Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754613Ab3HAKKv (ORCPT ); Thu, 1 Aug 2013 06:10:51 -0400 Received: from smtp.citrix.com ([66.165.176.89]:51164 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753371Ab3HAKKu (ORCPT ); Thu, 1 Aug 2013 06:10:50 -0400 X-IronPort-AV: E=Sophos;i="4.89,793,1367971200"; d="scan'208";a="40707583" Message-ID: <51FA3428.9020403@citrix.com> Date: Thu, 1 Aug 2013 11:10:48 +0100 From: David Vrabel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.16) Gecko/20121215 Iceowl/1.0b1 Icedove/3.0.11 MIME-Version: 1.0 To: Roger Pau Monne CC: , , David Vrabel Subject: Re: [Xen-devel] [PATCH 2/3] xen-blkfront: improve aproximation of required grants per request References: <1375282844-4314-1-git-send-email-roger.pau@citrix.com> <1375282844-4314-3-git-send-email-roger.pau@citrix.com> In-Reply-To: <1375282844-4314-3-git-send-email-roger.pau@citrix.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.2.76] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 747 Lines: 18 On 31/07/13 16:00, Roger Pau Monne wrote: > Improve the calculation of required grants to process a request by > using nr_phys_segments instead of always assuming a request is going > to use all posible segments. > > nr_phys_segments contains the number of scatter-gather DMA addr+len > pairs, which is basically what we put at every granted page. > for_each_sg iterates over the DMA addr+len pairs and uses a grant > page for each of them. Reviewed-by: David Vrabel David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/