From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f46.google.com (mail-oi0-f46.google.com [209.85.218.46]) by kanga.kvack.org (Postfix) with ESMTP id 917276B0036 for ; Tue, 29 Jul 2014 03:37:47 -0400 (EDT) Received: by mail-oi0-f46.google.com with SMTP id i138so7082230oig.33 for ; Tue, 29 Jul 2014 00:37:47 -0700 (PDT) Received: from szxga03-in.huawei.com (szxga03-in.huawei.com. [119.145.14.66]) by mx.google.com with ESMTPS id x1si48763452obg.89.2014.07.29.00.37.43 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 29 Jul 2014 00:37:46 -0700 (PDT) Message-ID: <53D74EE5.1070308@huawei.com> Date: Tue, 29 Jul 2014 15:36:05 +0800 From: Zhang Zhen MIME-Version: 1.0 Subject: [PATCH v2] memory hotplug: update the variables after memory removed References: <1406619310-20555-1-git-send-email-zhenzhang.zhang@huawei.com> In-Reply-To: <1406619310-20555-1-git-send-email-zhenzhang.zhang@huawei.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes , Dave Hansen , mgorman@suse.de, mingo@redhat.com, akpm@linux-foundation.org Cc: wangnan0@huawei.com, Linux MM , linux-kernel@vger.kernel.org Commit ea0854170c95245a258b386c7a9314399c949fe0 added a fuction update_end_of_memory_vars() to update high_memory, max_pfn and max_low_pfn. I modified the function according to Dave Hansen and David Rientjes's suggestions. And call it in arch_remove_memory() to update these variables too. Change v1->v2: - according to Dave Hansen and David Rientjes's suggestions modified update_end_of_memory_vars(). Signed-off-by: Zhang Zhen --- arch/x86/mm/init_64.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index df1a992..fd7bd6b 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -673,15 +673,11 @@ void __init paging_init(void) * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need * updating. */ -static void update_end_of_memory_vars(u64 start, u64 size) +static void update_end_of_memory_vars(u64 end_pfn) { - unsigned long end_pfn = PFN_UP(start + size); - - if (end_pfn > max_pfn) { - max_pfn = end_pfn; - max_low_pfn = end_pfn; - high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; - } + max_pfn = end_pfn; + max_low_pfn = end_pfn; + high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; } /* @@ -694,6 +690,7 @@ int arch_add_memory(int nid, u64 start, u64 size) struct zone *zone = pgdat->node_zones + ZONE_NORMAL; unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; + unsigned long end_pfn; int ret; init_memory_mapping(start, start + size); @@ -702,7 +699,9 @@ int arch_add_memory(int nid, u64 start, u64 size) WARN_ON_ONCE(ret); /* update max_pfn, max_low_pfn and high_memory */ - update_end_of_memory_vars(start, size); + end_pfn = start_pfn + nr_pages; + if (end_pfn > max_pfn) + update_end_of_memory_vars(end_pfn); return ret; } @@ -1018,6 +1017,7 @@ int __ref arch_remove_memory(u64 start, u64 size) unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; struct zone *zone; + unsigned long end_pfn; int ret; zone = page_zone(pfn_to_page(start_pfn)); @@ -1025,6 +1025,11 @@ int __ref arch_remove_memory(u64 start, u64 size) ret = __remove_pages(zone, start_pfn, nr_pages); WARN_ON_ONCE(ret); + /* update max_pfn, max_low_pfn and high_memory */ + end_pfn = start_pfn + nr_pages; + if ((max_pfn >= start_pfn) && (max_pfn < end_pfn)) + update_end_of_memory_vars(start_pfn); + return ret; } #endif -- 1.8.1.2 . -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org