diff options
Diffstat (limited to 'sysdeps/unix/clock_gettime.c')
| -rw-r--r-- | sysdeps/unix/clock_gettime.c | 63 |
1 files changed, 60 insertions, 3 deletions
diff --git a/sysdeps/unix/clock_gettime.c b/sysdeps/unix/clock_gettime.c index 854cb97..7ea75ba 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); |