From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx129.postini.com [74.125.245.129]) by kanga.kvack.org (Postfix) with SMTP id 4C5816B0031 for ; Thu, 12 Sep 2013 11:12:02 -0400 (EDT) Date: Thu, 12 Sep 2013 11:11:44 -0400 From: Naoya Horiguchi Message-ID: <1378998704-d94o0a30-mutt-n-horiguchi@ah.jp.nec.com> Subject: [PATCH] mm/hwpoison: move set_migratetype_isolate() outside get_any_page() Mime-Version: 1.0 Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Andi Kleen , Fengguang Wu , Wanpeng Li , Tony Luck , gong.chen@linux.intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Chen Gong pointed out that set/unset_migratetype_isolate() was done in different functions in mm/memory-failure.c, which makes the code less readable/maintenable. So this patch makes it done in soft_offline_page(). With this patch, we get to hold lock_memory_hotplug() longer but it's not a problem because races between memory hotplug and soft offline are very rare. This patch is against next-20130910. Signed-off-by: Naoya Horiguchi Reviewed-by: Chen, Gong --- mm/memory-failure.c | 36 +++++++++++++++++------------------- 1 file changed, 17 insertions(+), 19 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 947ed54..702e1e1 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1421,19 +1421,6 @@ static int __get_any_page(struct page *p, unsigned long pfn, int flags) return 1; /* - * The lock_memory_hotplug prevents a race with memory hotplug. - * This is a big hammer, a better would be nicer. - */ - lock_memory_hotplug(); - - /* - * Isolate the page, so that it doesn't get reallocated if it - * was free. This flag should be kept set until the source page - * is freed and PG_hwpoison on it is set. - */ - if (get_pageblock_migratetype(p) != MIGRATE_ISOLATE) - set_migratetype_isolate(p, true); - /* * When the target page is a free hugepage, just remove it * from free hugepage list. */ @@ -1453,7 +1440,6 @@ static int __get_any_page(struct page *p, unsigned long pfn, int flags) /* Not a free page */ ret = 1; } - unlock_memory_hotplug(); return ret; } @@ -1652,15 +1638,28 @@ int soft_offline_page(struct page *page, int flags) } } + /* + * The lock_memory_hotplug prevents a race with memory hotplug. + * This is a big hammer, a better would be nicer. + */ + lock_memory_hotplug(); + + /* + * Isolate the page, so that it doesn't get reallocated if it + * was free. This flag should be kept set until the source page + * is freed and PG_hwpoison on it is set. + */ + if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE) + set_migratetype_isolate(page, true); + ret = get_any_page(page, pfn, flags); - if (ret < 0) - goto unset; - if (ret) { /* for in-use pages */ + unlock_memory_hotplug(); + if (ret > 0) { /* for in-use pages */ if (PageHuge(page)) ret = soft_offline_huge_page(page, flags); else ret = __soft_offline_page(page, flags); - } else { /* for free pages */ + } else if (ret == 0) { /* for free pages */ if (PageHuge(page)) { set_page_hwpoison_huge_page(hpage); dequeue_hwpoisoned_huge_page(hpage); @@ -1671,7 +1670,6 @@ int soft_offline_page(struct page *page, int flags) atomic_long_inc(&num_poisoned_pages); } } -unset: unset_migratetype_isolate(page, MIGRATE_MOVABLE); return ret; } -- 1.8.3.1 -- 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