Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758470Ab1EZUzd (ORCPT ); Thu, 26 May 2011 16:55:33 -0400 Received: from mail-ww0-f44.google.com ([74.125.82.44]:45223 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753693Ab1EZUzb (ORCPT ); Thu, 26 May 2011 16:55:31 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=iuQiDsEkGm/95b0j/osFLa8Gkp+TxB+1EhNQ+RlUAV9Q+WCZvZgnP1HlbekzS64rZH jDC+O3k4txmp8wUNA0pnvLXFr8EDaYtiA+XA+n5stpF2Gr0BL4m/uMcahjoARNiTGLwJ 1MIqAsAg8gh/9Cku/Erl9LHfVGHxCYvw7MaqQ= Subject: Re: [PATCH V6 2/4 net-next] skbuff: Add userspace zero-copy buffers in skb From: Eric Dumazet To: Shirley Ma Cc: David Miller , mst@redhat.com, Avi Kivity , Arnd Bergmann , netdev@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <1306441442.5180.51.camel@localhost.localdomain> References: <1306438593.5180.33.camel@localhost.localdomain> <1306440247.2543.14.camel@edumazet-laptop> <1306441442.5180.51.camel@localhost.localdomain> Content-Type: text/plain; charset="UTF-8" Date: Thu, 26 May 2011 22:55:25 +0200 Message-ID: <1306443325.2543.22.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 818 Lines: 22 Le jeudi 26 mai 2011 à 13:24 -0700, Shirley Ma a écrit : > I could reduce callback pointer by moving it to *arg, but not desc, this > indicates that which buffer DMA hasn't done yet in *arg. I guess you dont need to use skb itself to hold all your states ? I understand its convenient for you, but I believe its worth the pain to use only one pointer to a (small) object where you put all your stuff. Some machines alloc/free millions of skbs per second. If/when most skb uses are for userspace zero-copy buffers we can embbed your small object in skb itself ;) -- 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/