On Fri 24-08-18 11:08:24, Mike Kravetz wrote:
On 08/24/2018 01:41 AM, Michal Hocko wrote:
On Thu 23-08-18 13:59:16, Mike Kravetz wrote:
Acked-by: Michal Hocko mhocko@suse.com
One nit below.
[...]
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3103099f64fd..a73c5728e961 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4548,6 +4548,9 @@ static unsigned long page_table_shareable(struct vm_area_struct *svma, return saddr; } +#define _range_in_vma(vma, start, end) \
- ((vma)->vm_start <= (start) && (end) <= (vma)->vm_end)
static inline please. Macros and potential side effects on given arguments are just not worth the risk. I also think this is something for more general use. We have that pattern at many places. So I would stick that to linux/mm.h
Thanks Michal,
Here is an updated patch which does as you suggest above.
[...]
@@ -1409,6 +1419,32 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte); address = pvmw.address;
if (PageHuge(page)) {
if (huge_pmd_unshare(mm, &address, pvmw.pte)) {
/*
* huge_pmd_unshare unmapped an entire PMD
* page. There is no way of knowing exactly
* which PMDs may be cached for this mm, so
* we must flush them all. start/end were
* already adjusted above to cover this range.
*/
flush_cache_range(vma, start, end);
flush_tlb_range(vma, start, end);
mmu_notifier_invalidate_range(mm, start, end);
/*
* The ref count of the PMD page was dropped
* which is part of the way map counting
* is done for shared PMDs. Return 'true'
* here. When there is no other sharing,
* huge_pmd_unshare returns false and we will
* unmap the actual page and drop map count
* to zero.
*/
page_vma_mapped_walk_done(&pvmw);
break;
}
This still calls into notifier while holding the ptl lock. Either I am missing something or the invalidation is broken in this loop (not also for other invalidations).