Subversion Repositories openrisc_2011-10-31

/* Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, write to the Free

   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA

   02111-1307 USA.  */

#include <errno.h>

#include <stdint.h>

#include <time.h>

#include <sys/time.h>

#include <libc-internal.h>

#include <hp-timing.h>

#if HP_TIMING_AVAIL

/* Clock frequency of the processor.  We make it a 64-bit variable

   because some jokers are already playing with processors with more

   than 4GHz.  */

static hp_timing_t freq;

/* We need the starting time for the process.  */

extern hp_timing_t _dl_cpuclock_offset;

/* This function is defined in the thread library.  */

extern int __pthread_clock_gettime (hp_timing_t freq, struct timespec *tp)

     __attribute__ ((__weak__));

#endif

/* Get current value of CLOCK and store it in TP.  */

int

clock_gettime (clockid_t clock_id, struct timespec *tp)

{

  struct timeval tv;

  int retval = -1;

  switch (clock_id)

    {

    case CLOCK_REALTIME:

      retval = gettimeofday (&tv, NULL);

      if (retval == 0)

        /* Convert into `timespec'.  */

        TIMEVAL_TO_TIMESPEC (&tv, tp);

      break;

#if HP_TIMING_AVAIL

    case CLOCK_PROCESS_CPUTIME_ID:

    case CLOCK_THREAD_CPUTIME_ID:

      {

        hp_timing_t tsc;

        if (__builtin_expect (freq == 0, 0))

          {

            /* This can only happen if we haven't initialized the `freq'

               variable yet.  Do this now. We don't have to protect this

               code against multiple execution since all of them should

               lead to the same result.  */

            freq = __get_clockfreq ();

            if (__builtin_expect (freq == 0, 0))

              /* Something went wrong.  */

              break;

          }

        if (clock_id == CLOCK_THREAD_CPUTIME_ID

            && __pthread_clock_gettime != NULL)

          {

            retval = __pthread_clock_gettime (freq, tp);

            break;

          }

        /* Get the current counter.  */

        HP_TIMING_NOW (tsc);

        /* Compute the offset since the start time of the process.  */

        tsc -= _dl_cpuclock_offset;

        /* Compute the seconds.  */

        tp->tv_sec = tsc / freq;

        /* And the nanoseconds.  This computation should be stable until

           we get machines with about 16GHz frequency.  */

        tp->tv_nsec = ((tsc % freq) * UINT64_C (1000000000)) / freq;

        retval = 0;

      }

    break;

#endif

    default:

      __set_errno (EINVAL);

      break;

    }

  return retval;

}