xen_clock(4): Sprinkle dtrace probes.
This commit is contained in:
riastradh
parent
a5ac5faae0
commit
4709656009
|
|
@ -1,4 +1,4 @@
|
|||
/* $NetBSD: xen_clock.c,v 1.8 2020/11/30 17:05:02 bouyer Exp $ */
|
||||
/* $NetBSD: xen_clock.c,v 1.9 2023/05/01 09:03:19 riastradh Exp $ */
|
||||
|
||||
/*-
|
||||
* Copyright (c) 2017, 2018 The NetBSD Foundation, Inc.
|
||||
|
|
@ -36,7 +36,7 @@
|
|||
#endif
|
||||
|
||||
#include <sys/cdefs.h>
|
||||
__KERNEL_RCSID(0, "$NetBSD: xen_clock.c,v 1.8 2020/11/30 17:05:02 bouyer Exp $");
|
||||
__KERNEL_RCSID(0, "$NetBSD: xen_clock.c,v 1.9 2023/05/01 09:03:19 riastradh Exp $");
|
||||
|
||||
#include <sys/param.h>
|
||||
#include <sys/types.h>
|
||||
|
|
@ -49,6 +49,7 @@ __KERNEL_RCSID(0, "$NetBSD: xen_clock.c,v 1.8 2020/11/30 17:05:02 bouyer Exp $")
|
|||
#include <sys/kernel.h>
|
||||
#include <sys/lwp.h>
|
||||
#include <sys/proc.h>
|
||||
#include <sys/sdt.h>
|
||||
#include <sys/sysctl.h>
|
||||
#include <sys/systm.h>
|
||||
#include <sys/time.h>
|
||||
|
|
@ -75,6 +76,50 @@ static uint64_t xen_global_systime_ns(void);
|
|||
static unsigned xen_get_timecount(struct timecounter *);
|
||||
static int xen_timer_handler(void *, struct clockframe *);
|
||||
|
||||
/*
|
||||
* dtrace probes
|
||||
*/
|
||||
SDT_PROBE_DEFINE7(sdt, xen, clock, tsc__backward,
|
||||
"uint64_t"/*raw_systime_ns*/,
|
||||
"uint64_t"/*tsc_timestamp*/,
|
||||
"uint64_t"/*tsc_to_system_mul*/,
|
||||
"int"/*tsc_shift*/,
|
||||
"uint64_t"/*delta_ns*/,
|
||||
"uint64_t"/*tsc*/,
|
||||
"uint64_t"/*systime_ns*/);
|
||||
SDT_PROBE_DEFINE7(sdt, xen, clock, tsc__delta__negative,
|
||||
"uint64_t"/*raw_systime_ns*/,
|
||||
"uint64_t"/*tsc_timestamp*/,
|
||||
"uint64_t"/*tsc_to_system_mul*/,
|
||||
"int"/*tsc_shift*/,
|
||||
"uint64_t"/*delta_ns*/,
|
||||
"uint64_t"/*tsc*/,
|
||||
"uint64_t"/*systime_ns*/);
|
||||
SDT_PROBE_DEFINE7(sdt, xen, clock, systime__wraparound,
|
||||
"uint64_t"/*raw_systime_ns*/,
|
||||
"uint64_t"/*tsc_timestamp*/,
|
||||
"uint64_t"/*tsc_to_system_mul*/,
|
||||
"int"/*tsc_shift*/,
|
||||
"uint64_t"/*delta_ns*/,
|
||||
"uint64_t"/*tsc*/,
|
||||
"uint64_t"/*systime_ns*/);
|
||||
SDT_PROBE_DEFINE7(sdt, xen, clock, systime__backward,
|
||||
"uint64_t"/*raw_systime_ns*/,
|
||||
"uint64_t"/*tsc_timestamp*/,
|
||||
"uint64_t"/*tsc_to_system_mul*/,
|
||||
"int"/*tsc_shift*/,
|
||||
"uint64_t"/*delta_ns*/,
|
||||
"uint64_t"/*tsc*/,
|
||||
"uint64_t"/*systime_ns*/);
|
||||
|
||||
SDT_PROBE_DEFINE2(sdt, xen, hardclock, systime__backward,
|
||||
"uint64_t"/*last_systime_ns*/,
|
||||
"uint64_t"/*this_systime_ns*/);
|
||||
SDT_PROBE_DEFINE3(sdt, xen, hardclock, missed,
|
||||
"uint64_t"/*last_systime_ns*/,
|
||||
"uint64_t"/*this_systime_ns*/,
|
||||
"uint64_t"/*remaining_ns*/);
|
||||
|
||||
/*
|
||||
* xen timecounter:
|
||||
*
|
||||
|
|
@ -277,7 +322,11 @@ xen_vcputime_systime_ns(void)
|
|||
* Notify the console that the CPU's tsc appeared to
|
||||
* run behind Xen's idea of it, and pretend it hadn't.
|
||||
*/
|
||||
#if XEN_CLOCK_DEBUG /* XXX dtrace hook */
|
||||
SDT_PROBE7(sdt, xen, clock, tsc__backward,
|
||||
raw_systime_ns, tsc_timestamp,
|
||||
tsc_to_system_mul, tsc_shift, /*delta_ns*/0, tsc,
|
||||
/*systime_ns*/raw_systime_ns);
|
||||
#if XEN_CLOCK_DEBUG
|
||||
device_printf(ci->ci_dev, "xen cpu tsc %"PRIu64
|
||||
" ran backwards from timestamp %"PRIu64
|
||||
" by %"PRIu64"\n",
|
||||
|
|
@ -301,9 +350,13 @@ xen_vcputime_systime_ns(void)
|
|||
* This doesn't make sense but I include it out of paranoia.
|
||||
*/
|
||||
if (__predict_false((int64_t)delta_ns < 0)) {
|
||||
#if XEN_CLOCK_DEBUG /* XXX dtrace hook */
|
||||
device_printf(ci->ci_dev, "xen tsc delta in ns went negative: %"PRId64"\n",
|
||||
delta_ns);
|
||||
SDT_PROBE7(sdt, xen, clock, tsc__delta__negative,
|
||||
raw_systime_ns, tsc_timestamp,
|
||||
tsc_to_system_mul, tsc_shift, delta_ns, tsc,
|
||||
/*systime_ns*/raw_systime_ns);
|
||||
#if XEN_CLOCK_DEBUG
|
||||
device_printf(ci->ci_dev, "xen tsc delta in ns went negative:"
|
||||
" %"PRId64"\n", delta_ns);
|
||||
#endif
|
||||
ci->ci_xen_tsc_delta_negative_evcnt.ev_count++;
|
||||
delta_ns = 0;
|
||||
|
|
@ -322,7 +375,11 @@ xen_vcputime_systime_ns(void)
|
|||
* (2^64 ns is approximately half a millennium.)
|
||||
*/
|
||||
if (__predict_false(systime_ns < raw_systime_ns)) {
|
||||
#if XEN_CLOCK_DEBUG /* XXX dtrace hook */
|
||||
SDT_PROBE7(sdt, xen, clock, systime__wraparound,
|
||||
raw_systime_ns, tsc_timestamp,
|
||||
tsc_to_system_mul, tsc_shift, delta_ns, tsc,
|
||||
systime_ns);
|
||||
#if XEN_CLOCK_DEBUG
|
||||
printf("xen raw systime + tsc delta wrapped around:"
|
||||
" %"PRIu64" + %"PRIu64" = %"PRIu64"\n",
|
||||
raw_systime_ns, delta_ns, systime_ns);
|
||||
|
|
@ -336,7 +393,11 @@ xen_vcputime_systime_ns(void)
|
|||
* forward. This seems to happen pretty regularly under load.
|
||||
*/
|
||||
if (__predict_false(ci->ci_xen_last_systime_ns > systime_ns)) {
|
||||
#if XEN_CLOCK_DEBUG /* XXX dtrace hook */
|
||||
SDT_PROBE7(sdt, xen, clock, systime__backward,
|
||||
raw_systime_ns, tsc_timestamp,
|
||||
tsc_to_system_mul, tsc_shift, delta_ns, tsc,
|
||||
systime_ns);
|
||||
#if XEN_CLOCK_DEBUG
|
||||
printf("xen raw systime + tsc delta went backwards:"
|
||||
" %"PRIu64" > %"PRIu64"\n",
|
||||
ci->ci_xen_last_systime_ns, systime_ns);
|
||||
|
|
@ -692,8 +753,11 @@ again:
|
|||
last = ci->ci_xen_hardclock_systime_ns;
|
||||
now = xen_vcputime_systime_ns();
|
||||
if (now < last) {
|
||||
#if XEN_CLOCK_DEBUG /* XXX dtrace hook */
|
||||
device_printf(ci->ci_dev, "xen systime ran backwards in hardclock %"PRIu64"ns\n",
|
||||
SDT_PROBE2(sdt, xen, hardclock, systime__backward,
|
||||
last, now);
|
||||
#if XEN_CLOCK_DEBUG
|
||||
device_printf(ci->ci_dev, "xen systime ran backwards"
|
||||
" in hardclock %"PRIu64"ns\n",
|
||||
last - now);
|
||||
#endif
|
||||
ci->ci_xen_systime_backwards_hardclock_evcnt.ev_count++;
|
||||
|
|
@ -710,8 +774,11 @@ again:
|
|||
ci->ci_xen_hardclock_systime_ns += NS_PER_TICK;
|
||||
delta -= NS_PER_TICK;
|
||||
hardclock(frame);
|
||||
if (__predict_false(delta >= NS_PER_TICK))
|
||||
if (__predict_false(delta >= NS_PER_TICK)) {
|
||||
SDT_PROBE3(sdt, xen, hardclock, missed,
|
||||
last, now, delta);
|
||||
ci->ci_xen_missed_hardclock_evcnt.ev_count++;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
|
|||
Loading…
Reference in New Issue