From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH] Netpoll support for Sibyte MAC Date: Tue, 20 Mar 2007 17:34:01 +0300 Message-ID: <45FFF0D9.4020905@ru.mvista.com> References: <20070319224311.GA10176@plexity.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, ralf@linux-mips.org, jeff@garzik.org, linux-mips@linux-mips.org, Manish Lachwani To: dsaxena@plexity.net Return-path: Received: from h155.mvista.com ([63.81.120.155]:58369 "EHLO imap.sh.mvista.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S933534AbXCTOd1 (ORCPT ); Tue, 20 Mar 2007 10:33:27 -0400 In-Reply-To: <20070319224311.GA10176@plexity.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Hello. Deepak Saxena wrote: > NETPOLL support for Sibyte MAC > Index: linux-2.6.18/drivers/net/sb1250-mac.c > =================================================================== > --- linux-2.6.18.orig/drivers/net/sb1250-mac.c > +++ linux-2.6.18/drivers/net/sb1250-mac.c > @@ -1128,6 +1128,26 @@ static void sbdma_fillring(sbmacdma_t *d > } > } > > +#ifdef CONFIG_NET_POLL_CONTROLLER > +static void sbmac_netpoll(struct net_device *netdev) > +{ > + struct sbmac_softc *sc = netdev_priv(netdev); > + int irq = sc->sbm_dev->irq; > + > + __raw_writeq(0, sc->sbm_imr); > + Thinking about it again, I'm not sure that blindly writing to the chip reg. to mask interrupts is SMP-safe enough (versus disable_irq()). I know why it was done this way -- to quell the BUG emitted in the realtime mode on SMP -- because of scheduling with disabled interrupts in synchoronize_irq(), but after having spent much time on netpoll, I'm no longer sure that anything but disable_irq() is safe enough for SMP since -- otherwise there's no warranty that sbmac_intr() is not running on another CPU... > + sbmac_intr(irq, netdev, NULL); > + > +#ifdef CONFIG_SBMAC_COALESCE > + __raw_writeq(((M_MAC_INT_EOP_COUNT | M_MAC_INT_EOP_TIMER) << S_MAC_TX_CH0) | > + ((M_MAC_INT_EOP_COUNT | M_MAC_INT_EOP_TIMER) << S_MAC_RX_CH0), > + sc->sbm_imr); > +#else > + __raw_writeq((M_MAC_INT_CHANNEL << S_MAC_TX_CH0) | > + (M_MAC_INT_CHANNEL << S_MAC_RX_CH0), sc->sbm_imr); > +#endif > +} > +#endif WBR, Sergei