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Date: Sun, 20 Jul 1997 14:03:37 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199707200403.OAA23396@godzilla.zeta.org.au>
To: current@FreeBSD.ORG, smp@csn.net
Subject: Re: INT priorities
Cc: smp@FreeBSD.ORG
Sender: owner-freebsd-smp@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk

>I am currently struggling with INT code in the SMP kernel.  To solve
>the "problem of the day", I think I need to make a leap and re-arrange
>the hw INTs to different APIC priority levels.  For the first stab this
>means 'constant' INTs like the 8254, RTC and possibly keyboard.  I have 7 or 8
>prio levels to play with.  Any suggestions where these should end up relative
>to the rest of the INTs?

The (non-SMP) kernel doesn't really care.  It uses spl priorities
for essentially everything except fast interrupt handlers.  For fast
interrupt handlers, the priorities only matter for interrupts that
arrive concurrently.

Bruce