| Message ID | 20200812063358.369514-5-aneesh.kumar@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/16] powerpc/mm: Add DEBUG_VM WARN for pmd_clear | expand |
On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote: > 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. This has not been a problem on architectures that do not define pxx_savedwrite() as they fallback on standard pxx_write() helpers. But ppc64 defines a fall back for pte_savedwrite() when !CONFIG_NUMA_BALANCING, which always returns false. Agreed, it makes sense to add CONFIG_NUMA_BALANCING check. But a simple runtime check will do as the functions are always visible/defined. if (!IS_ENABLED(CONFIG_NUMA_BALANCING)) return; > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> > --- > mm/debug_vm_pgtable.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c > index 679bb3d289a3..de8a62d0a931 100644 > --- a/mm/debug_vm_pgtable.c > +++ b/mm/debug_vm_pgtable.c > @@ -110,6 +110,7 @@ static void __init pte_advanced_tests(struct mm_struct *mm, > WARN_ON(pte_young(pte)); > } > > +#ifdef CONFIG_NUMA_BALANCING > static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot) > { > pte_t pte = pfn_pte(pfn, prot); > @@ -118,6 +119,8 @@ static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot) > WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte)))); > WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte)))); > } > +#endif > + > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot) > { > @@ -221,6 +224,7 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot) > WARN_ON(!pmd_none(pmd)); > } > > +#ifdef CONFIG_NUMA_BALANCING > static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot) > { > pmd_t pmd = pfn_pmd(pfn, prot); > @@ -229,6 +233,7 @@ static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot) > WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd)))); > WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd)))); > } > +#endif > > #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD > static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) > @@ -1005,8 +1010,10 @@ static int __init debug_vm_pgtable(void) > pmd_huge_tests(pmdp, pmd_aligned, prot); > pud_huge_tests(pudp, pud_aligned, prot); > > +#ifdef CONFIG_NUMA_BALANCING > pte_savedwrite_tests(pte_aligned, prot); > pmd_savedwrite_tests(pmd_aligned, prot); > +#endif BTW, config wrappers should be avoided at the call site. If and when needed a stub is defined for !CONFIG_XXX_XXX. > > pte_unmap_unlock(ptep, ptl); > >
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 679bb3d289a3..de8a62d0a931 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -110,6 +110,7 @@ static void __init pte_advanced_tests(struct mm_struct *mm, WARN_ON(pte_young(pte)); } +#ifdef CONFIG_NUMA_BALANCING static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot) { pte_t pte = pfn_pte(pfn, prot); @@ -118,6 +119,8 @@ static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot) WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte)))); WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte)))); } +#endif + #ifdef CONFIG_TRANSPARENT_HUGEPAGE static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot) { @@ -221,6 +224,7 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot) WARN_ON(!pmd_none(pmd)); } +#ifdef CONFIG_NUMA_BALANCING static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot) { pmd_t pmd = pfn_pmd(pfn, prot); @@ -229,6 +233,7 @@ static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot) WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd)))); WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd)))); } +#endif #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) @@ -1005,8 +1010,10 @@ static int __init debug_vm_pgtable(void) pmd_huge_tests(pmdp, pmd_aligned, prot); pud_huge_tests(pudp, pud_aligned, prot); +#ifdef CONFIG_NUMA_BALANCING pte_savedwrite_tests(pte_aligned, prot); pmd_savedwrite_tests(pmd_aligned, prot); +#endif pte_unmap_unlock(ptep, ptl);
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. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- mm/debug_vm_pgtable.c | 7 +++++++ 1 file changed, 7 insertions(+)