This is the mail archive of the
systemtap@sourceware.org
mailing list for the systemtap project.
Re: pre-compiled modules
- From: Martin Hunt <hunt at redhat dot com>
- To: "Frank Ch. Eigler" <fche at redhat dot com>
- Cc: David Smith <dsmith at redhat dot com>, systemtap at sources dot redhat dot com
- Date: Mon, 19 Jun 2006 10:22:57 -0700
- Subject: Re: pre-compiled modules
- Organization: Red Hat Inc.
- References: <1150298740.16471.33.camel@dhcp-2.hsv.redhat.com> <20060619164051.GP30867@redhat.com>
On Mon, 2006-06-19 at 12:40 -0400, Frank Ch. Eigler wrote:
> Hi -
>
> dsmith wrote:
>
> > I've been looking at pre-compiled modules, and in general they should
> > work. I do have a few questions:
> >
> > 1) One thing I've been worried about is differing options between
> > compile time and run time. I believe that most of them should be OK,
> > with the exception of the '-b' relayfs option. If it was specified at
> > compile time and not at run time (or vice versa), I'm not sure what will
> > happen (since that flag appears to change behavior both at compile time
> > and run time).
> >
> > Got any ideas here on how to prevent this?
I designed stpd from the beginning to get all its parameters from the
module it is loading. Some, like buffer size, can be overridden at the
command line. However you cannot force the transport; it will use
whatever the module uses.
> One possibility would be to remove the run-time meaning of -b: don't
> pass it to stpd any more.
Stpd doesn't get "-b". It does recognize "-r", which is a hack. Without
it, stpd runs "stp_check" which used to do all kinds of things including
compiling and loading relayfs if necessary. Now it just
mounts /mnt/relay.
Anyway, "-r" can probably be safely eliminated. I will make a note to
try it ASAP.
> Perhaps the value could flow by/within the
> module to the runtime to stpd at run time.
It does.
> Perhaps the
> stp_check/mount check could be deferred until late in the module
> initialization sequence.
Probably. That's what I plan to try.
Martin