[RFC PATCH v2 4/5] mm/autonuma: call .numa_protect() when page is protected for NUMA migrate

From: Yan Zhao <yan.y.zhao@intel.com>
To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: pbonzini@redhat.com, seanjc@google.com, mike.kravetz@oracle.com,
	apopple@nvidia.com, jgg@nvidia.com, rppt@kernel.org,
	akpm@linux-foundation.org, kevin.tian@intel.com,
	david@redhat.com, Yan Zhao <yan.y.zhao@intel.com>
Subject: [RFC PATCH v2 4/5] mm/autonuma: call .numa_protect() when page is protected for NUMA migrate
Date: Thu, 10 Aug 2023 17:00:48 +0800	[thread overview]
Message-ID: <20230810090048.26184-1-yan.y.zhao@intel.com> (raw)
In-Reply-To: <20230810085636.25914-1-yan.y.zhao@intel.com>

Call mmu notifier's callback .numa_protect() in change_pmd_range() when
a page is ensured to be protected by PROT_NONE for NUMA migration purpose.

Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
---
 mm/huge_memory.c | 1 +
 mm/mprotect.c    | 1 +
 2 files changed, 2 insertions(+)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a71cf686e3b2..8ae56507da12 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1892,6 +1892,7 @@ int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 		if (sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING &&
 		    !toptier)
 			xchg_page_access_time(page, jiffies_to_msecs(jiffies));
+		mmu_notifier_numa_protect(vma->vm_mm, addr, addr + PMD_SIZE);
 	}
 	/*
 	 * In case prot_numa, we are under mmap_read_lock(mm). It's critical
diff --git a/mm/mprotect.c b/mm/mprotect.c
index a1f63df34b86..c401814b2992 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -164,6 +164,7 @@ static long change_pte_range(struct mmu_gather *tlb,
 				    !toptier)
 					xchg_page_access_time(page,
 						jiffies_to_msecs(jiffies));
+				mmu_notifier_numa_protect(vma->vm_mm, addr, addr + PAGE_SIZE);
 			}
 
 			oldpte = ptep_modify_prot_start(vma, addr, pte);
-- 
2.17.1

