Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753777AbbBZBc4 (ORCPT ); Wed, 25 Feb 2015 20:32:56 -0500 Received: from [119.145.14.64] ([119.145.14.64]:23614 "EHLO szxga01-in.huawei.com" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753563AbbBZBck (ORCPT ); Wed, 25 Feb 2015 20:32:40 -0500 From: Yijing Wang To: Bjorn Helgaas CC: Jiang Liu , , Yinghai Lu , , Marc Zyngier , , Russell King , , Thomas Gleixner , Benjamin Herrenschmidt , Rusty Russell , Tony Luck , , "David S. Miller" , "Guan Xuetao" , , , Liviu Dudau , "Arnd Bergmann" , Geert Uytterhoeven , "Yijing Wang" , Richard Henderson , "Ivan Kokshaysky" , Matt Turner , Subject: [PATCH v3 01/30] PCI: Rip out pci_bus_add_devices() from pci_scan_bus() Date: Thu, 26 Feb 2015 09:29:18 +0800 Message-ID: <1424914187-21027-2-git-send-email-wangyijing@huawei.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1424914187-21027-1-git-send-email-wangyijing@huawei.com> References: <1424914187-21027-1-git-send-email-wangyijing@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.100.166] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5437 Lines: 161 Pci_bus_add_devices() should not be placed in pci_scan_bus(). Now pci device will be added to driver core once its creation. All things left in pci_bus_add_devices() are driver attachment and other trivial sysfs things. Pci_scan_bus() should be the function responsible for scanning PCI devices, not including driver attachment. Other, some callers(m68k,unicore32,alpha) of pci_scan_bus() will call pci_bus_size_bridges() and pci_bus_assign_resources() after pci_scan_bus(). E.g. In m68k mcf_pci_init() pci_scan_bus() ... pci_bus_add_devices() --- try to attach driver pci_fixup_irqs() pci_bus_size_bridges() pci_bus_assign_resources() Above code flow make pci scan logic obscure, resources should be assigned correctly before attaching driver. Because pci_scan_bus() mostly be called in system boot path, when before drivers are loaded(in module_init), so no pci scan issues will occur. Most pci_scan_bus() callers additionally call pci_bus_size_bridges() and pci_bus_assign_resources() after pci_scan_bus(), we could rip out pci_bus_add_devices() for better code readability. After applied this patch, pci_scan_bus() should be used like: pci_scan_bus() (mandatory) pci_fixup_irqs() (optional) pci_bus_size_bridges() (optional) pci_pci_bus_assign_resources() (optional) pci_bus_add_devices() (mandatory) Signed-off-by: Yijing Wang CC: "David S. Miller" CC: Geert Uytterhoeven CC: Guan Xuetao CC: Richard Henderson CC: Ivan Kokshaysky CC: Matt Turner CC: linux-alpha@vger.kernel.org CC: linux-m68k@lists.linux-m68k.org CC: sparclinux@vger.kernel.org --- arch/alpha/kernel/sys_nautilus.c | 1 + arch/m68k/coldfire/pci.c | 1 + arch/sparc/kernel/pcic.c | 2 ++ arch/unicore32/kernel/pci.c | 11 +++-------- drivers/pci/hotplug/ibmphp_core.c | 6 ++++-- drivers/pci/probe.c | 1 - 6 files changed, 11 insertions(+), 11 deletions(-) diff --git a/arch/alpha/kernel/sys_nautilus.c b/arch/alpha/kernel/sys_nautilus.c index 837c0fa..4ae4a40 100644 --- a/arch/alpha/kernel/sys_nautilus.c +++ b/arch/alpha/kernel/sys_nautilus.c @@ -253,6 +253,7 @@ nautilus_init_pci(void) for the root bus, so just clear it. */ bus->self = NULL; pci_fixup_irqs(alpha_mv.pci_swizzle, alpha_mv.pci_map_irq); + pci_bus_add_devices(bus); } /* diff --git a/arch/m68k/coldfire/pci.c b/arch/m68k/coldfire/pci.c index df96792..d45f087 100644 --- a/arch/m68k/coldfire/pci.c +++ b/arch/m68k/coldfire/pci.c @@ -319,6 +319,7 @@ static int __init mcf_pci_init(void) pci_fixup_irqs(pci_common_swizzle, mcf_pci_map_irq); pci_bus_size_bridges(rootbus); pci_bus_assign_resources(rootbus); + pci_bus_add_devices(rootbus); return 0; } diff --git a/arch/sparc/kernel/pcic.c b/arch/sparc/kernel/pcic.c index 6cc78c2..7a82fe2 100644 --- a/arch/sparc/kernel/pcic.c +++ b/arch/sparc/kernel/pcic.c @@ -391,6 +391,8 @@ static void __init pcic_pbm_scan_bus(struct linux_pcic *pcic) struct linux_pbm_info *pbm = &pcic->pbm; pbm->pci_bus = pci_scan_bus(pbm->pci_first_busno, &pcic_ops, pbm); + if (pbm->pci_bus) + pci_bus_add_devices(pbm->pci_bus); #if 0 /* deadwood transplanted from sparc64 */ pci_fill_in_pbm_cookies(pbm->pci_bus, pbm, pbm->prom_node); pci_record_assignments(pbm, pbm->pci_bus); diff --git a/arch/unicore32/kernel/pci.c b/arch/unicore32/kernel/pci.c index 374a055..3d82024 100644 --- a/arch/unicore32/kernel/pci.c +++ b/arch/unicore32/kernel/pci.c @@ -266,17 +266,12 @@ static int __init pci_common_init(void) pci_fixup_irqs(pci_common_swizzle, pci_puv3_map_irq); if (!pci_has_flag(PCI_PROBE_ONLY)) { - /* - * Size the bridge windows. - */ + /* Size the bridge windows. */ pci_bus_size_bridges(puv3_bus); - - /* - * Assign resources. - */ + /* Assign resources. */ pci_bus_assign_resources(puv3_bus); } - + pci_bus_add_devices(puv3_bus); return 0; } subsys_initcall(pci_common_init); diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c index 96c5c72..86e3bfd 100644 --- a/drivers/pci/hotplug/ibmphp_core.c +++ b/drivers/pci/hotplug/ibmphp_core.c @@ -738,7 +738,7 @@ static void ibm_unconfigure_device(struct pci_func *func) */ static u8 bus_structure_fixup(u8 busno) { - struct pci_bus *bus; + struct pci_bus *bus, *b; struct pci_dev *dev; u16 l; @@ -765,7 +765,9 @@ static u8 bus_structure_fixup(u8 busno) (l != 0x0000) && (l != 0xffff)) { debug("%s - Inside bus_structure_fixup()\n", __func__); - pci_scan_bus(busno, ibmphp_pci_bus->ops, NULL); + b = pci_scan_bus(busno, ibmphp_pci_bus->ops, NULL); + if (b) + pci_bus_add_devices(b); break; } } diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 8d2f400..88604f2 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2123,7 +2123,6 @@ struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources); if (b) { pci_scan_child_bus(b); - pci_bus_add_devices(b); } else { pci_free_resource_list(&resources); } -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/