Hi Sergey, On Wed, Nov 04, 2015 at 11:16:24AM +0900, Sergey Senozhatsky wrote: > Hi Minchan, > > On (11/04/15 10:25), Minchan Kim wrote: > [..] > >+static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, > >+ unsigned long end, struct mm_walk *walk) > >+ > ... > > + if (pmd_trans_unstable(pmd)) > > + return 0; > > I think it makes sense to update pmd_trans_unstable() and > pmd_none_or_trans_huge_or_clear_bad() comments in asm-generic/pgtable.h > Because they explicitly mention MADV_DONTNEED only. Just a thought. Hmm, When I read comments(but actually I don't understand it 100%), it says pmd disappearing from MADV_DONTNEED with mmap_sem read-side lock. But MADV_FREE doesn't remove the pmd. So, I don't understand what I should add comment. Please suggest if I am missing something. > > > > @@ -379,6 +502,14 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, > > return madvise_remove(vma, prev, start, end); > > case MADV_WILLNEED: > > return madvise_willneed(vma, prev, start, end); > > + case MADV_FREE: > > + /* > > + * XXX: In this implementation, MADV_FREE works like > ^^^^ > XXX What does it mean? > > > + * MADV_DONTNEED on swapless system or full swap. > > + */ > > + if (get_nr_swap_pages() > 0) > > + return madvise_free(vma, prev, start, end); > > + /* passthrough */ > > -ss -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>