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Date: Tue, 21 Mar 1995 15:29:41 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199503210529.PAA04875@godzilla.zeta.org.au>
To: current@FreeBSD.org, se@MI.Uni-Koeln.DE
Subject: Re: Sharing interrupts with PCI devices?
Sender: current-owner@FreeBSD.org
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>This results in low overhead operation 
>in the non shared case, and in interrupts
>masked for as short a period of time as
>possible in the shared case.

>*** *** *** *** *** *** *** *** *** *** ***

>I will apply the PCI SHARED INTERRUPT patch
>tomorrow. All PCI device drivers will have 
>been checked to conform to the return value 
>convention described above !

This results in a higher overhead operation
in the non-shared case :-].  What about
generic drivers like isa/bt742a.c?  Does
the new requirement give higher overhead
in the non-shared ISA (VLB) case?

The overheads are relatively _very_ small for
devices that transfer large blocks so I'm not
worried about the overheads for bt742a.

Bruce