diff options
Diffstat (limited to 'libpthread/nptl/pthread_clock_gettime.c')
-rw-r--r-- | libpthread/nptl/pthread_clock_gettime.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/libpthread/nptl/pthread_clock_gettime.c b/libpthread/nptl/pthread_clock_gettime.c new file mode 100644 index 000000000..a71174c9c --- /dev/null +++ b/libpthread/nptl/pthread_clock_gettime.c @@ -0,0 +1,69 @@ +/* Copyright (C) 2001, 2002, 2003 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; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <errno.h> +#include <stdlib.h> +#include <time.h> +#include <libc-internal.h> +#include "pthreadP.h" + + +#if HP_TIMING_AVAIL +int +__pthread_clock_gettime (clockid_t clock_id, hp_timing_t freq, + struct timespec *tp) +{ + hp_timing_t tsc; + + /* Get the current counter. */ + HP_TIMING_NOW (tsc); + + /* This is the ID of the thread we are looking for. */ + pid_t tid = ((unsigned int) clock_id) >> CLOCK_IDFIELD_SIZE; + + /* Compute the offset since the start time of the process. */ + if (tid == 0 || tid == THREAD_GETMEM (THREAD_SELF, tid)) + /* Our own clock. */ + tsc -= THREAD_GETMEM (THREAD_SELF, cpuclock_offset); + else + { + /* This is more complicated. We have to locate the thread based + on the ID. This means walking the list of existing + threads. */ + struct pthread *thread = __find_thread_by_id (tid); + if (thread == NULL) + { + __set_errno (EINVAL); + return -1; + } + + /* There is a race here. The thread might terminate and the stack + become unusable. But this is the user's problem. */ + tsc -= thread->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) * 1000000000ull) / freq; + + return 0; +} +#endif |