On Fri, Dec 2, 2016 at 1:49 AM, John Baldwin <j...@freebsd.org> wrote: > On Thursday, December 01, 2016 01:53:29 PM Sepherosa Ziehau wrote: >> On Wed, Nov 30, 2016 at 9:59 AM, Sepherosa Ziehau <sepher...@gmail.com> >> wrote: >> >>> After fdc is disabled and hyperv/storvsc is fixed, it seems to boot >> >>> fine, except a long delay (28~30seconds) here: >> >>> .... >> >>> Timecounters tick every 1.000 msec >> >>> ----- >> >>> 28 ~ 30 seconds delay >> >>> ----- >> >>> vlan: initialized, using hash tables with chaining >> >>> .... >> >>> >> >>> I have the bootverbose dmesg here: >> >>> https://people.freebsd.org/~sephe/dmesg_earlyap.txt >> >>> >> >>> I booted 10 times, only one boot does not suffer this 30 seconds >> >>> delay. It sounds like some races to me. Any hints? >> >> >> >> It is likely a race as we start running things sooner now, yes. Can you >> >> break into DDB during the hang and see what thread0 is waiting on? If >> >> it is in the interrupt hooks you can use 'show conifhk' in DDB to see the >> >> list of pending interrupt hooks. That provides a list of candidate >> >> drivers >> >> to inspect (e.g. stack traces of relevant kthreads) for what is actually >> >> waiting (and what it is waiting on) >> > >> > Just tried, but I failed to break into DDB during the 30 seconds >> > delay. DDB was entered after the 30 seconds delay, though I press the >> > break key when the delay started. >> >> I tried add VERBOSE_SYSINIT option in order to get a rough location of >> this delay, but the system boots just fine w/ VERBOSE_SYSINIT option, >> sigh. > > You could add KTR_PROC tracing and use 'show ktr' in DDB when you break in > after the > 30 second delay to see what it was doing during the delay perhaps?
I have narrowed it down by patching the VERBOSE_SYSINIT: the kthread_start(&deadlkres_kd) introduces the 30 seconds delay, i.e. SYSINIT(deadlkres, SI_SUB_CLOCKS, SI_ORDER_ANY, kthread_start, &deadlkres_kd) blocks for 30 seconds. Thanks, sephe -- Tomorrow Will Never Die _______________________________________________ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
