From 369258ce41c6d7663a7b6d509356fecad577378d Mon Sep 17 00:00:00 2001 From: Mike Kravetz Date: Mon, 14 Nov 2022 15:55:07 -0800 Subject: hugetlb: remove duplicate mmu notifications The common hugetlb unmap routine __unmap_hugepage_range performs mmu notification calls. However, in the case where __unmap_hugepage_range is called via __unmap_hugepage_range_final, mmu notification calls are performed earlier in other calling routines. Remove mmu notification calls from __unmap_hugepage_range. Add notification calls to the only other caller: unmap_hugepage_range. unmap_hugepage_range is called for truncation and hole punch, so change notification type from UNMAP to CLEAR as this is more appropriate. Link: https://lkml.kernel.org/r/20221114235507.294320-4-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz Suggested-by: Peter Xu Cc: Wei Chen Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Matthew Wilcox Cc: Mina Almasry Cc: Nadav Amit Cc: Naoya Horiguchi Cc: Rik van Riel Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- mm/hugetlb.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 4f1338d82aab..3fd4570fb8b0 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5076,7 +5076,6 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct struct page *page; struct hstate *h = hstate_vma(vma); unsigned long sz = huge_page_size(h); - struct mmu_notifier_range range; unsigned long last_addr_mask; bool force_flush = false; @@ -5091,13 +5090,6 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct tlb_change_page_size(tlb, sz); tlb_start_vma(tlb, vma); - /* - * If sharing possible, alert mmu notifiers of worst case. - */ - mmu_notifier_range_init(&range, MMU_NOTIFY_UNMAP, 0, vma, mm, start, - end); - adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); - mmu_notifier_invalidate_range_start(&range); last_addr_mask = hugetlb_mask_last_page(h); address = start; for (; address < end; address += sz) { @@ -5182,7 +5174,6 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct if (ref_page) break; } - mmu_notifier_invalidate_range_end(&range); tlb_end_vma(tlb, vma); /* @@ -5210,6 +5201,7 @@ void __unmap_hugepage_range_final(struct mmu_gather *tlb, hugetlb_vma_lock_write(vma); i_mmap_lock_write(vma->vm_file->f_mapping); + /* mmu notification performed in caller */ __unmap_hugepage_range(tlb, vma, start, end, ref_page, zap_flags); if (zap_flags & ZAP_FLAG_UNMAP) { /* final unmap */ @@ -5234,10 +5226,18 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, struct page *ref_page, zap_flags_t zap_flags) { + struct mmu_notifier_range range; struct mmu_gather tlb; + mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm, + start, end); + adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); + mmu_notifier_invalidate_range_start(&range); tlb_gather_mmu(&tlb, vma->vm_mm); + __unmap_hugepage_range(&tlb, vma, start, end, ref_page, zap_flags); + + mmu_notifier_invalidate_range_end(&range); tlb_finish_mmu(&tlb); } -- cgit v1.2.3