Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932312AbcDHARP (ORCPT ); Thu, 7 Apr 2016 20:17:15 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:42359 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932215AbcDHARL (ORCPT ); Thu, 7 Apr 2016 20:17:11 -0400 From: Yinghai Lu To: Bjorn Helgaas , David Miller , Benjamin Herrenschmidt , Linus Torvalds Cc: Wei Yang , TJ , Yijing Wang , Khalid Aziz , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Yinghai Lu Subject: [PATCH v11 21/60] PCI: Treat optional as required in first try for bridge rescan Date: Thu, 7 Apr 2016 17:15:34 -0700 Message-Id: <1460074573-7481-22-git-send-email-yinghai@kernel.org> X-Mailer: git-send-email 1.8.4.5 In-Reply-To: <1460074573-7481-1-git-send-email-yinghai@kernel.org> References: <1460074573-7481-1-git-send-email-yinghai@kernel.org> X-Source-IP: userv0021.oracle.com [156.151.31.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2458 Lines: 70 For rescan bridge/bus that children are removed before, we should treat optional as required just like root bus the boot time in 19aa7ee432ce (PCI: make re-allocation try harder by reassigning ranges higher in the heirarchy). The reason: allocate required and expand to optional path do not put failed resource to fail list, so will lose required info before next try. So we are using following way: 1. First and following try before last try: We don't keep realloc list so treat every optional as required. allocate for required+optional and put failed in the fail list. then size info (include must and optonal separatedly) will be kept for next try. 2. last try: a: try to allocate required+optional to see if all get allocated. b: try to allocate required then expand to optional. Signed-off-by: Yinghai Lu --- drivers/pci/setup-bus.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 7d58f3f..3dc4ac9 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1845,25 +1845,34 @@ void __init pci_assign_unassigned_resources(void) void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge) { struct pci_bus *parent = bridge->subordinate; - LIST_HEAD(add_list); /* list of resources that + LIST_HEAD(realloc_head); /* list of resources that want additional resources */ + struct list_head *add_list = NULL; int tried_times = 0; LIST_HEAD(fail_head); struct pci_dev_resource *fail_res; int retval; unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_MEM_64; + int pci_try_num = 2; again: - __pci_bus_size_bridges(parent, &add_list); - __pci_bridge_assign_resources(bridge, &add_list, &fail_head); - pci_bus_check_realloc(&add_list); + /* + * last try will use add_list, otherwise will try good to have as + * must have, so can realloc parent bridge resource + */ + if (tried_times + 1 == pci_try_num) + add_list = &realloc_head; + __pci_bus_size_bridges(parent, add_list); + __pci_bridge_assign_resources(bridge, add_list, &fail_head); + if (add_list) + pci_bus_check_realloc(add_list); tried_times++; if (list_empty(&fail_head)) goto enable_all; - if (tried_times >= 2) { + if (tried_times >= pci_try_num) { /* still fail, don't need to try more */ free_list(&fail_head); goto enable_all; -- 1.8.4.5