Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751940AbdGaHmI (ORCPT ); Mon, 31 Jul 2017 03:42:08 -0400 Received: from verein.lst.de ([213.95.11.211]:56322 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750847AbdGaHmH (ORCPT ); Mon, 31 Jul 2017 03:42:07 -0400 Date: Mon, 31 Jul 2017 09:42:06 +0200 From: Christoph Hellwig To: Minchan Kim Cc: Christoph Hellwig , Andrew Morton , Matthew Wilcox , Ross Zwisler , linux-kernel@vger.kernel.org, "karam . lee" , Jerome Marchand , Nitin Gupta , seungho1.park@lge.com, Dan Williams , Dave Chinner , Jan Kara , Jens Axboe , Vishal Verma , linux-nvdimm@lists.01.org Subject: Re: [PATCH 0/3] remove rw_page() from brd, pmem and btt Message-ID: <20170731074206.GA16706@lst.de> References: <20170728165604.10455-1-ross.zwisler@linux.intel.com> <20170728173143.GE15980@bombadil.infradead.org> <20170728142123.729b20e9fcf45c6a814f18e7@linux-foundation.org> <20170730221659.GA28031@bbox> <20170731071707.GA16299@lst.de> <20170731073647.GA26199@bbox> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170731073647.GA26199@bbox> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 500 Lines: 10 On Mon, Jul 31, 2017 at 04:36:47PM +0900, Minchan Kim wrote: > Do you suggest define something special flag(e.g., SWP_INMEMORY) > for in-memory swap to swap_info_struct when swapon time manually > or from bdi_queue_someting automatically? > And depending the flag of swap_info_struct, use the onstack bio > instead of dynamic allocation if the swap device is in-memory? Currently swap always just does I/O on a single page as far as I can tell, so it can always just use an on-stack bio and biovec.