From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f72.google.com (mail-pg0-f72.google.com [74.125.83.72]) by kanga.kvack.org (Postfix) with ESMTP id C8B036B0038 for ; Fri, 10 Feb 2017 12:46:36 -0500 (EST) Received: by mail-pg0-f72.google.com with SMTP id 194so58359857pgd.7 for ; Fri, 10 Feb 2017 09:46:36 -0800 (PST) Received: from bombadil.infradead.org (bombadil.infradead.org. [65.50.211.133]) by mx.google.com with ESMTPS id 34si2279819plz.118.2017.02.10.09.46.35 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 10 Feb 2017 09:46:36 -0800 (PST) Date: Fri, 10 Feb 2017 09:46:10 -0800 From: Matthew Wilcox Subject: Re: [PATCHv6 13/37] mm: make write_cache_pages() work on huge pages Message-ID: <20170210174610.GC2267@bombadil.infradead.org> References: <20170126115819.58875-1-kirill.shutemov@linux.intel.com> <20170126115819.58875-14-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170126115819.58875-14-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: Theodore Ts'o , Andreas Dilger , Jan Kara , Andrew Morton , Alexander Viro , Hugh Dickins , Andrea Arcangeli , Dave Hansen , Vlastimil Babka , Ross Zwisler , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org On Thu, Jan 26, 2017 at 02:57:55PM +0300, Kirill A. Shutemov wrote: > We writeback whole huge page a time. Let's adjust iteration this way. > > Signed-off-by: Kirill A. Shutemov I think a lot of the complexity in this patch is from pagevec_lookup_tag giving you subpages rather than head pages... > @@ -2268,7 +2273,8 @@ int write_cache_pages(struct address_space *mapping, > * not be suitable for data integrity > * writeout). > */ > - done_index = page->index + 1; > + done_index = compound_head(page)->index > + + hpage_nr_pages(page); > done = 1; > break; > } you'd still need this line, but it'd only be: done_index = page->index + (1 << compound_order(page)); I think we want: #define nr_pages(page) (1 << compound_order(page)) because we seem to be repeating that idiom quite a lot in these patches. done_index = page->index + nr_pages(page); Still doesn't quite fit on one line, but it's closer, and it's the ridiculous indentation in that function that's the real problem. -- 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