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-rw-r--r--mm/mprotect.c135
1 files changed, 111 insertions, 24 deletions
diff --git a/mm/mprotect.c b/mm/mprotect.c
index e8c3938db6f..3dca970367d 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -35,12 +35,16 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
}
#endif
-static void change_pte_range(struct mm_struct *mm, pmd_t *pmd,
+static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, unsigned long end, pgprot_t newprot,
- int dirty_accountable)
+ int dirty_accountable, int prot_numa, bool *ret_all_same_node)
{
+ struct mm_struct *mm = vma->vm_mm;
pte_t *pte, oldpte;
spinlock_t *ptl;
+ unsigned long pages = 0;
+ bool all_same_node = true;
+ int last_nid = -1;
pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
arch_enter_lazy_mmu_mode();
@@ -48,17 +52,43 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd,
oldpte = *pte;
if (pte_present(oldpte)) {
pte_t ptent;
+ bool updated = false;
ptent = ptep_modify_prot_start(mm, addr, pte);
- ptent = pte_modify(ptent, newprot);
+ if (!prot_numa) {
+ ptent = pte_modify(ptent, newprot);
+ updated = true;
+ } else {
+ struct page *page;
+
+ page = vm_normal_page(vma, addr, oldpte);
+ if (page) {
+ int this_nid = page_to_nid(page);
+ if (last_nid == -1)
+ last_nid = this_nid;
+ if (last_nid != this_nid)
+ all_same_node = false;
+
+ /* only check non-shared pages */
+ if (!pte_numa(oldpte) &&
+ page_mapcount(page) == 1) {
+ ptent = pte_mknuma(ptent);
+ updated = true;
+ }
+ }
+ }
/*
* Avoid taking write faults for pages we know to be
* dirty.
*/
- if (dirty_accountable && pte_dirty(ptent))
+ if (dirty_accountable && pte_dirty(ptent)) {
ptent = pte_mkwrite(ptent);
+ updated = true;
+ }
+ if (updated)
+ pages++;
ptep_modify_prot_commit(mm, addr, pte, ptent);
} else if (IS_ENABLED(CONFIG_MIGRATION) && !pte_file(oldpte)) {
swp_entry_t entry = pte_to_swp_entry(oldpte);
@@ -72,18 +102,40 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd,
set_pte_at(mm, addr, pte,
swp_entry_to_pte(entry));
}
+ pages++;
}
} while (pte++, addr += PAGE_SIZE, addr != end);
arch_leave_lazy_mmu_mode();
pte_unmap_unlock(pte - 1, ptl);
+
+ *ret_all_same_node = all_same_node;
+ return pages;
}
-static inline void change_pmd_range(struct vm_area_struct *vma, pud_t *pud,
+#ifdef CONFIG_NUMA_BALANCING
+static inline void change_pmd_protnuma(struct mm_struct *mm, unsigned long addr,
+ pmd_t *pmd)
+{
+ spin_lock(&mm->page_table_lock);
+ set_pmd_at(mm, addr & PMD_MASK, pmd, pmd_mknuma(*pmd));
+ spin_unlock(&mm->page_table_lock);
+}
+#else
+static inline void change_pmd_protnuma(struct mm_struct *mm, unsigned long addr,
+ pmd_t *pmd)
+{
+ BUG();
+}
+#endif /* CONFIG_NUMA_BALANCING */
+
+static inline unsigned long change_pmd_range(struct vm_area_struct *vma, pud_t *pud,
unsigned long addr, unsigned long end, pgprot_t newprot,
- int dirty_accountable)
+ int dirty_accountable, int prot_numa)
{
pmd_t *pmd;
unsigned long next;
+ unsigned long pages = 0;
+ bool all_same_node;
pmd = pmd_offset(pud, addr);
do {
@@ -91,42 +143,59 @@ static inline void change_pmd_range(struct vm_area_struct *vma, pud_t *pud,
if (pmd_trans_huge(*pmd)) {
if (next - addr != HPAGE_PMD_SIZE)
split_huge_page_pmd(vma, addr, pmd);
- else if (change_huge_pmd(vma, pmd, addr, newprot))
+ else if (change_huge_pmd(vma, pmd, addr, newprot, prot_numa)) {
+ pages += HPAGE_PMD_NR;
continue;
+ }
/* fall through */
}
if (pmd_none_or_clear_bad(pmd))
continue;
- change_pte_range(vma->vm_mm, pmd, addr, next, newprot,
- dirty_accountable);
+ pages += change_pte_range(vma, pmd, addr, next, newprot,
+ dirty_accountable, prot_numa, &all_same_node);
+
+ /*
+ * If we are changing protections for NUMA hinting faults then
+ * set pmd_numa if the examined pages were all on the same
+ * node. This allows a regular PMD to be handled as one fault
+ * and effectively batches the taking of the PTL
+ */
+ if (prot_numa && all_same_node)
+ change_pmd_protnuma(vma->vm_mm, addr, pmd);
} while (pmd++, addr = next, addr != end);
+
+ return pages;
}
-static inline void change_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
+static inline unsigned long change_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
unsigned long addr, unsigned long end, pgprot_t newprot,
- int dirty_accountable)
+ int dirty_accountable, int prot_numa)
{
pud_t *pud;
unsigned long next;
+ unsigned long pages = 0;
pud = pud_offset(pgd, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
continue;
- change_pmd_range(vma, pud, addr, next, newprot,
- dirty_accountable);
+ pages += change_pmd_range(vma, pud, addr, next, newprot,
+ dirty_accountable, prot_numa);
} while (pud++, addr = next, addr != end);
+
+ return pages;
}
-static void change_protection(struct vm_area_struct *vma,
+static unsigned long change_protection_range(struct vm_area_struct *vma,
unsigned long addr, unsigned long end, pgprot_t newprot,
- int dirty_accountable)
+ int dirty_accountable, int prot_numa)
{
struct mm_struct *mm = vma->vm_mm;
pgd_t *pgd;
unsigned long next;
unsigned long start = addr;
+ unsigned long pages = 0;
BUG_ON(addr >= end);
pgd = pgd_offset(mm, addr);
@@ -135,10 +204,32 @@ static void change_protection(struct vm_area_struct *vma,
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- change_pud_range(vma, pgd, addr, next, newprot,
- dirty_accountable);
+ pages += change_pud_range(vma, pgd, addr, next, newprot,
+ dirty_accountable, prot_numa);
} while (pgd++, addr = next, addr != end);
- flush_tlb_range(vma, start, end);
+
+ /* Only flush the TLB if we actually modified any entries: */
+ if (pages)
+ flush_tlb_range(vma, start, end);
+
+ return pages;
+}
+
+unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end, pgprot_t newprot,
+ int dirty_accountable, int prot_numa)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ unsigned long pages;
+
+ mmu_notifier_invalidate_range_start(mm, start, end);
+ if (is_vm_hugetlb_page(vma))
+ pages = hugetlb_change_protection(vma, start, end, newprot);
+ else
+ pages = change_protection_range(vma, start, end, newprot, dirty_accountable, prot_numa);
+ mmu_notifier_invalidate_range_end(mm, start, end);
+
+ return pages;
}
int
@@ -213,12 +304,8 @@ success:
dirty_accountable = 1;
}
- mmu_notifier_invalidate_range_start(mm, start, end);
- if (is_vm_hugetlb_page(vma))
- hugetlb_change_protection(vma, start, end, vma->vm_page_prot);
- else
- change_protection(vma, start, end, vma->vm_page_prot, dirty_accountable);
- mmu_notifier_invalidate_range_end(mm, start, end);
+ change_protection(vma, start, end, vma->vm_page_prot, dirty_accountable, 0);
+
vm_stat_account(mm, oldflags, vma->vm_file, -nrpages);
vm_stat_account(mm, newflags, vma->vm_file, nrpages);
perf_event_mmap(vma);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-19 02:15:23 +0000