Date: Mon, 11 Apr 2016 15:16:22 -0700 From: Jack Vogel <jfvogel@gmail.com> To: Matt Joras <matt.joras@gmail.com> Cc: "K. Macy" <kmacy@freebsd.org>, FreeBSD Net <freebsd-net@freebsd.org> Subject: Re: Question on sysctl tree handling Message-ID: <CAFOYbcnTnJEsLydmoxxPvuETGCD7fpjrnmFQ5R9XaeP_5nyjgw@mail.gmail.com> In-Reply-To: <CADdTf%2BjD4ncCNjL67BgTH_SUtuw%2BDg4J0ttEVHOWTjvTuv1dNQ@mail.gmail.com> References: <CAFOYbcnufB18%2B94RYW2e7cE_uaEOvGW=pNgOVxyPdhgZoksSyg@mail.gmail.com> <CAFOYbcmgEt7jYvDSxCJ-ZPcdN8n6n2GdSGXGzMpHaQ2szskwmg@mail.gmail.com> <CAHM0Q_NNAb6K499p-mhThOdW4u68VywRAsJCwd2_HL_46D8g7w@mail.gmail.com> <CADdTf%2BjD4ncCNjL67BgTH_SUtuw%2BDg4J0ttEVHOWTjvTuv1dNQ@mail.gmail.com>
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Hmmm, after so many years of unloading and reloading drivers, it just seemed like such a convenience :) But, instability isn't fun either, I've looked at bxe a little, such a monstrous driver :) I'll give it some thought, and maybe discuss it with David. Thanks. Cheers, Jack On Mon, Apr 11, 2016 at 3:09 PM, Matt Joras <matt.joras@gmail.com> wrote: > Expanding on what mmacy said... I don't think the benefits of "easy > reconfiguration" are worth the headaches you're going to potentially > run into in production. > > bxe(4) used to do this, and it caused us a lot of problems (i.e. panics) > at $DAY_JOB. For example, if a lagg was on top of bxe and then you > downed bxe you could very easily hit a use-after-free since bxe free'd > its rings while if_lagg is trying to transmit a packet. > > Matt Joras > > On Mon, Apr 11, 2016 at 2:03 PM, K. Macy <kmacy@freebsd.org> wrote: > > You do understand that init needs to be run every time interface > > settings are changed (TSO / PROMISC / CSUM/ etc)? Reallocating queues > > and interrupts every time is fragile (long running systems can run low > > on contiguous memory) and, in the common case that you're not actually > > changing the number, gratuitous. > > > > Cheers. > > -M > > > > On Fri, Apr 8, 2016 at 2:56 PM, Jack Vogel <jfvogel@gmail.com> wrote: > >> LOL, why does it seem that as soon as I ask the answer hits me in the > nose > >> :) > >> > >> I found the sysctl_ctx_free call, sorry for the noise.... > >> > >> Jack > >> > >> > >> On Fri, Apr 8, 2016 at 2:51 PM, Jack Vogel <jfvogel@gmail.com> wrote: > >> > >>> > >>> I have a driver design where the queue/ring/irq layout is done in init > >>> rather > >>> than in attach, allowing easy reconfiguration. What I'm not sure about > is > >>> how to handle the sysctl tree during a reinit, I don't see a procedure > to > >>> free up things so I can restructure :( > >>> > >>> Am I missing something, any pointers or suggestions appreciated. > >>> > >>> Thanks, > >>> > >>> Jack > >>> > >>> > >> _______________________________________________ > >> freebsd-net@freebsd.org mailing list > >> https://lists.freebsd.org/mailman/listinfo/freebsd-net > >> To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" > > _______________________________________________ > > freebsd-net@freebsd.org mailing list > > https://lists.freebsd.org/mailman/listinfo/freebsd-net > > To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" >
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