Re: [PATCH] drm/ttm: Don't evict BOs outside of the requested placement range

[Greg KH <gregkh@linuxfoundation.org>]

On Sat, Oct 11, 2014 at 08:31:49PM +0200, Daniel Vetter wrote:
> On Fri, Oct 10, 2014 at 05:59:19PM +0900, Michel Dänzer wrote:
> > On 10.10.2014 17:51, Alan Swanson wrote:
> > >On Fri, 2014-10-10 at 12:20 +0900, Michel Dänzer wrote:
> > >>On 09.10.2014 19:22, Alan Swanson wrote:
> > >>>On 2014-10-09 07:02, Michel Dänzer wrote:
> > >>>>From: Michel Dänzer <michel.daenzer@amd.com>
> > >>>>
> > >>>>The radeon driver uses placement range restrictions for several reasons,
> > >>>>in particular to make sure BOs in VRAM can be accessed by the CPU, e.g.
> > >>>>during a page fault.
> > >>>>
> > >>>>Without this change, TTM could evict other BOs while trying to satisfy
> > >>>>the requested placement, even if the evicted BOs were outside of the
> > >>>>requested placement range. Doing so didn't free up any space in the
> > >>>>requested placement range, so the (potentially high) eviction cost was
> > >>>>incurred for no benefit.
> > >>>>
> > >>>>Nominating for stable because radeon driver changes in 3.17 made this
> > >>>>much more noticeable than before.
> > >>>>
> > >>>>Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=84662
> > >>>>Cc: stable@vger.kernel.org
> > >>>>Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
> > >>>>---
> > >>>>  drivers/gpu/drm/ttm/ttm_bo.c | 20 +++++++++++++++++---
> > >>>>  1 file changed, 17 insertions(+), 3 deletions(-)
> > >>>>
> > >>[...]
> > >>
> > >>>I believe you need to "s/place/placement/" over this patch.
> > >>
> > >>The fpfn and lpfn members were moved from struct ttm_placement to a new
> > >>struct ttm_place in f1217ed09f827e42a49ffa6a5aab672aa6f57a65.
> > >>
> > >>If you mean something else, please elaborate.
> > >
> > >This patch failed to build on 3.17.0 so wouldn't be a candidate for
> > >stable unless the currently drm-next only ttm_place patch also goes to
> > >stable (else replace ttm_place with ttm_placements in the patch for
> > >stable)?
> > 
> > Right, I guess I should drop the Cc: stable then and submit a manual
> > backport of it to the stable list once it has landed in Linus' tree.
> 
> I've thought it's ok to cc: stable a patch - Greg's scripts will send you
> a mail as a nice reminder if the patch fails to apply. At least we
> regularly pull this stunt with i915 patches. Cc'ing Greg for
> clarification.

Yup, that's fine to do, it's what the scripts are for :)