On Thu, Apr 12, 2012 at 12:38:09AM +0100, Chris Wilson wrote: > On Thu, 12 Apr 2012 01:27:57 +0200, Daniel Vetter <daniel.vetter at ffwll.ch> wrote: > > This fixes a regression introduce in > s/introduce/introduced/ > > > commit 7dd4906586274f3945f2aeaaa5a33b451c3b4bba > > Author: Chris Wilson <chris at chris-wilson.co.uk> > > Date: Wed Mar 21 10:48:18 2012 +0000 > > > > drm/i915: Mark untiled BLT commands as fenced on gen2/3 > > > > which fixed fencing tracking for untiled blt commands. > > > > A side effect of that patch was that now also untiled objects have a > > non-zero obj->last_fenced_seqno to track when a fence can be set up > > after a pipelined tiling change. Unfortunately this was only cleared > > by the fence setup and teardown code, resulting in tons of untiled but > > inactive objects with non-zero last_fenced_seqno. > > > > Now after resume we completely reset the seqno tracking, both on the > > driver side (by setting dev_priv->next_seqno = 1) and on the hw side > > (by allocating a new hws page, which contains the seqnos). Hilarity > > and indefinite waits ensued from the stale seqnos in > > obj->last_fenced_seqno from before the suspend. > > > > The fix is to properly clear the fencing tracking state like we > > already do for the normal gpu rendering while moving objects off the > > active list. > > > > Reported-and-tested-by: "Rafael J. Wysocki" <rjw at sisk.pl> > > Cc: Jiri Slaby <jslaby at suse.cz> > > Signed-Off-by: Daniel Vetter <daniel.vetter at ffwll.ch> > > I spent sometime discussing whether or not we could hit a similar bug > with a well placed change of tiling after resume, and the outcome is > that as the fences are reset during freeze then all tiled objects that > had been used for rendering would have been flushed (and their > last_fenced_seqno set to 0). > > So this is a new regression caused by the aforementioned patch and this > is the cleanest fix, > Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk> Picked up for -fixes, thanks for the review. -Daniel -- Daniel Vetter Mail: daniel at ffwll.ch Mobile: +41 (0)79 365 57 48
