From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [119.145.14.64]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 017F61A01B0 for ; Tue, 16 Sep 2014 20:37:56 +1000 (EST) Message-ID: <541812EC.3000501@huawei.com> Date: Tue, 16 Sep 2014 18:37:32 +0800 From: Yijing Wang MIME-Version: 1.0 To: Lucas Stach Subject: Re: [PATCH v1 03/21] MSI: Remove the redundant irq_set_chip_data() References: <1409911806-10519-1-git-send-email-wangyijing@huawei.com> <1409911806-10519-4-git-send-email-wangyijing@huawei.com> <1410789648.3314.5.camel@pengutronix.de> <541792C0.9090303@huawei.com> <1410863349.2746.5.camel@pengutronix.de> In-Reply-To: <1410863349.2746.5.camel@pengutronix.de> Content-Type: text/plain; charset="UTF-8" Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, linux-pci@vger.kernel.org, Bharat.Bhushan@freescale.com, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Russell King , Joerg Roedel , x86@kernel.org, Sebastian Ott , xen-devel@lists.xenproject.org, arnab.basu@freescale.com, Arnd Bergmann , Konrad Rzeszutek Wilk , Chris Metcalf , Bjorn Helgaas , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Xinwei Hu , Tony Luck , Ralf Baechle , iommu@lists.linux-foundation.org, Wuyun , linuxppc-dev@lists.ozlabs.org, "David S. Miller" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , >>> arch_teardown_msi_irq() expects to find the msi_chip in the irq >>> chip_data field. As this means drivers don't have any reasonable other >>> possibility to stuff things into this field, I think it would make sense >>> to do the cleanup the other way around: keep the irq_set_chip_data >>> arch_setup_msi_irq() and rip it out of the individual drivers. >> >> Hi Lucas, thanks for your review and comments! >> irq_set_chip_data() should not be placed in MSI core functions, because other arch like x86, >> use irq_data->chip_data to stores irq_cfg. So how to set the chip_data is arch dependent. >> And this series is mainly to use MSI chip framework in all platforms. >> Currently, only ARM platform MSI drivers use the chip_data to store msi_chip, and the drivers call >> irq_set_chip_data() in their driver already. So I thought we should clean up it in MSI core code. >> > Okay I see your point, so the cleanup done this way is okay. > > But then this still introduces a problem: arch_teardown_msi_irq() > expects to find the msi_chip in the chip_data field, which is okay for > all ARM PCI host drivers, but not for other arch MSI chips. > > You fix this by completely removing arch_teardown_msi_irq() at the end > of the series, but this still has the potential to introduce issues for > other arches than ARM within the series. So this patch should include a > change to replace the line > > struct msi_chip *chip = irq_get_chip_data(irq); > > with something that doesn't rely on the msi_chip being in the irq > chip_data field. OK, I will update arch_teardown_msi_irq() in this patch, thanks! Thanks! Yijing. > > Regards, > Lucas > -- Thanks! Yijing