Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754084AbbDJGXo (ORCPT ); Fri, 10 Apr 2015 02:23:44 -0400 Received: from mail.fireflyinternet.com ([87.106.93.118]:65085 "EHLO fireflyinternet.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751536AbbDJGXl (ORCPT ); Fri, 10 Apr 2015 02:23:41 -0400 X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Date: Fri, 10 Apr 2015 07:23:31 +0100 From: Chris Wilson To: Olivier =?iso-8859-1?Q?Cr=EAte?= Cc: Brad Volkin , Daniel Vetter , Jani Nikula , David Airlie , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: libva decoding performance regression with kernel 4.0-rc Message-ID: <20150410062331.GE20904@nuc-i3427.alporthouse.com> Mail-Followup-To: Chris Wilson , Olivier =?iso-8859-1?Q?Cr=EAte?= , Brad Volkin , Daniel Vetter , Jani Nikula , David Airlie , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <1428627643.3417.22.camel@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1428627643.3417.22.camel@collabora.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1310 Lines: 33 On Thu, Apr 09, 2015 at 09:00:43PM -0400, Olivier Cr?te wrote: > Hello, > > Using an Atom E3845 board, we had a pretty bad performance regression > when upgrading to 4.0-rc6 from 3.19. With the help of git bisect, I > traced it back to commit 78a42377. Reverting this commit and subsequent > related commits (b9ffd80, 71745376, etc) fixes the performance > regression for me. Can you please test http://cgit.freedesktop.org/~ickle/linux-2.6/log/?h=for-olivier-crete on your setup. First http://cgit.freedesktop.org/~ickle/linux-2.6/commit/?h=for-olivier-crete&id=044307a99b418258ac0d775460d73b20b80277c1 to get a baseline with nightly as that contains some fine tuning to the batch allocations, which is pretty significant for libva on Atom (only double clflushing one or two pages every batch rather than 128) and then http://cgit.freedesktop.org/~ickle/linux-2.6/commit/?h=for-olivier-crete&id=0a24802a5b61403b887ce401ce3efd52f5fd1eac to see if the command parser tuning helps. Hope this helps, -Chris -- Chris Wilson, Intel Open Source Technology Centre -- 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/