pthread_getschedparam.c 2.2 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 <string.h>
  17. #include "pthreadP.h"
  18. #include <lowlevellock.h>
  19. int
  20. attribute_protected
  21. __pthread_getschedparam (
  22. pthread_t threadid,
  23. int *policy,
  24. struct sched_param *param)
  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. lll_lock (pd->lock, LLL_PRIVATE);
  33. /* The library is responsible for maintaining the values at all
  34. times. If the user uses a interface other than
  35. pthread_setschedparam to modify the scheduler setting it is not
  36. the library's problem. In case the descriptor's values have
  37. not yet been retrieved do it now. */
  38. if ((pd->flags & ATTR_FLAG_SCHED_SET) == 0)
  39. {
  40. if (sched_getparam (pd->tid, &pd->schedparam) != 0)
  41. result = 1;
  42. else
  43. pd->flags |= ATTR_FLAG_SCHED_SET;
  44. }
  45. if ((pd->flags & ATTR_FLAG_POLICY_SET) == 0)
  46. {
  47. pd->schedpolicy = sched_getscheduler (pd->tid);
  48. if (pd->schedpolicy == -1)
  49. result = 1;
  50. else
  51. pd->flags |= ATTR_FLAG_POLICY_SET;
  52. }
  53. if (result == 0)
  54. {
  55. *policy = pd->schedpolicy;
  56. memcpy (param, &pd->schedparam, sizeof (struct sched_param));
  57. }
  58. lll_unlock (pd->lock, LLL_PRIVATE);
  59. return result;
  60. }
  61. strong_alias (__pthread_getschedparam, pthread_getschedparam)