On Tue, 21 Nov 2006, Mel Gorman wrote:
On Tue, 21 Nov 2006, Christoph Lameter wrote:
Are GFP_HIGHUSER allocations always movable? It would reduce the size ofNo, they aren't. Page tables allocated with HIGHPTE are currently not movable
the patch if this would be added to GFP_HIGHUSER.
for example. A number of drivers (infiniband for example) also use
__GFP_HIGHMEM that are not movable.
HIGHPTE with __GFP_USER set? This is a page table page right?
pte_alloc_one does currently not set GFP_USER:
struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
struct page *pte;
#ifdef CONFIG_HIGHPTE
pte =
alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT|__GFP_ZERO, 0);
#else
pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
#endif
return pte;
}
How does infiniband insure that page migration does not move those pages?