diff mbox series

[v3,11/12] mm/debug_vm_pgtable: Remove unused code

Message ID 20210719130613.334901-12-gshan@redhat.com (mailing list archive)
State New
Headers show
Series mm/debug_vm_pgtable: Enhancements | expand

Commit Message

Gavin Shan July 19, 2021, 1:06 p.m. UTC
The variables used by old implementation isn't needed as we switched
to "struct pgtable_debug_args". Lets remove them and related code in
debug_vm_pgtable().

Signed-off-by: Gavin Shan <gshan@redhat.com>
---
 mm/debug_vm_pgtable.c | 54 -------------------------------------------
 1 file changed, 54 deletions(-)

Comments

Anshuman Khandual July 22, 2021, 4:51 a.m. UTC | #1
Small nit for the subject line.

s/Remove unused code/Remove unused page table debug elements/

On 7/19/21 6:36 PM, Gavin Shan wrote:
> The variables used by old implementation isn't needed as we switched
> to "struct pgtable_debug_args". Lets remove them and related code in
> debug_vm_pgtable().
> 
> Signed-off-by: Gavin Shan <gshan@redhat.com>
> ---
>  mm/debug_vm_pgtable.c | 54 -------------------------------------------
>  1 file changed, 54 deletions(-)
> 
> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
> index 5ebacc940b68..4f7bf1c9724a 100644
> --- a/mm/debug_vm_pgtable.c
> +++ b/mm/debug_vm_pgtable.c
> @@ -1124,14 +1124,6 @@ static int __init init_args(struct pgtable_debug_args *args)
>  static int __init debug_vm_pgtable(void)
>  {
>  	struct pgtable_debug_args args;
> -	struct vm_area_struct *vma;
> -	struct mm_struct *mm;
> -	pgd_t *pgdp;
> -	p4d_t *p4dp;
> -	pud_t *pudp;
> -	pmd_t *pmdp, *saved_pmdp, pmd;
> -	pgtable_t saved_ptep;
> -	unsigned long vaddr;
>  	spinlock_t *ptl = NULL;
>  	int idx, ret;
>  
> @@ -1140,41 +1132,6 @@ static int __init debug_vm_pgtable(void)
>  	if (ret)
>  		return ret;
>  
> -	vaddr = get_random_vaddr();
> -	mm = mm_alloc();
> -	if (!mm) {
> -		pr_err("mm_struct allocation failed\n");
> -		return 1;
> -	}
> -
> -	vma = vm_area_alloc(mm);
> -	if (!vma) {
> -		pr_err("vma allocation failed\n");
> -		return 1;
> -	}
> -
> -	pgdp = pgd_offset(mm, vaddr);
> -	p4dp = p4d_alloc(mm, pgdp, vaddr);
> -	pudp = pud_alloc(mm, p4dp, vaddr);
> -	pmdp = pmd_alloc(mm, pudp, vaddr);
> -	/*
> -	 * Allocate pgtable_t
> -	 */
> -	if (pte_alloc(mm, pmdp)) {
> -		pr_err("pgtable allocation failed\n");
> -		return 1;
> -	}
> -
> -	/*
> -	 * Save all the page table page addresses as the page table
> -	 * entries will be used for testing with random or garbage
> -	 * values. These saved addresses will be used for freeing
> -	 * page table pages.
> -	 */

Please move this comment as is to the right place inside init_args()
in the first patch itself. If possible all comments should be moved
during the first patch and just the code gets dropped here.

> -	pmd = READ_ONCE(*pmdp);
> -	saved_pmdp = pmd_offset(pudp, 0UL);
> -	saved_ptep = pmd_pgtable(pmd);
> -
>  	/*
>  	 * Iterate over the protection_map[] to make sure that all
>  	 * the basic page table transformation validations just hold
> @@ -1256,17 +1213,6 @@ static int __init debug_vm_pgtable(void)
>  	pgd_populate_tests(&args);
>  	spin_unlock(&(args.mm->page_table_lock));
>  
> -	p4d_free(mm, p4d_offset(pgdp, 0UL));
> -	pud_free(mm, pud_offset(p4dp, 0UL));
> -	pmd_free(mm, saved_pmdp);
> -	pte_free(mm, saved_ptep);
> -
> -	vm_area_free(vma);
> -	mm_dec_nr_puds(mm);
> -	mm_dec_nr_pmds(mm);
> -	mm_dec_nr_ptes(mm);
> -	mmdrop(mm);
> -
>  	destroy_args(&args);
>  	return 0;
>  }
>
Gavin Shan July 22, 2021, 6:53 a.m. UTC | #2
Hi Anshuman,

On 7/22/21 2:51 PM, Anshuman Khandual wrote:
> Small nit for the subject line.
> 
> s/Remove unused code/Remove unused page table debug elements/
> 

Ok. Will apply the replacement in v4, thanks!

> On 7/19/21 6:36 PM, Gavin Shan wrote:
>> The variables used by old implementation isn't needed as we switched
>> to "struct pgtable_debug_args". Lets remove them and related code in
>> debug_vm_pgtable().
>>
>> Signed-off-by: Gavin Shan <gshan@redhat.com>
>> ---
>>   mm/debug_vm_pgtable.c | 54 -------------------------------------------
>>   1 file changed, 54 deletions(-)
>>
>> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
>> index 5ebacc940b68..4f7bf1c9724a 100644
>> --- a/mm/debug_vm_pgtable.c
>> +++ b/mm/debug_vm_pgtable.c
>> @@ -1124,14 +1124,6 @@ static int __init init_args(struct pgtable_debug_args *args)
>>   static int __init debug_vm_pgtable(void)
>>   {
>>   	struct pgtable_debug_args args;
>> -	struct vm_area_struct *vma;
>> -	struct mm_struct *mm;
>> -	pgd_t *pgdp;
>> -	p4d_t *p4dp;
>> -	pud_t *pudp;
>> -	pmd_t *pmdp, *saved_pmdp, pmd;
>> -	pgtable_t saved_ptep;
>> -	unsigned long vaddr;
>>   	spinlock_t *ptl = NULL;
>>   	int idx, ret;
>>   
>> @@ -1140,41 +1132,6 @@ static int __init debug_vm_pgtable(void)
>>   	if (ret)
>>   		return ret;
>>   
>> -	vaddr = get_random_vaddr();
>> -	mm = mm_alloc();
>> -	if (!mm) {
>> -		pr_err("mm_struct allocation failed\n");
>> -		return 1;
>> -	}
>> -
>> -	vma = vm_area_alloc(mm);
>> -	if (!vma) {
>> -		pr_err("vma allocation failed\n");
>> -		return 1;
>> -	}
>> -
>> -	pgdp = pgd_offset(mm, vaddr);
>> -	p4dp = p4d_alloc(mm, pgdp, vaddr);
>> -	pudp = pud_alloc(mm, p4dp, vaddr);
>> -	pmdp = pmd_alloc(mm, pudp, vaddr);
>> -	/*
>> -	 * Allocate pgtable_t
>> -	 */
>> -	if (pte_alloc(mm, pmdp)) {
>> -		pr_err("pgtable allocation failed\n");
>> -		return 1;
>> -	}
>> -
>> -	/*
>> -	 * Save all the page table page addresses as the page table
>> -	 * entries will be used for testing with random or garbage
>> -	 * values. These saved addresses will be used for freeing
>> -	 * page table pages.
>> -	 */
> 
> Please move this comment as is to the right place inside init_args()
> in the first patch itself. If possible all comments should be moved
> during the first patch and just the code gets dropped here.
> 

In PATCH[v3 01/12], We already had the comments in init_args() as below:

        /*
         * The above page table entries will be modified. Lets save the
         * page table entries so that they can be released when the tests
         * are completed.
         */


>> -	pmd = READ_ONCE(*pmdp);
>> -	saved_pmdp = pmd_offset(pudp, 0UL);
>> -	saved_ptep = pmd_pgtable(pmd);
>> -
>>   	/*
>>   	 * Iterate over the protection_map[] to make sure that all
>>   	 * the basic page table transformation validations just hold
>> @@ -1256,17 +1213,6 @@ static int __init debug_vm_pgtable(void)
>>   	pgd_populate_tests(&args);
>>   	spin_unlock(&(args.mm->page_table_lock));
>>   
>> -	p4d_free(mm, p4d_offset(pgdp, 0UL));
>> -	pud_free(mm, pud_offset(p4dp, 0UL));
>> -	pmd_free(mm, saved_pmdp);
>> -	pte_free(mm, saved_ptep);
>> -
>> -	vm_area_free(vma);
>> -	mm_dec_nr_puds(mm);
>> -	mm_dec_nr_pmds(mm);
>> -	mm_dec_nr_ptes(mm);
>> -	mmdrop(mm);
>> -
>>   	destroy_args(&args);
>>   	return 0;
>>   }
>>

Thanks,
Gavin
diff mbox series

Patch

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 5ebacc940b68..4f7bf1c9724a 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -1124,14 +1124,6 @@  static int __init init_args(struct pgtable_debug_args *args)
 static int __init debug_vm_pgtable(void)
 {
 	struct pgtable_debug_args args;
-	struct vm_area_struct *vma;
-	struct mm_struct *mm;
-	pgd_t *pgdp;
-	p4d_t *p4dp;
-	pud_t *pudp;
-	pmd_t *pmdp, *saved_pmdp, pmd;
-	pgtable_t saved_ptep;
-	unsigned long vaddr;
 	spinlock_t *ptl = NULL;
 	int idx, ret;
 
@@ -1140,41 +1132,6 @@  static int __init debug_vm_pgtable(void)
 	if (ret)
 		return ret;
 
-	vaddr = get_random_vaddr();
-	mm = mm_alloc();
-	if (!mm) {
-		pr_err("mm_struct allocation failed\n");
-		return 1;
-	}
-
-	vma = vm_area_alloc(mm);
-	if (!vma) {
-		pr_err("vma allocation failed\n");
-		return 1;
-	}
-
-	pgdp = pgd_offset(mm, vaddr);
-	p4dp = p4d_alloc(mm, pgdp, vaddr);
-	pudp = pud_alloc(mm, p4dp, vaddr);
-	pmdp = pmd_alloc(mm, pudp, vaddr);
-	/*
-	 * Allocate pgtable_t
-	 */
-	if (pte_alloc(mm, pmdp)) {
-		pr_err("pgtable allocation failed\n");
-		return 1;
-	}
-
-	/*
-	 * Save all the page table page addresses as the page table
-	 * entries will be used for testing with random or garbage
-	 * values. These saved addresses will be used for freeing
-	 * page table pages.
-	 */
-	pmd = READ_ONCE(*pmdp);
-	saved_pmdp = pmd_offset(pudp, 0UL);
-	saved_ptep = pmd_pgtable(pmd);
-
 	/*
 	 * Iterate over the protection_map[] to make sure that all
 	 * the basic page table transformation validations just hold
@@ -1256,17 +1213,6 @@  static int __init debug_vm_pgtable(void)
 	pgd_populate_tests(&args);
 	spin_unlock(&(args.mm->page_table_lock));
 
-	p4d_free(mm, p4d_offset(pgdp, 0UL));
-	pud_free(mm, pud_offset(p4dp, 0UL));
-	pmd_free(mm, saved_pmdp);
-	pte_free(mm, saved_ptep);
-
-	vm_area_free(vma);
-	mm_dec_nr_puds(mm);
-	mm_dec_nr_pmds(mm);
-	mm_dec_nr_ptes(mm);
-	mmdrop(mm);
-
 	destroy_args(&args);
 	return 0;
 }