/* 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, see <http://www.gnu.org/licenses/>. */ #include <errno.h> #include <stdlib.h> #include <time.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