From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vk0-f71.google.com (mail-vk0-f71.google.com [209.85.213.71]) by kanga.kvack.org (Postfix) with ESMTP id AA60D6B0387 for ; Mon, 13 Feb 2017 11:01:28 -0500 (EST) Received: by mail-vk0-f71.google.com with SMTP id x75so68215261vke.5 for ; Mon, 13 Feb 2017 08:01:28 -0800 (PST) Received: from bombadil.infradead.org (bombadil.infradead.org. [65.50.211.133]) by mx.google.com with ESMTPS id n83si10442201pfj.15.2017.02.13.08.01.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 13 Feb 2017 08:01:27 -0800 (PST) Date: Mon, 13 Feb 2017 08:01:17 -0800 From: Matthew Wilcox Subject: Re: [PATCHv6 08/37] filemap: handle huge pages in do_generic_file_read() Message-ID: <20170213160117.GA6416@bombadil.infradead.org> References: <20170126115819.58875-1-kirill.shutemov@linux.intel.com> <20170126115819.58875-9-kirill.shutemov@linux.intel.com> <20170209215505.GW2267@bombadil.infradead.org> <20170213153342.GE20394@node.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170213153342.GE20394@node.shutemov.name> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: "Kirill A. Shutemov" , 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 Mon, Feb 13, 2017 at 06:33:42PM +0300, Kirill A. Shutemov wrote: > No. pagecache_get_page() returns subpage. See description of the first > patch. Your description says: > We also change interface for page-cache lookup function: > > - functions that lookup for pages[1] would return subpages of THP > relevant for requested indexes; > > - functions that lookup for entries[2] would return one entry per-THP > and index will point to index of head page (basically, round down to > HPAGE_PMD_NR); > > This would provide balanced exposure of multi-order entires to the rest > of the kernel. > > [1] find_get_pages(), pagecache_get_page(), pagevec_lookup(), etc. > [2] find_get_entry(), find_get_entries(), pagevec_lookup_entries(), etc. I'm saying: > > We got this page from find_get_page(), which gets it from > > pagecache_get_page(), which gets it from find_get_entry() ... which > > (unless I'm lost in your patch series) returns the head page. Am I guilty of debugging documentation rather than code? -- 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