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@xxxxxxxxxx>
---
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
