From: "Rafael J. Wysocki" Subject: Re: [PATCH] DRM / radeon / PM: Do not evict VRAM during freeze phase of hibernation Date: Sat, 19 Jun 2010 01:23:00 +0200 Message-ID: <201006190123.00694.rjw@sisk.pl> References: <201006182221.57333.rjw@sisk.pl> <1276895296.6513.3.camel@t60prh> Mime-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1276895296.6513.3.camel@t60prh> Sender: linux-kernel-owner@vger.kernel.org To: Dave Airlie Cc: linux-kernel@vger.kernel.org, dri-devel , linux-pm@lists.linux-foundation.org, Alex Deucher , Andrew Morton , Ondrej Zary List-Id: dri-devel@lists.freedesktop.org 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. :-) If you don't like it, though, I guess it will be necessary to find the root cause of the delay. Rafael