From 1b58a975be36994a572ae3b3fb3e023272bc299f Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Thu, 31 Jan 2019 18:30:22 +0800 Subject: [PATCH] powerpc/powernv/npu: Remove redundant change_pte() hook The change_pte() notifier was designed to use as a quick path to update secondary MMU PTEs on write permission changes or PFN changes. For KVM, it could reduce the vm-exits when vcpu faults on the pages that was touched up by KSM. It's not used to do cache invalidations, for example, if we see the notifier will be called before the real PTE update after all (please see set_pte_at_notify that set_pte_at was called later). All the necessary cache invalidation should all be done in invalidate_range() already. Signed-off-by: Peter Xu Reviewed-by: Andrea Arcangeli Reviewed-by: Alistair Popple Reviewed-by: Balbir Singh Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/powernv/npu-dma.c | 10 ---------- 1 file changed, 10 deletions(-) diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c index ccf186bb60ec..dc23d9d2a7d9 100644 --- a/arch/powerpc/platforms/powernv/npu-dma.c +++ b/arch/powerpc/platforms/powernv/npu-dma.c @@ -913,15 +913,6 @@ static void pnv_npu2_mn_release(struct mmu_notifier *mn, mmio_invalidate(npu_context, 0, ~0UL); } -static void pnv_npu2_mn_change_pte(struct mmu_notifier *mn, - struct mm_struct *mm, - unsigned long address, - pte_t pte) -{ - struct npu_context *npu_context = mn_to_npu_context(mn); - mmio_invalidate(npu_context, address, PAGE_SIZE); -} - static void pnv_npu2_mn_invalidate_range(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, unsigned long end) @@ -932,7 +923,6 @@ static void pnv_npu2_mn_invalidate_range(struct mmu_notifier *mn, static const struct mmu_notifier_ops nv_nmmu_notifier_ops = { .release = pnv_npu2_mn_release, - .change_pte = pnv_npu2_mn_change_pte, .invalidate_range = pnv_npu2_mn_invalidate_range, }; -- 2.45.2