Date: Fri, 19 Nov 2010 16:46:17 -0500 From: Jung-uk Kim <jkim@FreeBSD.org> To: Attilio Rao <attilio@freebsd.org> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org, John Baldwin <jhb@freebsd.org> Subject: Re: svn commit: r215544 - head/sys/kern Message-ID: <201011191646.20048.jkim@FreeBSD.org> In-Reply-To: <AANLkTimzP7hNYFqsYgFW4Vzuj-cOWO%2Bq9nU4vFMTJ3R=@mail.gmail.com> References: <201011191943.oAJJhv3i087205@svn.freebsd.org> <201011191621.25520.jhb@freebsd.org> <AANLkTimzP7hNYFqsYgFW4Vzuj-cOWO%2Bq9nU4vFMTJ3R=@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Friday 19 November 2010 04:31 pm, Attilio Rao wrote: > 2010/11/19 John Baldwin <jhb@freebsd.org>: > > On Friday, November 19, 2010 4:09:28 pm Jung-uk Kim wrote: > >> On Friday 19 November 2010 02:43 pm, Attilio Rao wrote: > >> > Author: attilio > >> > Date: Fri Nov 19 19:43:56 2010 > >> > New Revision: 215544 > >> > URL: http://svn.freebsd.org/changeset/base/215544 > >> > > >> > Log: > >> > Scan the list in reverse order for the shutdown handlers of > >> > loaded modules. This way, when there is a dependency between > >> > two modules, the handler of the latter probed runs first. > >> > > >> > This is a similar approach as the modules are unloaded in > >> > the same linkerfile. > >> > > >> > Sponsored by: Sandvine Incorporated > >> > Submitted by: Nima Misaghian <nmisaghian at sandvine dot > >> > com> MFC after: 1 week > >> > >> Hmm... It is not directly related but I was thinking about > >> doing similar things for sys/kern/subr_bus.c. What do you think > >> about the attached patch? > > > > Hmm, the patches for suspend and resume that I had for this took > > the opposite order, they did suspend in forward order, but resume > > in backwards order. Like so: > > > > --- //depot/vendor/freebsd/src/sys/kern/subr_bus.c > > 2010-11-17 22:30:24.000000000 0000 +++ > > //depot/user/jhb/acpipci/kern/subr_bus.c 2010-11-19 > > 17:19:02.000000000 00 @@ -3426,9 +3429,9 @@ > > TAILQ_FOREACH(child, &dev->children, link) { > > error = DEVICE_SUSPEND(child); > > if (error) { > > - for (child2 = > > TAILQ_FIRST(&dev->children); - child2 > > && child2 != child; > > - child2 = TAILQ_NEXT(child2, link)) > > + for (child2 = TAILQ_PREV(child, > > device_list, link); + child2 != NULL; > > + child2 = TAILQ_PREV(child2, > > device_list, link)) DEVICE_RESUME(child2); > > return (error); > > } > > @@ -3447,7 +3450,7 @@ > > { > > device_t child; > > > > - TAILQ_FOREACH(child, &dev->children, link) { > > + TAILQ_FOREACH_REVERSE(child, &dev->children, device_list, > > link) { DEVICE_RESUME(child); > > /* if resume fails, there's nothing we can > > usefully do... */ } > > > > (Likely mangled whitespace.) > > > > I couldn't convince myself which order was "more" correct for > > suspend and resume. > > Considering loading in starting point, I think suspend should go in > reverse logic and resume in the same module load logic. > So that dependent modules are suspended first and resumed after. > Don't you agree? That's exactly what I was thinking. :-) Jung-uk Kim
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201011191646.20048.jkim>