nptl/sysdeps/unix/sysv/linux/pthread_getcpuclockid.c

   1 /* pthread_getcpuclockid -- Get POSIX clockid_t for a pthread_t.  Linux version
   2    Copyright (C) 2000-2014 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If
  17    not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <pthreadP.h>
  21 #include <sys/time.h>
  22 #include <tls.h>
  23 #include <kernel-features.h>
  24 #include <kernel-posix-cpu-timers.h>
  25
  26
  27 int
  28 pthread_getcpuclockid (threadid, clockid)
  29      pthread_t threadid;
  30      clockid_t *clockid;
  31 {
  32   struct pthread *pd = (struct pthread *) threadid;
  33
  34   /* Make sure the descriptor is valid.  */
  35   if (INVALID_TD_P (pd))
  36     /* Not a valid thread handle.  */
  37     return ESRCH;
  38
  39   /* The clockid_t value is a simple computation from the TID.  */
  40
  41   const clockid_t tidclock = MAKE_THREAD_CPUCLOCK (pd->tid, CPUCLOCK_SCHED);
  42
  43   *clockid = tidclock;
  44   return 0;
  45 }