On Thu, Jun 24, 2021 at 09:50:07PM -0500, Scott Cheloha wrote:
>
> [...]
>
> Stats for the clockintr subsystem are exposed via sysctl(2). If
> you're interested in providing them you can compile and run the
> program attached inline in my next mail. A snippet of the output from
> across a suspend/resume is especially useful.
>
> [...]
Here's the program I mentioned. It prints clockintr stats once per
second until you kill it (C-c works).
You will need to do `make includes` first, as the patch in the prior
mail added a new file to sys/dev and changed <sys/sysctl.h>. That or
you can do a full `make build`.
Assuming you put the inline file in clockintrstat.c, just build and
run:
$ cc -o clockintrstat clockintrstat.c
$ ./clockintrstat
Thanks,
-Scott
--
#include <sys/param.h>
#include <sys/sysctl.h>
#include <dev/clockintr.h>
#include <err.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
volatile sig_atomic_t uninterrupted = 1;
volatile sig_atomic_t need_header = 1;
void alrm(int);
void info(int);
void quit(int);
int
main(void)
{
struct clockintr_stat diff, new, old;
struct itimerval itv;
struct timespec elapsed, now, then;
uint64_t avg_lateness;
int mib[] = { CTL_KERN, KERN_CLOCKINTR_STATS };
sigset_t empty;
size_t len;
int first, rows;
memset(&diff, 0, sizeof(diff));
memset(&new, 0, sizeof(new));
memset(&old, 0, sizeof(old));
timespecclear(&now);
timespecclear(&then);
sigemptyset(&empty);
len = sizeof(old);
first = 1;
signal(SIGALRM, alrm);
signal(SIGINT, quit);
signal(SIGINFO, info);
itv.it_value.tv_sec = 1;
itv.it_value.tv_usec = 0;
itv.it_interval = itv.it_value;
if (setitimer(ITIMER_REAL, &itv, NULL) == -1)
err(1, "setitimer");
while (uninterrupted) {
if (need_header) {
need_header = 0;
printf("%20s %15s %7s %7s %7s %10s\n",
"uptime",
"elapsed",
"run",
"early",
"prompt",
"avg-late");
if (!first) {
sigsuspend(&empty);
continue;
}
}
old = new;
if (sysctl(mib, nitems(mib), &new, &len, NULL, 0) == -1)
err(1, "sysctl: KERN_CLOCKINTR_STATS");
then = now;
clock_gettime(CLOCK_BOOTTIME, &now);
if (first) {
first = 0;
sigsuspend(&empty);
continue;
}
timespecsub(&now, &then, &elapsed);
diff.cs_dispatch_early = new.cs_dispatch_early -
old.cs_dispatch_early;
diff.cs_dispatch_prompt = new.cs_dispatch_prompt -
old.cs_dispatch_prompt;
diff.cs_dispatch_lateness = new.cs_dispatch_lateness -
old.cs_dispatch_lateness;
diff.cs_events_run = new.cs_events_run - old.cs_events_run;
if (diff.cs_dispatch_prompt == 0)
avg_lateness = 0;
else
avg_lateness = diff.cs_dispatch_lateness /
diff.cs_dispatch_prompt;
printf("%10lld.%09ld %5lld.%09ld %7llu %7llu %7llu %10llu\n",
(long long)now.tv_sec,
now.tv_nsec,
(long long)elapsed.tv_sec,
elapsed.tv_nsec,
diff.cs_events_run,
diff.cs_dispatch_early,
diff.cs_dispatch_prompt,
avg_lateness);
sigsuspend(&empty);
}
return 0;
}
void
alrm(int signo)
{
}
void
info(int signo)
{
need_header = 1;
}
void
quit(int signo)
{
uninterrupted = 0;
}
