[PATCH 1/1] drm/ttm: Account for kernel allocations in kernel zone only

[Thomas Hellstrom]

On Mon, 2019-02-25 at 14:20 +0000, Koenig, Christian wrote:
> Am 23.02.19 um 00:19 schrieb Kuehling, Felix:
> > Don't account for them in other zones such as dma32. The kernel
> > page
> > allocator has its own heuristics to avoid exhausting special zones
> > for regular kernel allocations.
> > 
> > Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com>
> > CC: thellstrom at vmware.com
> > CC: christian.koenig at amd.com
> 
> Reviewed-by: Christian König <christian.koenig at amd.com>

Hmm,

So actually with this patch we theoretically still can exhaust the
DMA32 zone by first performing kernel allocations that DO spare a
number of DMA32 pages  according to the kernel allocator heuristics,
and then populate TTM buffers with DMA32 pages only.

However, since vmwgfx bo's don't request DMA32 pages, we're OK with
this, and it's really up to Christian to decide. So:

Acked-by: Thomas Hellstrom <thellstrom at vmware.com>

Thanks,
Thomas








> 
> > ---
> >   drivers/gpu/drm/ttm/ttm_memory.c | 6 +++---
> >   1 file changed, 3 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/ttm/ttm_memory.c
> > b/drivers/gpu/drm/ttm/ttm_memory.c
> > index f1567c3..90d1e24 100644
> > --- a/drivers/gpu/drm/ttm/ttm_memory.c
> > +++ b/drivers/gpu/drm/ttm/ttm_memory.c
> > @@ -522,7 +522,7 @@ static void ttm_mem_global_free_zone(struct
> > ttm_mem_global *glob,
> >   void ttm_mem_global_free(struct ttm_mem_global *glob,
> >   			 uint64_t amount)
> >   {
> > -	return ttm_mem_global_free_zone(glob, NULL, amount);
> > +	return ttm_mem_global_free_zone(glob, glob->zone_kernel,
> > amount);
> >   }
> >   EXPORT_SYMBOL(ttm_mem_global_free);
> >   
> > @@ -621,10 +621,10 @@ int ttm_mem_global_alloc(struct
> > ttm_mem_global *glob, uint64_t memory,
> >   {
> >   	/**
> >   	 * Normal allocations of kernel memory are registered in
> > -	 * all zones.
> > +	 * the kernel zone.
> >   	 */
> >   
> > -	return ttm_mem_global_alloc_zone(glob, NULL, memory, ctx);
> > +	return ttm_mem_global_alloc_zone(glob, glob->zone_kernel,
> > memory, ctx);
> >   }
> >   EXPORT_SYMBOL(ttm_mem_global_alloc);
> >