diff options
| -rw-r--r-- | sys/cddl/dev/dtrace/aarch64/dtrace_subr.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/sys/cddl/dev/dtrace/aarch64/dtrace_subr.c b/sys/cddl/dev/dtrace/aarch64/dtrace_subr.c index 6646e51fc191..9bf9f0798bb5 100644 --- a/sys/cddl/dev/dtrace/aarch64/dtrace_subr.c +++ b/sys/cddl/dev/dtrace/aarch64/dtrace_subr.c @@ -153,23 +153,26 @@ dtrace_sync(void) } /* - * DTrace needs a high resolution time function which can - * be called from a probe context and guaranteed not to have - * instrumented with probes itself. + * DTrace needs a high resolution time function which can be called from a + * probe context and guaranteed not to have instrumented with probes itself. * - * Returns nanoseconds since boot. + * Returns nanoseconds since some arbitrary point in time (likely SoC reset?). */ uint64_t -dtrace_gethrtime() +dtrace_gethrtime(void) { - struct timespec curtime; - - dtrace_getnanouptime(&curtime); - - return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec); + uint64_t count, freq; + count = READ_SPECIALREG(cntvct_el0); + freq = READ_SPECIALREG(cntfrq_el0); + return ((1000000000UL * count) / freq); } +/* + * Return a much lower resolution wallclock time based on the system clock + * updated by the timer. If needed, we could add a version interpolated from + * the system clock as is the case with dtrace_gethrtime(). + */ uint64_t dtrace_gethrestime(void) { |