From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [PATCH] x86: Enable fast 32-bit put_user_64 for copy_to_user Date: Thu, 16 Apr 2015 09:28:02 +0200 Message-ID: <20150416072802.GA4998@gmail.com> References: <1429091486-11443-1-git-send-email-chris@chris-wilson.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail-wi0-f181.google.com (mail-wi0-f181.google.com [209.85.212.181]) by gabe.freedesktop.org (Postfix) with ESMTP id 2BE276E974 for ; Thu, 16 Apr 2015 00:28:06 -0700 (PDT) Received: by wiun10 with SMTP id n10so86349913wiu.1 for ; Thu, 16 Apr 2015 00:28:05 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1429091486-11443-1-git-send-email-chris@chris-wilson.co.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Chris Wilson Cc: intel-gfx@lists.freedesktop.org, x86@kernel.org, linux-kernel@vger.kernel.org, Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner List-Id: intel-gfx@lists.freedesktop.org CiogQ2hyaXMgV2lsc29uIDxjaHJpc0BjaHJpcy13aWxzb24uY28udWs+IHdyb3RlOgoKPiBGb3Ig Zml4ZWQgc2l6ZWQgY29waWVzLCBjb3B5X3RvX3VzZXIoKSB3aWxsIHV0aWxpemUgX19wdXRfdXNl cl9zaXplCj4gZmFzdHBhdGhzLiBIb3dldmVyLCBpdCBpcyBtaXNzaW5nIHRoZSB0cmFuc2xhdGlv biBmb3IgNjRiaXQgY29waWVzIG9uCj4geDg2LzMyLiBUZXN0aW5nIG9uIGEgUGluZXRyYWlsIEF0 b20sIHRoZSA2NCBiaXQgcHV0X3VzZXIgZmFzdHBhdGggaXMKPiBzdWJzdGFudGlhbGx5IGZhc3Rl ciB0aGFuIHRoZSBnZW5lcmljIGNvcHlfdG9fdXNlcigpIGZhbGxiYWNrLgo+IAo+IENjOiBUaG9t YXMgR2xlaXhuZXIgPHRnbHhAbGludXRyb25peC5kZT4KPiBDYzogSW5nbyBNb2xuYXIgPG1pbmdv QHJlZGhhdC5jb20+Cj4gQ2M6ICJILiBQZXRlciBBbnZpbiIgPGhwYUB6eXRvci5jb20+Cj4gQ2M6 IHg4NkBrZXJuZWwub3JnCj4gQ0M6IGxpbnV4LWtlcm5lbEB2Z2VyLmtlcm5lbC5vcmcKClRoZSBw YXRjaCBtYWtlcyBzZW5zZSwgYnV0IHlvdXIgU2lnbmVkLW9mZi1ieSBsaW5lIGlzIG1pc3Npbmcu CgpUaGFua3MsCgoJSW5nbwpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fXwpJbnRlbC1nZnggbWFpbGluZyBsaXN0CkludGVsLWdmeEBsaXN0cy5mcmVlZGVza3Rv cC5vcmcKaHR0cDovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2ludGVs LWdmeAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756930AbbDPH2N (ORCPT ); Thu, 16 Apr 2015 03:28:13 -0400 Received: from mail-wi0-f169.google.com ([209.85.212.169]:34031 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753998AbbDPH2G (ORCPT ); Thu, 16 Apr 2015 03:28:06 -0400 Date: Thu, 16 Apr 2015 09:28:02 +0200 From: Ingo Molnar To: Chris Wilson Cc: intel-gfx@lists.freedesktop.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86: Enable fast 32-bit put_user_64 for copy_to_user Message-ID: <20150416072802.GA4998@gmail.com> References: <1429091486-11443-1-git-send-email-chris@chris-wilson.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1429091486-11443-1-git-send-email-chris@chris-wilson.co.uk> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Chris Wilson wrote: > For fixed sized copies, copy_to_user() will utilize __put_user_size > fastpaths. However, it is missing the translation for 64bit copies on > x86/32. Testing on a Pinetrail Atom, the 64 bit put_user fastpath is > substantially faster than the generic copy_to_user() fallback. > > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: "H. Peter Anvin" > Cc: x86@kernel.org > CC: linux-kernel@vger.kernel.org The patch makes sense, but your Signed-off-by line is missing. Thanks, Ingo