From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from szxga02-in.huawei.com ([119.145.14.65]:45906 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756515AbaDHJX0 (ORCPT ); Tue, 8 Apr 2014 05:23:26 -0400 Message-ID: <5343BFBC.1030208@huawei.com> Date: Tue, 8 Apr 2014 17:22:04 +0800 From: Yijing Wang MIME-Version: 1.0 To: Bjorn Helgaas CC: , "Rafael J. Wysocki" Subject: Re: [PATCH 1/2] PCI: rename pci_is_bridge() to pci_has_subordinate() References: <1394789889-11500-1-git-send-email-wangyijing@huawei.com> <20140404233157.GA15806@google.com> In-Reply-To: <20140404233157.GA15806@google.com> Content-Type: text/plain; charset="ISO-8859-1" Sender: linux-pci-owner@vger.kernel.org List-ID: >> >> - /* >> - * pci_is_bridge() is not suitable here, because pci_dev->subordinate >> - * is set only after acpi_pci_find_device() has been called for the >> - * given device. >> - */ > > This hunk shouldn't be here. My guess is that you intended to replace > the code below with the new pci_is_bridge() that you introduced in > patch [2/2]. That new pci_is_bridge() is never used, and it does the > same hdr_type test as the code below. But you apparently forgot to > change this code to use it? > >> check_children = pci_dev->hdr_type == PCI_HEADER_TYPE_BRIDGE >> || pci_dev->hdr_type == PCI_HEADER_TYPE_CARDBUS; >> /* Please ref to ACPI spec for the syntax of _ADR */ >> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c Hi Bjorn, I noticed the kernel compare (pci_dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) directly to identify bridge device. But the pci_is_brdge() helper function(which seems to do this) actually only check the device whether has subordinate bus. This maybe confuses people. So I think we should rename current pci_is_brdge(), and refactor a new pci_is_bridge() helper function. This can make code more readable, also there are a lot of codes using (pci_dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) directly compare. If you think this make sense, we can replace them by the new pci_is_bridge(). eg. in acpiphp: enable_device() ...... for (pass = 0; pass < 2; pass++) { list_for_each_entry(dev, &bus->devices, bus_list) { if (PCI_SLOT(dev->devfn) != slot->device) continue; if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE || dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) { max = pci_scan_bridge(bus, dev, max, pass); if (pass && dev->subordinate) pci_bus_size_bridges(dev->subordinate); } } } ...... and in PCI core code pci_rescan_bus() ....... down_read(&pci_bus_sem); list_for_each_entry(dev, &bus->devices, bus_list) if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE || dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) if (dev->subordinate) __pci_bus_size_bridges(dev->subordinate, &add_list); up_read(&pci_bus_sem); .......... Thanks! Yijing. >> index 25f0bc6..019dcb2 100644 >> --- a/drivers/pci/pci-driver.c >> +++ b/drivers/pci/pci-driver.c >> @@ -580,14 +580,14 @@ static void pci_pm_default_resume(struct pci_dev *pci_dev) >> { >> pci_fixup_device(pci_fixup_resume, pci_dev); >> >> - if (!pci_is_bridge(pci_dev)) >> + if (!pci_has_subordinate(pci_dev)) > > The rest of this is a simple rename and looks fine to me. > >> pci_enable_wake(pci_dev, PCI_D0, false); >> } >> >> static void pci_pm_default_suspend(struct pci_dev *pci_dev) >> { >> /* Disable non-bridge devices without PM support */ >> - if (!pci_is_bridge(pci_dev)) >> + if (!pci_has_subordinate(pci_dev)) >> pci_disable_enabled_device(pci_dev); >> } >> >> @@ -711,7 +711,7 @@ static int pci_pm_suspend_noirq(struct device *dev) >> >> if (!pci_dev->state_saved) { >> pci_save_state(pci_dev); >> - if (!pci_is_bridge(pci_dev)) >> + if (!pci_has_subordinate(pci_dev)) >> pci_prepare_to_sleep(pci_dev); >> } >> >> @@ -954,7 +954,7 @@ static int pci_pm_poweroff_noirq(struct device *dev) >> return error; >> } >> >> - if (!pci_dev->state_saved && !pci_is_bridge(pci_dev)) >> + if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev)) >> pci_prepare_to_sleep(pci_dev); >> >> /* >> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h >> index 4df38df..a3b9cc1 100644 >> --- a/drivers/pci/pci.h >> +++ b/drivers/pci/pci.h >> @@ -79,7 +79,7 @@ static inline void pci_wakeup_event(struct pci_dev *dev) >> pm_wakeup_event(&dev->dev, 100); >> } >> >> -static inline bool pci_is_bridge(struct pci_dev *pci_dev) >> +static inline bool pci_has_subordinate(struct pci_dev *pci_dev) >> { >> return !!(pci_dev->subordinate); >> } >> -- >> 1.7.1 >> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- Thanks! Yijing