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Diffstat (limited to 'libpthread/linuxthreads/sysdeps/pthread/getcpuclockid.c')
-rw-r--r--libpthread/linuxthreads/sysdeps/pthread/getcpuclockid.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/sysdeps/pthread/getcpuclockid.c b/libpthread/linuxthreads/sysdeps/pthread/getcpuclockid.c
new file mode 100644
index 000000000..1c64e6c2b
--- /dev/null
+++ b/libpthread/linuxthreads/sysdeps/pthread/getcpuclockid.c
@@ -0,0 +1,117 @@
+/* pthread_getcpuclockid -- Get POSIX clockid_t for a pthread_t. Linux version
+ Copyright (C) 2000, 2001, 2004, 2005 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 <pthread.h>
+#include <sys/time.h>
+#include <time.h>
+#include <internals.h>
+#include <spinlock.h>
+#include <kernel-features.h>
+#include <kernel-posix-cpu-timers.h>
+
+
+#if !(__ASSUME_POSIX_CPU_TIMERS > 0)
+int __libc_missing_posix_cpu_timers attribute_hidden;
+#endif
+#if !(__ASSUME_POSIX_TIMERS > 0)
+int __libc_missing_posix_timers attribute_hidden;
+#endif
+
+int
+pthread_getcpuclockid (pthread_t thread_id, clockid_t *clock_id)
+{
+#ifdef __NR_clock_getres
+ pthread_handle handle = thread_handle(thread_id);
+ int pid;
+
+ __pthread_lock (&handle->h_lock, NULL);
+ if (nonexisting_handle (handle, thread_id))
+ {
+ __pthread_unlock (&handle->h_lock);
+ return ESRCH;
+ }
+ pid = handle->h_descr->p_pid;
+ __pthread_unlock (&handle->h_lock);
+
+ /* The clockid_t value is a simple computation from the PID.
+ But we do a clock_getres call to validate it if we aren't
+ yet sure we have the kernel support. */
+
+ const clockid_t pidclock = MAKE_PROCESS_CPUCLOCK (pid, CPUCLOCK_SCHED);
+
+# if !(__ASSUME_POSIX_CPU_TIMERS > 0)
+# if !(__ASSUME_POSIX_TIMERS > 0)
+ if (__libc_missing_posix_timers && !__libc_missing_posix_cpu_timers)
+ __libc_missing_posix_cpu_timers = 1;
+# endif
+ if (!__libc_missing_posix_cpu_timers)
+ {
+ INTERNAL_SYSCALL_DECL (err);
+ int r = INTERNAL_SYSCALL (clock_getres, err, 2, pidclock, NULL);
+ if (!INTERNAL_SYSCALL_ERROR_P (r, err))
+# endif
+ {
+ *clock_id = pidclock;
+ return 0;
+ }
+
+# if !(__ASSUME_POSIX_CPU_TIMERS > 0)
+# if !(__ASSUME_POSIX_TIMERS > 0)
+ if (INTERNAL_SYSCALL_ERRNO (r, err) == ENOSYS)
+ {
+ /* The kernel doesn't support these calls at all. */
+ __libc_missing_posix_timers = 1;
+ __libc_missing_posix_cpu_timers = 1;
+ }
+ else
+# endif
+ if (INTERNAL_SYSCALL_ERRNO (r, err) == EINVAL)
+ {
+ /* The kernel doesn't support these clocks at all. */
+ __libc_missing_posix_cpu_timers = 1;
+ }
+ else
+ return INTERNAL_SYSCALL_ERRNO (r, err);
+ }
+# endif
+#endif
+
+#ifdef CLOCK_THREAD_CPUTIME_ID
+ /* We need to store the thread ID in the CLOCKID variable together
+ with a number identifying the clock. We reserve the low 3 bits
+ for the clock ID and the rest for the thread ID. This is
+ problematic if the thread ID is too large. But 29 bits should be
+ fine.
+
+ If some day more clock IDs are needed the ID part can be
+ enlarged. The IDs are entirely internal. */
+ if (2 * PTHREAD_THREADS_MAX
+ >= 1 << (8 * sizeof (*clock_id) - CLOCK_IDFIELD_SIZE))
+ return ERANGE;
+
+ /* Store the number. */
+ *clock_id = CLOCK_THREAD_CPUTIME_ID | (thread_id << CLOCK_IDFIELD_SIZE);
+
+ return 0;
+#else
+ /* We don't have a timer for that. */
+ return ENOENT;
+#endif
+}