hi, please bug me in a couple weeks. still moving house, etc.
-a On 16 February 2016 at 02:30, Slawa Olhovchenkov <s...@zxy.spb.ru> wrote: > On Tue, Feb 16, 2016 at 11:23:20AM +0100, Giuseppe Lettieri wrote: > >> I am sorry, I did not participate to the implementation of kqueue >> support and I am not able to comment. Luigi and Adrian should know, however. > > Thanks! > >> Cheers, >> Giuseppe >> >> Il 15/02/2016 22:44, Slawa Olhovchenkov ha scritto: >> > On Mon, Feb 15, 2016 at 05:02:36PM +0100, Giuseppe Lettieri wrote: >> > >> >> Il 15/02/2016 16:13, Slawa Olhovchenkov ha scritto: >> >>> On Mon, Feb 15, 2016 at 04:10:30PM +0100, Giuseppe Lettieri wrote: >> >>> >> >>>> Hi Slawa, >> >>>> >> >>>> I think WITNESS is seeing a false positive, since those two are always >> >>>> different mutexes. >> >>>> >> >>>> The actual deadlock you experience should be caused by something else. I >> >>> >> >>> Are you sure? When deadlock occur I am see threads waiting on nm_kn_lock. >> >> >> >> The deadlock I mentioned still involves nm_kn_locks, sorry if I was not >> >> clear about that. I am just saying that we never try to take the same >> >> lock that we already holding. >> >> >> >> Nonetheless, there are indeed problems in the path that WITNESS has >> >> seen. The problem is that pipes have to notify the other end while >> >> called by kevent. kevent holds the nm_kn_lock on the TX src ring and the >> >> notification takes the nm_kn_lock on the RX dst ring. >> > >> > Can you comment other issuses? Is this by design or is this bug? >> > >> > - with kevent sync for transmiting need first register >> > EVFILT_WRITE/EV_DISABLE and after every write >> > EVFILT_WRITE/EV_DISPATCH >> > >> > - with kevent sync all opening /dev/netmap and registering need do >> > from same thread as kevent using for sinc (unless no RX/TX). >> > >> > >> >> >> -- >> Dr. Ing. Giuseppe Lettieri >> Dipartimento di Ingegneria della Informazione >> Universita' di Pisa >> Largo Lucio Lazzarino 1, 56122 Pisa - Italy >> Ph. : (+39) 050-2217.649 (direct) .599 (switch) >> Fax : (+39) 050-2217.600 >> e-mail: g.letti...@iet.unipi.it _______________________________________________ freebsd-stable@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
