sysdeps/unix/sysv/linux/sched_getaffinity.c

   1 /* Copyright (C) 2002-2018 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library 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    The GNU C Library 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 the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <sched.h>
  20 #include <string.h>
  21 #include <sysdep.h>
  22 #include <sys/param.h>
  23 #include <sys/types.h>
  24 #include <shlib-compat.h>
  25
  26
  27 #ifdef __NR_sched_getaffinity
  28 # if SHLIB_COMPAT (libc, GLIBC_2_3_3, GLIBC_2_3_4)
  29 extern int __sched_getaffinity_new (pid_t, size_t, cpu_set_t *);
  30 libc_hidden_proto (__sched_getaffinity_new)
  31 # endif
  32
  33 int
  34 __sched_getaffinity_new (pid_t pid, size_t cpusetsize, cpu_set_t *cpuset)
  35 {
  36   int res = INLINE_SYSCALL (sched_getaffinity, 3, pid,
  37                             MIN (INT_MAX, cpusetsize), cpuset);
  38   if (res != -1)
  39     {
  40       /* Clean the rest of the memory the kernel didn't do.  */
  41       memset ((char *) cpuset + res, '\0', cpusetsize - res);
  42
  43       res = 0;
  44     }
  45   return res;
  46 }
  47 versioned_symbol (libc, __sched_getaffinity_new, sched_getaffinity,
  48                   GLIBC_2_3_4);
  49
  50
  51 # if SHLIB_COMPAT (libc, GLIBC_2_3_3, GLIBC_2_3_4)
  52 libc_hidden_def (__sched_getaffinity_new)
  53
  54 int
  55 attribute_compat_text_section
  56 __sched_getaffinity_old (pid_t pid, cpu_set_t *cpuset)
  57 {
  58   /* The old interface by default assumed a 1024 processor bitmap.  */
  59   return __sched_getaffinity_new (pid, 128, cpuset);
  60 }
  61 compat_symbol (libc, __sched_getaffinity_old, sched_getaffinity, GLIBC_2_3_3);
  62 # endif
  63 #else
  64 # include <posix/sched_getaffinity.c>
  65 #endif