From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx168.postini.com [74.125.245.168]) by kanga.kvack.org (Postfix) with SMTP id B60BF6B0027 for ; Thu, 21 Mar 2013 12:13:56 -0400 (EDT) Message-ID: <514B320C.4030507@sr71.net> Date: Thu, 21 Mar 2013 09:15:08 -0700 From: Dave Hansen MIME-Version: 1.0 Subject: Re: [PATCHv2, RFC 05/30] thp, mm: avoid PageUnevictable on active/inactive lru lists References: <1363283435-7666-1-git-send-email-kirill.shutemov@linux.intel.com> <1363283435-7666-6-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1363283435-7666-6-git-send-email-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: Andrea Arcangeli , Andrew Morton , Al Viro , Hugh Dickins , Wu Fengguang , Jan Kara , Mel Gorman , linux-mm@kvack.org, Andi Kleen , Matthew Wilcox , "Kirill A. Shutemov" , Hillf Danton , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org On 03/14/2013 10:50 AM, Kirill A. Shutemov wrote: > active/inactive lru lists can contain unevicable pages (i.e. ramfs pages > that have been placed on the LRU lists when first allocated), but these > pages must not have PageUnevictable set - otherwise shrink_active_list > goes crazy: ... > For lru_add_page_tail(), it means we should not set PageUnevictable() > for tail pages unless we're sure that it will go to LRU_UNEVICTABLE. > The tail page will go LRU_UNEVICTABLE if head page is not on LRU or if > it's marked PageUnevictable() too. This is only an issue once you're using lru_add_page_tail() for non-anonymous pages, right? > diff --git a/mm/swap.c b/mm/swap.c > index 92a9be5..31584d0 100644 > --- a/mm/swap.c > +++ b/mm/swap.c > @@ -762,7 +762,8 @@ void lru_add_page_tail(struct page *page, struct page *page_tail, > lru = LRU_INACTIVE_ANON; > } > } else { > - SetPageUnevictable(page_tail); > + if (!PageLRU(page) || PageUnevictable(page)) > + SetPageUnevictable(page_tail); > lru = LRU_UNEVICTABLE; > } You were saying above that ramfs pages can get on the normal active/inactive lists. But, this will end up getting them on the unevictable list, right? So, we have normal ramfs pages on the active/inactive lists, but ramfs pages after a huge-page-split on the unevictable list. That seems a bit inconsistent. -- 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