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Diffstat (limited to 'sysdeps/unix/clock_gettime.c')
-rw-r--r--sysdeps/unix/clock_gettime.c63
1 files changed, 60 insertions, 3 deletions
diff --git a/sysdeps/unix/clock_gettime.c b/sysdeps/unix/clock_gettime.c
index 854cb979c2..7ea75ba00f 100644
--- a/sysdeps/unix/clock_gettime.c
+++ b/sysdeps/unix/clock_gettime.c
@@ -17,14 +17,30 @@
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>
-#ifndef EXTRA_CLOCK_CASES
-# define EXTRA_CLOCK_CASES
+#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)
@@ -41,7 +57,48 @@ clock_gettime (clockid_t clock_id, struct timespec *tp)
TIMEVAL_TO_TIMESPEC (&tv, tp);
break;
- EXTRA_CLOCK_CASES
+#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);