pthread_setschedprio.c 2.0 KB

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  1. /* Copyright (C) 2002, 2003, 2004, 2007 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
  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. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. #include <errno.h>
  16. #include <sched.h>
  17. #include <string.h>
  18. #include <sched.h>
  19. #include "pthreadP.h"
  20. #include <lowlevellock.h>
  21. int
  22. pthread_setschedprio (
  23. pthread_t threadid,
  24. int prio)
  25. {
  26. struct pthread *pd = (struct pthread *) threadid;
  27. /* Make sure the descriptor is valid. */
  28. if (INVALID_TD_P (pd))
  29. /* Not a valid thread handle. */
  30. return ESRCH;
  31. int result = 0;
  32. struct sched_param param;
  33. param.sched_priority = prio;
  34. lll_lock (pd->lock, LLL_PRIVATE);
  35. /* If the thread should have higher priority because of some
  36. PTHREAD_PRIO_PROTECT mutexes it holds, adjust the priority. */
  37. if (__builtin_expect (pd->tpp != NULL, 0) && pd->tpp->priomax > prio)
  38. param.sched_priority = pd->tpp->priomax;
  39. /* Try to set the scheduler information. */
  40. if (__builtin_expect (sched_setparam (pd->tid, &param) == -1, 0))
  41. result = errno;
  42. else
  43. {
  44. /* We succeeded changing the kernel information. Reflect this
  45. change in the thread descriptor. */
  46. param.sched_priority = prio;
  47. memcpy (&pd->schedparam, &param, sizeof (struct sched_param));
  48. pd->flags |= ATTR_FLAG_SCHED_SET;
  49. }
  50. lll_unlock (pd->lock, LLL_PRIVATE);
  51. return result;
  52. }