Hi,
I'm trying to understand what exactly is going on here...
On Thu, Feb 12, 2015 at 08:58:19AM -0500, Prarit Bhargava wrote:
> The test did the following in userspace:
>
> tx.modes = ADJ_STATUS;
> tx.status = STA_INS;
>
> /* send leap second request */
> ret = adjtimex(&tx);
>
> /* Check adjtimex output every half second */
> now = tx.time.tv_sec;
> while (now < next_leap+2) {
> char buf[26];
> ret = adjtimex(&tx);
>
> ctime_r(&tx.time.tv_sec, buf);
> buf[strlen(buf)-1] = 0; /*remove trailing\n */
>
> printf("%s + %6ld us\t%s\n",
> buf,
> tx.time.tv_usec,
> time_state_str(ret));
> now = tx.time.tv_sec;
> /* Sleep for another half second */
> ts.tv_sec = 0;
> ts.tv_nsec = NSEC_PER_SEC/2;
> clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, NULL);
> }
>
> After some investigation it was noted that the test contained a small error:
> the test does not reinitialize tx.status and reissues the STA_INS every
> 1/2 second.
Prarit, can you explain who sets the STA_PLL flag, so that
process_adj_status() detects a STA_PLL->!STA_PLL transition and
goes to the branch that sets time_state = TIME_OK?
Is that ntpd running in parallel with your test program? If that
is the case, you would eventually end up oscilating between the
the TIME_INS and TIME_OK states anyway, even with your patch.
ntpd will clear the STA_INS flag after midnight, the state
machine will transition from TIME_WAIT to TIME_OK and your test
program will set STA_INS again (fighting with ntpd which will
clear the flag from time to time) ... right?
Thanks,
--
Jiri Bohac <jbo...@suse.cz>
SUSE Labs, SUSE CZ
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