Date: Fri, 27 Sep 2019 23:37:43 +0300 From: Oleksandr Rybalko <ray@ddteam.net> To: mike tancsa <mike@sentex.net> Cc: Warner Losh <imp@bsdimp.com>, freebsd-embedded <freebsd-embedded@freebsd.org> Subject: Re: watchdogd stat location Message-ID: <CAJ1Oi8HWrEHUTwSq%2B0QTGVCUdne9SEwsAOBOD8eJtZHmv-76_Q@mail.gmail.com> In-Reply-To: <fcdd9659-d7e4-c554-b501-6b8cd178f6d7@sentex.net> References: <5eba25eb-9ba4-0c93-27c8-e834491298ad@sentex.net> <CANCZdfp6bym5b6eFXFH0MxjYsAX%2B1Bi9fGXgp7sFM206zmsveQ@mail.gmail.com> <CAJ1Oi8FsG=nEBXdd0CS3U2zZSgh=SMcBO0ieY-KT5b1iDVFmJg@mail.gmail.com> <83831ae6-9275-4f0c-a23d-c9cca3dc28f4@sentex.net> <CANCZdfrRh7Ssf9vSSJ4Hopec1q7abLi9AdUqoPqZm4hPok6QUQ@mail.gmail.com> <fcdd9659-d7e4-c554-b501-6b8cd178f6d7@sentex.net>
next in thread | previous in thread | raw e-mail | index | archive | help
/sbin and /usr may fail in many case.
Maybe readdir, then rand stat?
=D0=BF=D1=82, 27 =D0=B2=D0=B5=D1=80. 2019 =D0=BE 23:30 mike tancsa <mike@se=
ntex.net> =D0=BF=D0=B8=D1=88=D0=B5:
> On 9/27/2019 3:53 PM, Warner Losh wrote:
> > >
> >
> > I am all for that too. Just something other than /etc or /var
> > which are
> > often mounted on ramdisk.
> >
> >
> > I think that / is too special to cause disk IO to ever happen. Other
> > dirs will sometimes not be in the cache.... The notion here, perhaps
> > bogus, is that we want to check the root FS is sane. The stat(2) is a
> > cheap way to do this that will eventually fail if / goes wonky enough.
> > It's weak.
> >
> >
> Would something like this buy any extra sanity ? or not worth it. I
> guess fancier checks belong in a passed program
>
>
> # diff -u watchdogd.c.orig watchdogd.c
> --- watchdogd.c.orig 2019-09-27 16:27:14.456973000 -0400
> +++ watchdogd.c 2019-09-27 16:27:18.904885000 -0400
> @@ -364,9 +364,23 @@
>
> if (test_cmd !=3D NULL)
> failed =3D system(test_cmd);
> - else
> - failed =3D stat("/etc", &sb);
> -
> + else {
> +
> + srand(time(NULL));
> + switch(rand() % 4) {
> + case 0:
> + failed =3D stat("/", &sb);
> + break;
> + case 1:
> + failed =3D stat("/bin", &sb);
> + break;
> + case 2:
> + failed =3D stat("/sbin", &sb);
> + break;
> + default:
> + failed =3D stat("/usr", &sb);
> + }
> + }
> error =3D watchdog_getuptime(&ts_end);
> if (error) {
> end_program =3D 1;
>
>
>
>
>
--=20
WBW
-------
Rybalko Aleksandr <ray@ddteam.net>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAJ1Oi8HWrEHUTwSq%2B0QTGVCUdne9SEwsAOBOD8eJtZHmv-76_Q>