Date: Wed, 13 Jun 2001 18:11:20 +0100 (BST) From: Doug Rabson <dfr@nlsystems.com> To: John Baldwin <jhb@FreeBSD.org> Cc: Matthew Jacob <mjacob@feral.com>, <freebsd-alpha@FreeBSD.org>, <wilko@FreeBSD.org>, Andrew Gallatin <gallatin@cs.duke.edu> Subject: Re: followup on 8 way SMP pani Message-ID: <Pine.BSF.4.33.0106131809030.24151-100000@herring.nlsystems.com> In-Reply-To: <XFMail.010613095649.jhb@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, 13 Jun 2001, John Baldwin wrote:
>
> On 13-Jun-01 Matthew Jacob wrote:
> >
> >
> > What I needed to fix for turbolaser is to clear the timer interrupt for all
> > CPUs but the primary CPU- this is the TLINTRMASK{0,1} registers. But, stupid
> > me, I upgraded my source first.
>
> Ok, then we will need to change how platform.clockintr works slightly. (It
> will need to do more) and then forward_*clock in sys/i386/i386/mp_machdep.c
> will need to be moved to sys/kern/subr_smp.c, and a few tweaks need to made to
> smp_handle_ipis() in alpha/alpha/mp_machdep.c, and the tlsb will need a custom
> platform.clockintr that handles clock interrupts the way x86 does by IPI'ing
> all other processses to go handle clock interrupts. Hmmm. Actually.
>
> You shouldn't even have to do this. SMP doesn't need the i8254 timecounter on
> the alpha actually, because we make it so that only the boot CPU actually
> messes with the timecounters, so a non-i8254 timecounter should work fine on
> SMP systems just fine right now. The reason I think dfr used hte i8254 before
> was that in pre-SMPng we did need to handle clock interrupts on whatever CPU
> owned the kernel lock, but now we don't have that same restriction.
Are you saying that no code in the kernel calls nanotime(9) unless its
running on the boot cpu? If so, then we can use the alpha timecounter. If
not, then we need to find a decent clock somewhere in the tlaser hardware.
I'd loke to do the same for rawhide too since the i8254 really sucks.
--
Doug Rabson Mail: dfr@nlsystems.com
Phone: +44 20 8348 6160
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-alpha" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.33.0106131809030.24151-100000>