[PATCH] drm/mm: revert "Break long searches in fragmented address spaces"

[Daniel Vetter]

On Tue, Mar 31, 2020 at 10:59:45AM +0200, Christian König wrote:
> A not so gentle ping, since this pretty much broke all TTM based drivers.
> 
> Could we revert this for now?

Always ack for revert.

Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>

Needs to go to drm-misc-next-fixes, and then maybe also ask for a
backmerge since the patch landed pre-split. Also ping Maarten to do
another pull request (there's other stuff in there already anyway).
-Daniel
> 
> Thanks,
> Christian.
> 
> Am 30.03.20 um 14:34 schrieb Christian König:
> > This reverts commit 7be1b9b8e9d1e9ef0342d2e001f44eec4030aa4d.
> > 
> > The drm_mm is supposed to work in atomic context, so calling schedule()
> > or in this case cond_resched() is illegal.
> > 
> > Signed-off-by: Christian König <christian.koenig at amd.com>
> > ---
> >   drivers/gpu/drm/drm_mm.c | 8 +-------
> >   1 file changed, 1 insertion(+), 7 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
> > index bc6e208949e8..8981abe8b7c9 100644
> > --- a/drivers/gpu/drm/drm_mm.c
> > +++ b/drivers/gpu/drm/drm_mm.c
> > @@ -45,7 +45,6 @@
> >   #include <linux/export.h>
> >   #include <linux/interval_tree_generic.h>
> >   #include <linux/seq_file.h>
> > -#include <linux/sched/signal.h>
> >   #include <linux/slab.h>
> >   #include <linux/stacktrace.h>
> > @@ -367,11 +366,6 @@ next_hole(struct drm_mm *mm,
> >   	  struct drm_mm_node *node,
> >   	  enum drm_mm_insert_mode mode)
> >   {
> > -	/* Searching is slow; check if we ran out of time/patience */
> > -	cond_resched();
> > -	if (fatal_signal_pending(current))
> > -		return NULL;
> > -
> >   	switch (mode) {
> >   	default:
> >   	case DRM_MM_INSERT_BEST:
> > @@ -563,7 +557,7 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm,
> >   		return 0;
> >   	}
> > -	return signal_pending(current) ? -ERESTARTSYS : -ENOSPC;
> > +	return -ENOSPC;
> >   }
> >   EXPORT_SYMBOL(drm_mm_insert_node_in_range);
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch