Re: [PATCH 2/4] mm: mremap: use flush_pmd_tlb_range() in move_normal_pmd()
From: Catalin Marinas <catalin.marinas@arm.com>
Date: 2023-07-31 11:05:43
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On Mon, Jul 31, 2023 at 03:48:27PM +0800, Kefeng Wang wrote:
quoted hunk ↗ jump to hunk
Archs may need to do special things when flushing thp tlb, so use the more applicable flush_pud_tlb_range() instead of flush_tlb_range(). Fixes: 2c91bd4a4e2e ("mm: speed up mremap by 20x on large regions") Signed-off-by: Kefeng Wang <redacted> --- mm/mremap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/mm/mremap.c b/mm/mremap.c index 11e06e4ab33b..1883205fa22b 100644 --- a/mm/mremap.c +++ b/mm/mremap.c@@ -284,7 +284,7 @@ static bool move_normal_pmd(struct vm_area_struct *vma, unsigned long old_addr, VM_BUG_ON(!pmd_none(*new_pmd)); pmd_populate(mm, new_pmd, pmd_pgtable(pmd)); - flush_tlb_range(vma, old_addr, old_addr + PMD_SIZE); + flush_pmd_tlb_range(vma, old_addr, old_addr + PMD_SIZE);
I don't think that's correct for arm64. The assumption in the flush_p*d_tlb_range() was that they are called only for block mappings at that p*d level (and we use FEAT_TTL on arm64 indicating that the leaf level is level 2 for pmd, 1 for pud). IIUC move_normal_pmd() is only called for table pmds which would have a leaf level of 3 (the pte). Same for the next patch doing the equivalent for the pud. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel