From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH v6 1/4] PCI: Introduce pci_dev_for_each_resource() Date: Thu, 23 Mar 2023 16:30:01 +0200 Message-ID: References: <20230320131633.61680-2-andriy.shevchenko@linux.intel.com> <20230322192804.GA2485349@bhelgaas> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679581820; x=1711117820; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=yycxH1AeGogQsiHx6KGAN/nQ6jWFX888/jtMkSYZfjo=; b=dEv1rEs9jwcv0QKQ5fGqOQOtSuoN4whzoRgOjeCKSDY3D6oZNBkeEt13 1025Deb/A24ZhYf5mk2euVhtstLL0HLDIezQMK5oWWJafOwYZrNLZm30b 3Jhd7a0QYfxsqDctZuDh+V0J0mNNx7nGWAcFmxZRljitCCCFz3QtTEOuD zsBaRQNfNBkr0CptfGUDRVFDrI63KYSCNF8HiNMLOkEbeOWuN1fD9WJDr b9UXIP0ZIPBgcY1pnh9/V7ygiHwGQuhthDdha8AmQGVMoLt4MQLxCDuJk TSSQNEaWjr3AfUs9Myhm9Lg2F7kpDXJVZGQaXdTh5ummbFiCiHNYJaxa1 w==; Content-Disposition: inline In-Reply-To: <20230322192804.GA2485349@bhelgaas> List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Bjorn Helgaas Cc: =?iso-8859-1?Q?Micka=EBl_Sala=FCn?= , Mika Westerberg , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Michael Ellerman , Randy Dunlap , Arnd Bergmann , Niklas Schnelle , "Rafael J. Wysocki" , Pali =?iso-8859-1?Q?Roh=E1r?= , "Maciej W. Rozycki" , Juergen Gross , Dominik Brodowski , linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-pci@vger.kernel.org On Wed, Mar 22, 2023 at 02:28:04PM -0500, Bjorn Helgaas wrote: > On Mon, Mar 20, 2023 at 03:16:30PM +0200, Andy Shevchenko wrote: ... > > + pci_dev_for_each_resource_p(dev, r) { > > /* zap the 2nd function of the winbond chip */ > > - if (dev->resource[i].flags & IORESOURCE_IO > > - && dev->bus->number == 0 && dev->devfn == 0x81) > > - dev->resource[i].flags &= ~IORESOURCE_IO; > > - if (dev->resource[i].start == 0 && dev->resource[i].end) { > > - dev->resource[i].flags = 0; > > - dev->resource[i].end = 0; > > + if (dev->bus->number == 0 && dev->devfn == 0x81 && > > + r->flags & IORESOURCE_IO) > > This is a nice literal conversion, but it's kind of lame to test > bus->number and devfn *inside* the loop here, since they can't change > inside the loop. Hmm... why are you asking me, even if I may agree on that? It's in the original code and out of scope of this series. > > + r->flags &= ~IORESOURCE_IO; > > + if (r->start == 0 && r->end) { > > + r->flags = 0; > > + r->end = 0; > > } > > } ... > > #define pci_resource_len(dev,bar) \ > > ((pci_resource_end((dev), (bar)) == 0) ? 0 : \ > > \ > > - (pci_resource_end((dev), (bar)) - \ > > - pci_resource_start((dev), (bar)) + 1)) > > + resource_size(pci_resource_n((dev), (bar)))) > > I like this change, but it's unrelated to pci_dev_for_each_resource() > and unmentioned in the commit log. And as you rightfully noticed this either. I can split it to a separate one. ... > > +#define __pci_dev_for_each_resource(dev, res, __i, vartype) \ > > + for (vartype __i = 0; \ > > + res = pci_resource_n(dev, __i), __i < PCI_NUM_RESOURCES; \ > > + __i++) > > + > > +#define pci_dev_for_each_resource(dev, res, i) \ > > + __pci_dev_for_each_resource(dev, res, i, ) > > + > > +#define pci_dev_for_each_resource_p(dev, res) \ > > + __pci_dev_for_each_resource(dev, res, __i, unsigned int) > > This series converts many cases to drop the iterator variable ("i"), > which is fantastic. > > Several of the remaining places need the iterator variable only to > call pci_claim_resource(), which could be converted to take a "struct > resource *" directly without much trouble. > > We don't have to do that pci_claim_resource() conversion now, Exactly, it's definitely should be separate change. > but > since we're converging on the "(dev, res)" style, I think we should > reverse the names so we have something like: > > pci_dev_for_each_resource(dev, res) > pci_dev_for_each_resource_idx(dev, res, i) Wouldn't it be more churn, including pci_bus_for_each_resource() correction? ... > Not sure __pci_dev_for_each_resource() is worthwhile since it only > avoids repeating that single "for" statement, and passing in "vartype" > (sometimes empty to implicitly avoid the declaration) is a little > complicated to read. I think it'd be easier to read like this: No objections here. > #define pci_dev_for_each_resource(dev, res) \ > for (unsigned int __i = 0; \ > res = pci_resource_n(dev, __i), __i < PCI_NUM_RESOURCES; \ > __i++) > > #define pci_dev_for_each_resource_idx(dev, res, idx) \ > for (idx = 0; \ > res = pci_resource_n(dev, idx), idx < PCI_NUM_RESOURCES; \ > idx++) -- With Best Regards, Andy Shevchenko