sched_setaffinity.c 2.8 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192
  1. /* Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. The GNU C Library is free software; you can redistribute it and/or
  4. modify it under the terms of the GNU Lesser General Public
  5. License as published by the Free Software Foundation; either
  6. version 2.1 of the License, or (at your option) any later version.
  7. The GNU C Library is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  10. Lesser General Public License for more details.
  11. You should have received a copy of the GNU Lesser General Public
  12. License along with the GNU C Library; if not, write to the Free
  13. Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  14. 02111-1307 USA. */
  15. #include <features.h>
  16. #ifdef __USE_GNU
  17. #include <sched.h>
  18. #include <sys/types.h>
  19. #include <sys/syscall.h>
  20. #ifdef INTERNAL_SYSCALL /* remove this when all archs has this #defined */
  21. #include <string.h>
  22. #include <unistd.h>
  23. #include <sys/param.h>
  24. #include <alloca.h>
  25. #if defined __NR_sched_setaffinity
  26. libc_hidden_proto(getpid)
  27. #define __NR___syscall_sched_setaffinity __NR_sched_setaffinity
  28. static __inline__ _syscall3(int, __syscall_sched_setaffinity, __kernel_pid_t, pid,
  29. size_t, cpusetsize, cpu_set_t *, cpuset);
  30. static size_t __kernel_cpumask_size;
  31. int sched_setaffinity(pid_t pid, size_t cpusetsize, const cpu_set_t *cpuset)
  32. {
  33. size_t cnt;
  34. if (unlikely (__kernel_cpumask_size == 0)) {
  35. INTERNAL_SYSCALL_DECL (err);
  36. int res;
  37. size_t psize = 128;
  38. void *p = alloca (psize);
  39. while (res = INTERNAL_SYSCALL (sched_getaffinity, err, 3, getpid (),
  40. psize, p),
  41. INTERNAL_SYSCALL_ERROR_P (res, err)
  42. && INTERNAL_SYSCALL_ERRNO (res, err) == EINVAL)
  43. p = extend_alloca (p, psize, 2 * psize);
  44. if (res == 0 || INTERNAL_SYSCALL_ERROR_P (res, err)) {
  45. __set_errno (INTERNAL_SYSCALL_ERRNO (res, err));
  46. return -1;
  47. }
  48. __kernel_cpumask_size = res;
  49. }
  50. /* We now know the size of the kernel cpumask_t. Make sure the user
  51. does not request to set a bit beyond that. */
  52. for (cnt = __kernel_cpumask_size; cnt < cpusetsize; ++cnt)
  53. if (((char *) cpuset)[cnt] != '\0') {
  54. /* Found a nonzero byte. This means the user request cannot be
  55. fulfilled. */
  56. __set_errno (EINVAL);
  57. return -1;
  58. }
  59. return INLINE_SYSCALL (sched_setaffinity, 3, pid, cpusetsize, cpuset);
  60. }
  61. #else
  62. #define ___HAVE_NO_sched_setaffinity
  63. #endif
  64. #else
  65. #define ___HAVE_NO_sched_setaffinity
  66. #endif
  67. #if defined ___HAVE_NO_sched_setaffinity && defined __UCLIBC_HAS_STUBS__
  68. int sched_setaffinity(pid_t pid, size_t cpusetsize, const cpu_set_t *cpuset)
  69. {
  70. __set_errno(ENOSYS);
  71. return -1;
  72. }
  73. #endif
  74. #endif /* __USE_GNU */