Re: [PATCH] [v3] drm: pre allocate node for create_block

[Daniel Vetter <daniel@ffwll.ch>]

On Thu, Jul 04, 2013 at 10:32:27PM +0200, David Herrmann wrote:
> Hi
> 
> On Thu, Jul 4, 2013 at 10:14 PM, Ben Widawsky <ben@bwidawsk.net> wrote:
> > For an upcoming patch where we introduce the i915 VMA, it's ideal to
> > have the drm_mm_node as part of the VMA struct (ie. it's pre-allocated).
> > Part of the conversion to VMAs is to kill off obj->gtt_space. Doing this
> > will break a bunch of code, but amongst them are 2 callers of
> > drm_mm_create_block(), both related to stolen memory.
> >
> > It also allows us to embed the drm_mm_node into the object currently
> > which provides a nice transition over to the new code.
> >
> > v2: Reordered to do before ripping out obj->gtt_offset.
> > Some minor cleanups made available because of reordering.
> >
> > v3: s/continue/break on failed stolen node allocation (David)
> > Set obj->gtt_space on failed node allocation (David)
> > Only unref stolen (fix double free) on failed create_stolen (David)
> > Free node, and NULL it in failed create_stolen (David)
> > Add back accidentally removed newline (David)
> >
> > CC: <dri-devel@lists.freedesktop.org>
> > CC: David Herrmann <dh.herrmann@gmail.com>
> > Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> 
> I already suspected that you'd embed drm_mm_node in a follow-up patch
> but I am not subscribed to intel-gfx so I didn't get the other
> patches. Looks good now.
> 
> Reviewed-by: David Herrmann <dh.herrmann@gmail.com>

Ok, I've discussed this a bit with Dave on irc and he's a bit unhappy with
the creat_block name. After a bit of chatting with Ben I think we should
go with

int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);

The start/size/color arguments would then be passed in through the
drm_mm_node argument. Ben asked whether that's not too much poking around
in drm_mm_node internals, but imo those three pieces of it are part of the
public interface to drm_mm users.

Also, the patch as-is conflicts a bit too badly with my current tree. So
can you please apply the little bikeshed, rebase, and then rebase the
other patches in this series that I haven't merged on top of this?

Thanks, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch