On Wed, Nov 12, 2014 at 03:22:41AM +0200, Kirill A. Shutemov wrote: > On Tue, Nov 11, 2014 at 04:49:13PM -0800, Andrew Morton wrote: > > On Tue, 11 Nov 2014 18:36:28 -0600 (CST) Christoph Lameter <cl at > > linux.com> wrote: > > > > > On Tue, 11 Nov 2014, Andrew Morton wrote: > > > > > > > There's no point in doing > > > > > > > > #define GFP_SLAB_BUG_MASK > > > > (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) > > > > > > > > because __GFP_DMA32|__GFP_HIGHMEM are already part of ~__GFP_BITS_MASK. > > > > > > ?? ~__GFP_BITS_MASK means bits 25 to 31 are set. > > > > > > __GFP_DMA32 is bit 2 and __GFP_HIGHMEM is bit 1. > > > > Ah, yes, OK. > > > > I suppose it's possible that __GFP_HIGHMEM was set. > > > > do_huge_pmd_anonymous_page > > ->pte_alloc_one > > ->alloc_pages(__userpte_alloc_gfp==__GFP_HIGHMEM) > > do_huge_pmd_anonymous_page > alloc_hugepage_vma > alloc_pages_vma(GFP_TRANSHUGE) > > GFP_TRANSHUGE contains GFP_HIGHUSER_MOVABLE, which has __GFP_HIGHMEM.
Hello, Kirill. BTW, why does GFP_TRANSHUGE have MOVABLE flag despite it isn't movable? After breaking hugepage, it could be movable, but, it may prevent CMA from working correctly until break. Thanks.
