Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755766Ab0FSMzp (ORCPT ); Sat, 19 Jun 2010 08:55:45 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:55669 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755667Ab0FSMzn (ORCPT ); Sat, 19 Jun 2010 08:55:43 -0400 From: "Rafael J. Wysocki" To: Dave Airlie Subject: Re: [PATCH] DRM / radeon / PM: Do not evict VRAM during freeze phase of hibernation Date: Sat, 19 Jun 2010 14:53:58 +0200 User-Agent: KMail/1.13.3 (Linux/2.6.35-rc3-rjw+; KDE/4.4.3; x86_64; ; ) Cc: linux-kernel@vger.kernel.org, "dri-devel" , linux-pm@lists.linux-foundation.org, Alex Deucher , Andrew Morton , Ondrej Zary References: <201006182221.57333.rjw@sisk.pl> <201006190123.00694.rjw@sisk.pl> <1276904995.6513.7.camel@t60prh> In-Reply-To: <1276904995.6513.7.camel@t60prh> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201006191453.58379.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2727 Lines: 59 On Saturday, June 19, 2010, Dave Airlie wrote: > On Sat, 2010-06-19 at 01:23 +0200, Rafael J. Wysocki wrote: > > On Friday, June 18, 2010, Dave Airlie wrote: > > > On Fri, 2010-06-18 at 22:21 +0200, Rafael J. Wysocki wrote: > > > > From: Rafael J. Wysocki > > > > > > > > I have recently noticed a 55 sec. delay during the "device freeze" > > > > phase of hibernation on my test-bed HP nx6325. Due to the 100% > > > > reproducibility of it I was able to narrow it down to > > > > radeon_suspend_kms() and then it turned out that the delay occured > > > > somewhere in radeon_bo_evict_vram(). However, it doesn't seem really > > > > necessary or even very useful to me to evict VRAM at this particular > > > > point, because we're going to create an image and bring the device > > > > back to the fully functional state in a little while. Thus, I think > > > > the VRAM evicition can be skipped for state.event == PM_EVENT_FREEZE, > > > > which makes the delay go away. > > > > > > I'm not 100% sure of the hibernate sequencing and its early in the > > > morning, but we want to evict VRAM before image building so we can have > > > the contents of VRAM in the image so we can restore them on resume. Does > > > this just avoid evicting them a second time after we created the image? > > > > No, it's the first time, before creating the image, but I didn't seen any > > difference on resume with and without the patch, so I thought it was a good > > idea. :-) > > On the machine you have its most likely not going to show up unless you > are running a 3D app or something across suspend, since currently X > re-exposes most apps on VT switch, so they just redraw. Yes. Moreover, hibernation is always done after a VT switch. That's why I said I thought the eviction wasn't necessary in the changelog. BTW, I have three different test boxes with radeon hardware and the $subject patch is not a problem on any of them. > Was it always this slow? Nope. It definitely is a regression, although I'm not sure what's the last good kernel. > you can see how many objects are in vram using > debugfs (/sys/kernel/debug/dri/0/radeon_vram_mm), it sounds like the TTM > eviction process is blocking on something, Yup. > we shouldn't be using any UC/WC memory on that machine so I can't imagine > the new pool allocator stuff would get in the way. Maybe its the lack of > GFP_USER, (Jerome posted a patch). Can you give me a pointer to that patch, please? Rafael -- 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/