[PATCH v6 10/12] mm/debug_vm_pgtable: Use struct pgtable_debug_args in PGD and P4D modifying tests

From: Gavin Shan
Date: Mon Aug 09 2021 - 05:28:25 EST


This uses struct pgtable_debug_args in PGD/P4D modifying tests. No
allocated huge page is used in these tests. Besides, the unused
variable @saved_p4dp and @saved_pudp are dropped.

Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
mm/debug_vm_pgtable.c | 86 +++++++++++++++++++------------------------
1 file changed, 38 insertions(+), 48 deletions(-)

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 4e453ae0f291..9e932ae9f158 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -518,27 +518,26 @@ static void __init pud_populate_tests(struct pgtable_debug_args *args) { }
#endif /* PAGETABLE_PUD_FOLDED */

#ifndef __PAGETABLE_P4D_FOLDED
-static void __init p4d_clear_tests(struct mm_struct *mm, p4d_t *p4dp)
+static void __init p4d_clear_tests(struct pgtable_debug_args *args)
{
- p4d_t p4d = READ_ONCE(*p4dp);
+ p4d_t p4d = READ_ONCE(*args->p4dp);

- if (mm_pud_folded(mm))
+ if (mm_pud_folded(args->mm))
return;

pr_debug("Validating P4D clear\n");
p4d = __p4d(p4d_val(p4d) | RANDOM_ORVALUE);
- WRITE_ONCE(*p4dp, p4d);
- p4d_clear(p4dp);
- p4d = READ_ONCE(*p4dp);
+ WRITE_ONCE(*args->p4dp, p4d);
+ p4d_clear(args->p4dp);
+ p4d = READ_ONCE(*args->p4dp);
WARN_ON(!p4d_none(p4d));
}

-static void __init p4d_populate_tests(struct mm_struct *mm, p4d_t *p4dp,
- pud_t *pudp)
+static void __init p4d_populate_tests(struct pgtable_debug_args *args)
{
p4d_t p4d;

- if (mm_pud_folded(mm))
+ if (mm_pud_folded(args->mm))
return;

pr_debug("Validating P4D populate\n");
@@ -546,34 +545,33 @@ static void __init p4d_populate_tests(struct mm_struct *mm, p4d_t *p4dp,
* This entry points to next level page table page.
* Hence this must not qualify as p4d_bad().
*/
- pud_clear(pudp);
- p4d_clear(p4dp);
- p4d_populate(mm, p4dp, pudp);
- p4d = READ_ONCE(*p4dp);
+ pud_clear(args->pudp);
+ p4d_clear(args->p4dp);
+ p4d_populate(args->mm, args->p4dp, args->start_pudp);
+ p4d = READ_ONCE(*args->p4dp);
WARN_ON(p4d_bad(p4d));
}

-static void __init pgd_clear_tests(struct mm_struct *mm, pgd_t *pgdp)
+static void __init pgd_clear_tests(struct pgtable_debug_args *args)
{
- pgd_t pgd = READ_ONCE(*pgdp);
+ pgd_t pgd = READ_ONCE(*(args->pgdp));

- if (mm_p4d_folded(mm))
+ if (mm_p4d_folded(args->mm))
return;

pr_debug("Validating PGD clear\n");
pgd = __pgd(pgd_val(pgd) | RANDOM_ORVALUE);
- WRITE_ONCE(*pgdp, pgd);
- pgd_clear(pgdp);
- pgd = READ_ONCE(*pgdp);
+ WRITE_ONCE(*args->pgdp, pgd);
+ pgd_clear(args->pgdp);
+ pgd = READ_ONCE(*args->pgdp);
WARN_ON(!pgd_none(pgd));
}

-static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp,
- p4d_t *p4dp)
+static void __init pgd_populate_tests(struct pgtable_debug_args *args)
{
pgd_t pgd;

- if (mm_p4d_folded(mm))
+ if (mm_p4d_folded(args->mm))
return;

pr_debug("Validating PGD populate\n");
@@ -581,23 +579,17 @@ static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp,
* This entry points to next level page table page.
* Hence this must not qualify as pgd_bad().
*/
- p4d_clear(p4dp);
- pgd_clear(pgdp);
- pgd_populate(mm, pgdp, p4dp);
- pgd = READ_ONCE(*pgdp);
+ p4d_clear(args->p4dp);
+ pgd_clear(args->pgdp);
+ pgd_populate(args->mm, args->pgdp, args->start_p4dp);
+ pgd = READ_ONCE(*args->pgdp);
WARN_ON(pgd_bad(pgd));
}
#else /* !__PAGETABLE_P4D_FOLDED */
-static void __init p4d_clear_tests(struct mm_struct *mm, p4d_t *p4dp) { }
-static void __init pgd_clear_tests(struct mm_struct *mm, pgd_t *pgdp) { }
-static void __init p4d_populate_tests(struct mm_struct *mm, p4d_t *p4dp,
- pud_t *pudp)
-{
-}
-static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp,
- p4d_t *p4dp)
-{
-}
+static void __init p4d_clear_tests(struct pgtable_debug_args *args) { }
+static void __init pgd_clear_tests(struct pgtable_debug_args *args) { }
+static void __init p4d_populate_tests(struct pgtable_debug_args *args) { }
+static void __init pgd_populate_tests(struct pgtable_debug_args *args) { }
#endif /* PAGETABLE_P4D_FOLDED */

static void __init pte_clear_tests(struct pgtable_debug_args *args)
@@ -1200,8 +1192,8 @@ static int __init debug_vm_pgtable(void)
struct vm_area_struct *vma;
struct mm_struct *mm;
pgd_t *pgdp;
- p4d_t *p4dp, *saved_p4dp;
- pud_t *pudp, *saved_pudp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp, *saved_pmdp, pmd;
pgtable_t saved_ptep;
unsigned long vaddr;
@@ -1245,8 +1237,6 @@ static int __init debug_vm_pgtable(void)
* page table pages.
*/
pmd = READ_ONCE(*pmdp);
- saved_p4dp = p4d_offset(pgdp, 0UL);
- saved_pudp = pud_offset(p4dp, 0UL);
saved_pmdp = pmd_offset(pudp, 0UL);
saved_ptep = pmd_pgtable(pmd);

@@ -1325,15 +1315,15 @@ static int __init debug_vm_pgtable(void)
pud_populate_tests(&args);
spin_unlock(ptl);

- spin_lock(&mm->page_table_lock);
- p4d_clear_tests(mm, p4dp);
- pgd_clear_tests(mm, pgdp);
- p4d_populate_tests(mm, p4dp, saved_pudp);
- pgd_populate_tests(mm, pgdp, saved_p4dp);
- spin_unlock(&mm->page_table_lock);
+ spin_lock(&(args.mm->page_table_lock));
+ p4d_clear_tests(&args);
+ pgd_clear_tests(&args);
+ p4d_populate_tests(&args);
+ pgd_populate_tests(&args);
+ spin_unlock(&(args.mm->page_table_lock));

- p4d_free(mm, saved_p4dp);
- pud_free(mm, saved_pudp);
+ p4d_free(mm, p4d_offset(pgdp, 0UL));
+ pud_free(mm, pud_offset(p4dp, 0UL));
pmd_free(mm, saved_pmdp);
pte_free(mm, saved_ptep);

--
2.23.0