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV6    },    .unit = "flags" },

  155.         { "armv6t2",  NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV6T2  },    .unit = "flags" },

  156.         { "vfp",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFP      },    .unit = "flags" },

  157.         { "vfp_vm",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFP_VM   },    .unit = "flags" },

  158.         { "vfpv3",    NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFPV3    },    .unit = "flags" },

  159.         { "neon",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_NEON     },    .unit = "flags" },

  160. #elif ARCH_AARCH64

  161.         { "armv8",    NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV8    },    .unit = "flags" },

  162.         { "neon",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_NEON     },    .unit = "flags" },

  163.         { "vfp",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFP      },    .unit = "flags" },

  164. #endif

  165.         { NULL },

  166.     };

  167.     static const AVClass class = {

  168.         .class_name = "cpuflags",

  169.         .item_name  = av_default_item_name,

  170.         .option     = cpuflags_opts,

  171.         .version    = LIBAVUTIL_VERSION_INT,

  172.     };

  173. 

  174.     int flags = 0, ret;

  175.     const AVClass *pclass = &class;

  176. 

  177.     if ((ret = av_opt_eval_flags(&pclass, &cpuflags_opts[0], s, &flags)) < 0)

  178.         return ret;

  179. 

  180.     return flags & INT_MAX;

  181. }

  182. 

  183. int av_parse_cpu_caps(unsigned *flags, const char *s)

  184. {

  185.         static const AVOption cpuflags_opts[] = {

  186.         { "flags"   , NULL, 0, AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT64_MIN, INT64_MAX, .unit = "flags" },

  187. #if   ARCH_PPC

  188.         { "altivec" , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ALTIVEC  },    .unit = "flags" },

  189. #elif ARCH_X86

  190.         { "mmx"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MMX      },    .unit = "flags" },

  191.         { "mmx2"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MMX2     },    .unit = "flags" },

  192.         { "mmxext"  , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MMX2     },    .unit = "flags" },

  193.         { "sse"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSE      },    .unit = "flags" },

  194.         { "sse2"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSE2     },    .unit = "flags" },

  195.         { "sse2slow", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSE2SLOW },    .unit = "flags" },

  196.         { "sse3"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSE3     },    .unit = "flags" },

  197.         { "sse3slow", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSE3SLOW },    .unit = "flags" },

  198.         { "ssse3"   , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSSE3    },    .unit = "flags" },

  199.         { "atom"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ATOM     },    .unit = "flags" },

  200.         { "sse4.1"  , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSE4     },    .unit = "flags" },

  201.         { "sse4.2"  , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SSE42    },    .unit = "flags" },

  202.         { "avx"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_AVX      },    .unit = "flags" },

  203.         { "avxslow" , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_AVXSLOW  },    .unit = "flags" },

  204.         { "xop"     , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_XOP      },    .unit = "flags" },

  205.         { "fma3"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_FMA3     },    .unit = "flags" },

  206.         { "fma4"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_FMA4     },    .unit = "flags" },

  207.         { "avx2"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_AVX2     },    .unit = "flags" },

  208.         { "bmi1"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_BMI1     },    .unit = "flags" },

  209.         { "bmi2"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_BMI2     },    .unit = "flags" },

  210.         { "3dnow"   , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_3DNOW    },    .unit = "flags" },

  211.         { "3dnowext", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_3DNOWEXT },    .unit = "flags" },

  212.         { "cmov",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_CMOV     },    .unit = "flags" },

  213.         { "aesni",    NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_AESNI    },    .unit = "flags" },

  214. 

  215. #define CPU_FLAG_P2 AV_CPU_FLAG_CMOV | AV_CPU_FLAG_MMX

  216. #define CPU_FLAG_P3 CPU_FLAG_P2 | AV_CPU_FLAG_MMX2 | AV_CPU_FLAG_SSE

  217. #define CPU_FLAG_P4 CPU_FLAG_P3| AV_CPU_FLAG_SSE2

  218.         { "pentium2", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPU_FLAG_P2          },    .unit = "flags" },

  219.         { "pentium3", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPU_FLAG_P3          },    .unit = "flags" },

  220.         { "pentium4", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPU_FLAG_P4          },    .unit = "flags" },

  221. 

  222. #define CPU_FLAG_K62 AV_CPU_FLAG_MMX | AV_CPU_FLAG_3DNOW

  223. #define CPU_FLAG_ATHLON   CPU_FLAG_K62 | AV_CPU_FLAG_CMOV | AV_CPU_FLAG_3DNOWEXT | AV_CPU_FLAG_MMX2

  224. #define CPU_FLAG_ATHLONXP CPU_FLAG_ATHLON | AV_CPU_FLAG_SSE

  225. #define CPU_FLAG_K8  CPU_FLAG_ATHLONXP | AV_CPU_FLAG_SSE2

  226.         { "k6",       NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MMX      },    .unit = "flags" },

  227.         { "k62",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPU_FLAG_K62         },    .unit = "flags" },

  228.         { "athlon",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPU_FLAG_ATHLON      },    .unit = "flags" },

  229.         { "athlonxp", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPU_FLAG_ATHLONXP    },    .unit = "flags" },

  230.         { "k8",       NULL, 0, AV_OPT_TYPE_CONST, { .i64 = CPU_FLAG_K8          },    .unit = "flags" },

  231. #elif ARCH_ARM

  232.         { "armv5te",  NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV5TE  },    .unit = "flags" },

  233.         { "armv6",    NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV6    },    .unit = "flags" },

  234.         { "armv6t2",  NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV6T2  },    .unit = "flags" },

  235.         { "vfp",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFP      },    .unit = "flags" },

  236.         { "vfp_vm",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFP_VM   },    .unit = "flags" },

  237.         { "vfpv3",    NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFPV3    },    .unit = "flags" },

  238.         { "neon",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_NEON     },    .unit = "flags" },

  239.         { "setend",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_SETEND   },    .unit = "flags" },

  240. #elif ARCH_AARCH64

  241.         { "armv8",    NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_ARMV8    },    .unit = "flags" },

  242.         { "neon",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_NEON     },    .unit = "flags" },

  243.         { "vfp",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_VFP      },    .unit = "flags" },

  244. #endif

  245.         { NULL },

  246.     };

  247.     static const AVClass class = {

  248.         .class_name = "cpuflags",

  249.         .item_name  = av_default_item_name,

  250.         .option     = cpuflags_opts,

  251.         .version    = LIBAVUTIL_VERSION_INT,

  252.     };

  253.     const AVClass *pclass = &class;

  254. 

  255.     return av_opt_eval_flags(&pclass, &cpuflags_opts[0], s, flags);

  256. }

  257. 

  258. int av_cpu_count(void)

  259. {

  260.     static volatile int printed;

  261. 

  262.     int nb_cpus = 1;

  263. #if HAVE_WINRT

  264.     SYSTEM_INFO sysinfo;

  265. #endif

  266. #if HAVE_SCHED_GETAFFINITY && defined(CPU_COUNT)

  267.     cpu_set_t cpuset;

  268. 

  269.     CPU_ZERO(&cpuset);

  270. 

  271.     if (!sched_getaffinity(0, sizeof(cpuset), &cpuset))

  272.         nb_cpus = CPU_COUNT(&cpuset);

  273. #elif HAVE_GETPROCESSAFFINITYMASK

  274.     DWORD_PTR proc_aff, sys_aff;

  275.     if (GetProcessAffinityMask(GetCurrentProcess(), &proc_aff, &sys_aff))

  276.         nb_cpus = av_popcount64(proc_aff);

  277. #elif HAVE_SYSCTL && defined(HW_NCPU)

  278.     int mib[2] = { CTL_HW, HW_NCPU };

  279.     size_t len = sizeof(nb_cpus);

  280. 

  281.     if (sysctl(mib, 2, &nb_cpus, &len, NULL, 0) == -1)

  282.         nb_cpus = 0;

  283. #elif HAVE_SYSCONF && defined(_SC_NPROC_ONLN)

  284.     nb_cpus = sysconf(_SC_NPROC_ONLN);

  285. #elif HAVE_SYSCONF && defined(_SC_NPROCESSORS_ONLN)

  286.     nb_cpus = sysconf(_SC_NPROCESSORS_ONLN);

  287. #elif HAVE_WINRT

  288.     GetNativeSystemInfo(&sysinfo);

  289.     nb_cpus = sysinfo.dwNumberOfProcessors;

  290. #endif

  291. 

  292.     if (!printed) {

  293.         av_log(NULL, AV_LOG_DEBUG, "detected %d logical cores\n", nb_cpus);

  294.         printed = 1;

  295.     }

  296. 

  297.     return nb_cpus;

  298. }