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-rw-r--r--libpthread/nptl/pthread_clock_gettime.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/libpthread/nptl/pthread_clock_gettime.c b/libpthread/nptl/pthread_clock_gettime.c
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index 000000000..a71174c9c
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+++ b/libpthread/nptl/pthread_clock_gettime.c
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+/* 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