From: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> Subject: mm/debug_vm_pgtable/savedwrite: enable savedwrite test with CONFIG_NUMA_BALANCING Saved write support was added to track the write bit of a pte after marking the pte protnone. This was done so that AUTONUMA can convert a write pte to protnone and still track the old write bit. When converting it back we set the pte write bit correctly thereby avoiding a write fault again. Hence enable the test only when CONFIG_NUMA_BALANCING is enabled and use protnone protflags. Link: https://lkml.kernel.org/r/20200902114222.181353-6-aneesh.kumar@xxxxxxxxxxxxx Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/debug_vm_pgtable.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) --- a/mm/debug_vm_pgtable.c~mm-debug_vm_pgtable-savedwrite-enable-savedwrite-test-with-config_numa_balancing +++ a/mm/debug_vm_pgtable.c @@ -119,10 +119,14 @@ static void __init pte_savedwrite_tests( { pte_t pte = pfn_pte(pfn, prot); + if (!IS_ENABLED(CONFIG_NUMA_BALANCING)) + return; + pr_debug("Validating PTE saved write\n"); WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte)))); WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte)))); } + #ifdef CONFIG_TRANSPARENT_HUGEPAGE static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot) { @@ -234,6 +238,9 @@ static void __init pmd_savedwrite_tests( { pmd_t pmd = pfn_pmd(pfn, prot); + if (!IS_ENABLED(CONFIG_NUMA_BALANCING)) + return; + pr_debug("Validating PMD saved write\n"); WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd)))); WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd)))); @@ -1019,8 +1026,8 @@ static int __init debug_vm_pgtable(void) pmd_huge_tests(pmdp, pmd_aligned, prot); pud_huge_tests(pudp, pud_aligned, prot); - pte_savedwrite_tests(pte_aligned, prot); - pmd_savedwrite_tests(pmd_aligned, prot); + pte_savedwrite_tests(pte_aligned, protnone); + pmd_savedwrite_tests(pmd_aligned, protnone); pte_unmap_unlock(ptep, ptl); _
