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

From: Yan Zhao
Date: Thu Aug 10 2023 - 05:27:44 EST


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@xxxxxxxxx>
---
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