From owner-freebsd-net  Wed Dec  5 19: 0:36 2001
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Date: Wed, 5 Dec 2001 19:00:17 -0800
From: Luigi Rizzo <luigi@FreeBSD.ORG>
To: misho <misho@interbgc.com>
Cc: net@FreeBSD.ORG
Subject: Re: HEADS-UP: net polling code now in STABLE.
Message-ID: <20011205190017.A68166@iguana.aciri.org>
References: <20011203221742.A50473@iguana.aciri.org> <3C0CBE2D.1050505@gmx.net> <20011204175148.B58039@iguana.aciri.org> <3C0E3856.2000507@gmx.net> <20011205082203.A63639@iguana.aciri.org> <000c01c17e00$ce170740$eee209d9@cablebg.net>
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On Thu, Dec 06, 2001 at 04:50:46AM +0200, misho wrote:
> Hi Luigi,
> 
> I found this bug several days ago, but I don;t have free time to send you
> simple patch.
> In my opinion it;s better to disable interrupts in xxx_intr() code when
> device is in polling mode.
> Something like this:

I have committed a proper fix yesterday.

The code you propose is a safety belt to mask bugs, but *_intr()
could still be called because other devices are sharing the interrupt
line (this is actually very common when you have many interfaces).

As a matter of fact, calling *_stop() or writing to I/O registers
when you get some unwanted interrupts is a bad thing because the
operations involved can be very time consuming.

	cheers
	luigi

> /*
>  * Process interface interrupts.
>  */
> static void
> fxp_intr(void *xsc)
> {
>  struct fxp_softc *sc = xsc;
>  u_int8_t statack;
> 
> #ifdef DEVICE_POLLING
>  struct ifnet *ifp = &sc->sc_if;
> 
>  if (ifp->if_ipending & IFF_POLLING) {
>       /* this shouldn't happen, we are in polling mode
>        *     disable interrupts
>        */
>       CSR_WRITE_1(sc, FXP_CSR_SCB_INTRCNTL, FXP_SCB_INTR_DISABLE);
>       return;
> }
>  if (ether_poll_register(fxp_poll, ifp)) {

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