From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH 1/2] drm/i915: time out of load detect busy-waits Date: Fri, 20 Apr 2012 20:42:10 +0100 Message-ID: <1334950954_7743@CP5-2952> References: <1334948616-16073-1-git-send-email-daniel.vetter@ffwll.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from fireflyinternet.com (smtp.fireflyinternet.com [109.228.6.236]) by gabe.freedesktop.org (Postfix) with ESMTP id 9AC0A9E73D for ; Fri, 20 Apr 2012 12:42:41 -0700 (PDT) In-Reply-To: <1334948616-16073-1-git-send-email-daniel.vetter@ffwll.ch> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Intel Graphics Development Cc: Daniel Vetter List-Id: intel-gfx@lists.freedesktop.org On Fri, 20 Apr 2012 21:03:35 +0200, Daniel Vetter wrote: > If we try to do that and the scanlines just wouldn't advance, we > busy-hang the machine holding the modeset mutex. Not great for > debugging. > > References: https://bugzilla.kernel.org/show_bug.cgi?id=43020 > Signed-off-by: Daniel Vetter A second is a bit much, 5 vblanks should do, say 100ms, but this is just paranoid code. Unfortunately if it hits it means the machine is likely to keep hitting it. Are little, but noticeable periodic stutters actually better than a freeze? Otherwise, Reviewed-by: Chris Wilson -Chris -- Chris Wilson, Intel Open Source Technology Centre