drm/ttm: swap consecutive allocated cached pages v3

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

v2: use swap
v3: check if it's really the first allocated page

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Roger He <Hongbo.He@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Christian König 2017-12-04 11:17:54 +01:00 committed by Alex Deucher
parent 2bf257d662
commit 5ff7ec02f2

View File

@ -877,7 +877,7 @@ static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
#endif
struct list_head plist;
struct page *p = NULL;
unsigned count;
unsigned count, first;
int r;
/* No pool for cached pages */
@ -918,6 +918,7 @@ static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
}
#endif
first = i;
while (npages) {
p = alloc_page(gfp_flags);
if (!p) {
@ -925,6 +926,10 @@ static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
return -ENOMEM;
}
/* Swap the pages if we detect consecutive order */
if (i > first && pages[i - 1] == p - 1)
swap(p, pages[i - 1]);
pages[i++] = p;
--npages;
}