diff mbox series

[v3,06/13] mm/debug_vm_pgtable/THP: Mark the pte entry huge before using set_pmd/pud_at

Message ID 20200827080438.315345-7-aneesh.kumar@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series mm/debug_vm_pgtable fixes | expand

Commit Message

Aneesh Kumar K.V Aug. 27, 2020, 8:04 a.m. UTC 
kernel expects entries to be marked huge before we use set_pmd_at()/set_pud_at().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
 mm/debug_vm_pgtable.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

Comments

Anshuman Khandual Sept. 1, 2020, 3:21 a.m. UTC | #1 
On 08/27/2020 01:34 PM, Aneesh Kumar K.V wrote:
> kernel expects entries to be marked huge before we use set_pmd_at()/set_pud_at().
> 
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> ---
>  mm/debug_vm_pgtable.c | 21 ++++++++++++---------
>  1 file changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
> index 5c0680836fe9..de83a20c1b30 100644
> --- a/mm/debug_vm_pgtable.c
> +++ b/mm/debug_vm_pgtable.c
> @@ -155,7 +155,7 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
>  				      unsigned long pfn, unsigned long vaddr,
>  				      pgprot_t prot)
>  {
> -	pmd_t pmd = pfn_pmd(pfn, prot);
> +	pmd_t pmd;
>  
>  	if (!has_transparent_hugepage())
>  		return;
> @@ -164,19 +164,19 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
>  	/* Align the address wrt HPAGE_PMD_SIZE */
>  	vaddr = (vaddr & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE;
>  
> -	pmd = pfn_pmd(pfn, prot);
> +	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
>  	set_pmd_at(mm, vaddr, pmdp, pmd);
>  	pmdp_set_wrprotect(mm, vaddr, pmdp);
>  	pmd = READ_ONCE(*pmdp);
>  	WARN_ON(pmd_write(pmd));
>  
> -	pmd = pfn_pmd(pfn, prot);
> +	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
>  	set_pmd_at(mm, vaddr, pmdp, pmd);
>  	pmdp_huge_get_and_clear(mm, vaddr, pmdp);
>  	pmd = READ_ONCE(*pmdp);
>  	WARN_ON(!pmd_none(pmd));
>  
> -	pmd = pfn_pmd(pfn, prot);
> +	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
>  	pmd = pmd_wrprotect(pmd);
>  	pmd = pmd_mkclean(pmd);
>  	set_pmd_at(mm, vaddr, pmdp, pmd);
> @@ -237,7 +237,7 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
>  
>  static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
>  {
> -	pmd_t pmd = pfn_pmd(pfn, prot);
> +	pmd_t pmd = pmd_mkhuge(pfn_pmd(pfn, prot));

There is no set_pmd_at() in this particular test, why change ?

>  
>  	if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
>  		return;
> @@ -277,7 +277,7 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
>  				      unsigned long pfn, unsigned long vaddr,
>  				      pgprot_t prot)
>  {
> -	pud_t pud = pfn_pud(pfn, prot);
> +	pud_t pud;
>  
>  	if (!has_transparent_hugepage())
>  		return;
> @@ -286,25 +286,28 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
>  	/* Align the address wrt HPAGE_PUD_SIZE */
>  	vaddr = (vaddr & HPAGE_PUD_MASK) + HPAGE_PUD_SIZE;
>  
> +	pud = pud_mkhuge(pfn_pud(pfn, prot));
>  	set_pud_at(mm, vaddr, pudp, pud);
>  	pudp_set_wrprotect(mm, vaddr, pudp);
>  	pud = READ_ONCE(*pudp);
>  	WARN_ON(pud_write(pud));
>  
>  #ifndef __PAGETABLE_PMD_FOLDED
> -	pud = pfn_pud(pfn, prot);
> +

Please drop the extra line here.

> +	pud = pud_mkhuge(pfn_pud(pfn, prot));
>  	set_pud_at(mm, vaddr, pudp, pud);
>  	pudp_huge_get_and_clear(mm, vaddr, pudp);
>  	pud = READ_ONCE(*pudp);
>  	WARN_ON(!pud_none(pud));
>  
> -	pud = pfn_pud(pfn, prot);
> +	pud = pud_mkhuge(pfn_pud(pfn, prot));
>  	set_pud_at(mm, vaddr, pudp, pud);
>  	pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
>  	pud = READ_ONCE(*pudp);
>  	WARN_ON(!pud_none(pud));
>  #endif /* __PAGETABLE_PMD_FOLDED */
> -	pud = pfn_pud(pfn, prot);
> +

Please drop the extra line here.

> +	pud = pud_mkhuge(pfn_pud(pfn, prot));
>  	pud = pud_wrprotect(pud);
>  	pud = pud_mkclean(pud);
>  	set_pud_at(mm, vaddr, pudp, pud);
>

There is a checkpatch.pl warning here.

WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#7: 
kernel expects entries to be marked huge before we use set_pmd_at()/set_pud_at().

total: 0 errors, 1 warnings, 77 lines checked
Aneesh Kumar K.V Sept. 1, 2020, 6:23 a.m. UTC | #2 
On 9/1/20 8:51 AM, Anshuman Khandual wrote:
> 
> 
> On 08/27/2020 01:34 PM, Aneesh Kumar K.V wrote:
>> kernel expects entries to be marked huge before we use set_pmd_at()/set_pud_at().
>>
>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
>> ---
>>   mm/debug_vm_pgtable.c | 21 ++++++++++++---------
>>   1 file changed, 12 insertions(+), 9 deletions(-)
>>
>> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
>> index 5c0680836fe9..de83a20c1b30 100644
>> --- a/mm/debug_vm_pgtable.c
>> +++ b/mm/debug_vm_pgtable.c
>> @@ -155,7 +155,7 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
>>   				      unsigned long pfn, unsigned long vaddr,
>>   				      pgprot_t prot)
>>   {
>> -	pmd_t pmd = pfn_pmd(pfn, prot);
>> +	pmd_t pmd;
>>   
>>   	if (!has_transparent_hugepage())
>>   		return;
>> @@ -164,19 +164,19 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
>>   	/* Align the address wrt HPAGE_PMD_SIZE */
>>   	vaddr = (vaddr & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE;
>>   
>> -	pmd = pfn_pmd(pfn, prot);
>> +	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
>>   	set_pmd_at(mm, vaddr, pmdp, pmd);
>>   	pmdp_set_wrprotect(mm, vaddr, pmdp);
>>   	pmd = READ_ONCE(*pmdp);
>>   	WARN_ON(pmd_write(pmd));
>>   
>> -	pmd = pfn_pmd(pfn, prot);
>> +	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
>>   	set_pmd_at(mm, vaddr, pmdp, pmd);
>>   	pmdp_huge_get_and_clear(mm, vaddr, pmdp);
>>   	pmd = READ_ONCE(*pmdp);
>>   	WARN_ON(!pmd_none(pmd));
>>   
>> -	pmd = pfn_pmd(pfn, prot);
>> +	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
>>   	pmd = pmd_wrprotect(pmd);
>>   	pmd = pmd_mkclean(pmd);
>>   	set_pmd_at(mm, vaddr, pmdp, pmd);
>> @@ -237,7 +237,7 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
>>   
>>   static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
>>   {
>> -	pmd_t pmd = pfn_pmd(pfn, prot);
>> +	pmd_t pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
> 
> There is no set_pmd_at() in this particular test, why change ?


because if you are building a hugepage you should use pmd_mkhuge(). That 
is what is setting _PAGE_PTE with this series. We don't make pfn_pmd set 
_PAGE_PTE


-aneesh
diff mbox series

Patch

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 5c0680836fe9..de83a20c1b30 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -155,7 +155,7 @@  static void __init pmd_advanced_tests(struct mm_struct *mm,
 				      unsigned long pfn, unsigned long vaddr,
 				      pgprot_t prot)
 {
-	pmd_t pmd = pfn_pmd(pfn, prot);
+	pmd_t pmd;
 
 	if (!has_transparent_hugepage())
 		return;
@@ -164,19 +164,19 @@  static void __init pmd_advanced_tests(struct mm_struct *mm,
 	/* Align the address wrt HPAGE_PMD_SIZE */
 	vaddr = (vaddr & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE;
 
-	pmd = pfn_pmd(pfn, prot);
+	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
 	set_pmd_at(mm, vaddr, pmdp, pmd);
 	pmdp_set_wrprotect(mm, vaddr, pmdp);
 	pmd = READ_ONCE(*pmdp);
 	WARN_ON(pmd_write(pmd));
 
-	pmd = pfn_pmd(pfn, prot);
+	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
 	set_pmd_at(mm, vaddr, pmdp, pmd);
 	pmdp_huge_get_and_clear(mm, vaddr, pmdp);
 	pmd = READ_ONCE(*pmdp);
 	WARN_ON(!pmd_none(pmd));
 
-	pmd = pfn_pmd(pfn, prot);
+	pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
 	pmd = pmd_wrprotect(pmd);
 	pmd = pmd_mkclean(pmd);
 	set_pmd_at(mm, vaddr, pmdp, pmd);
@@ -237,7 +237,7 @@  static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
 
 static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
 {
-	pmd_t pmd = pfn_pmd(pfn, prot);
+	pmd_t pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
 
 	if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
 		return;
@@ -277,7 +277,7 @@  static void __init pud_advanced_tests(struct mm_struct *mm,
 				      unsigned long pfn, unsigned long vaddr,
 				      pgprot_t prot)
 {
-	pud_t pud = pfn_pud(pfn, prot);
+	pud_t pud;
 
 	if (!has_transparent_hugepage())
 		return;
@@ -286,25 +286,28 @@  static void __init pud_advanced_tests(struct mm_struct *mm,
 	/* Align the address wrt HPAGE_PUD_SIZE */
 	vaddr = (vaddr & HPAGE_PUD_MASK) + HPAGE_PUD_SIZE;
 
+	pud = pud_mkhuge(pfn_pud(pfn, prot));
 	set_pud_at(mm, vaddr, pudp, pud);
 	pudp_set_wrprotect(mm, vaddr, pudp);
 	pud = READ_ONCE(*pudp);
 	WARN_ON(pud_write(pud));
 
 #ifndef __PAGETABLE_PMD_FOLDED
-	pud = pfn_pud(pfn, prot);
+
+	pud = pud_mkhuge(pfn_pud(pfn, prot));
 	set_pud_at(mm, vaddr, pudp, pud);
 	pudp_huge_get_and_clear(mm, vaddr, pudp);
 	pud = READ_ONCE(*pudp);
 	WARN_ON(!pud_none(pud));
 
-	pud = pfn_pud(pfn, prot);
+	pud = pud_mkhuge(pfn_pud(pfn, prot));
 	set_pud_at(mm, vaddr, pudp, pud);
 	pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
 	pud = READ_ONCE(*pudp);
 	WARN_ON(!pud_none(pud));
 #endif /* __PAGETABLE_PMD_FOLDED */
-	pud = pfn_pud(pfn, prot);
+
+	pud = pud_mkhuge(pfn_pud(pfn, prot));
 	pud = pud_wrprotect(pud);
 	pud = pud_mkclean(pud);
 	set_pud_at(mm, vaddr, pudp, pud);