Re: [PATCH 1/2] drm/ttm: swap consecutive allocated cached pages

On 2017-12-04 12:42 PM, Christian König wrote:

When we detect consecutive allocation of pages swap them to avoid accidentally freeing them as huge page.

Signed-off-by: Christian König christian.koenig@amd.com

drivers/gpu/drm/ttm/ttm_page_alloc.c | 8 ++++++++ 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c index c82d94cbbabc..60401350a01a 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c @@ -921,6 +921,14 @@ static int ttm_get_pages(struct page **pages, unsigned npages, int flags, return -ENOMEM; }

• 	/* Swap the pages if we detect consecutive order */
  

• 	if (i && pages[i - 1] == p - 1) {
  

• 		struct page *tmp = p;
  

• 		p = pages[i - 1];
  

• 		pages[i - 1] = tmp;
  

• 	}
  

Should be (something like):

if (i && pages[i - 1] == p - 1) swap(pages[i - 1], p);