[PATCH v6 09/12] mm/debug_vm_pgtable: Use struct pgtable_debug_args in PUD modifying tests

From: Gavin Shan
Date: Mon Aug 09 2021 - 05:28:20 EST


This uses struct pgtable_debug_args in PUD modifying tests. The allocated
huge page is used when set_pud_at() is used. The corresponding tests
are skipped if the huge page doesn't exist. Besides, the following unused
variables in debug_vm_pgtable() are dropped: @prot, @paddr, @pud_aligned.

Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
mm/debug_vm_pgtable.c | 126 ++++++++++++++++--------------------------
1 file changed, 48 insertions(+), 78 deletions(-)

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index abf778f729fd..4e453ae0f291 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -337,55 +337,56 @@ static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx)
WARN_ON(!pud_bad(pud_mkhuge(pud)));
}

-static void __init pud_advanced_tests(struct mm_struct *mm,
- struct vm_area_struct *vma, pud_t *pudp,
- unsigned long pfn, unsigned long vaddr,
- pgprot_t prot)
+static void __init pud_advanced_tests(struct pgtable_debug_args *args)
{
+ unsigned long vaddr = args->vaddr;
pud_t pud;

if (!has_transparent_hugepage())
return;

+ if (args->pud_pfn == ULONG_MAX)
+ return;
+
pr_debug("Validating PUD advanced\n");
/* Align the address wrt HPAGE_PUD_SIZE */
vaddr &= HPAGE_PUD_MASK;

- pud = pfn_pud(pfn, prot);
- set_pud_at(mm, vaddr, pudp, pud);
- pudp_set_wrprotect(mm, vaddr, pudp);
- pud = READ_ONCE(*pudp);
+ pud = pfn_pud(args->pud_pfn, args->page_prot);
+ set_pud_at(args->mm, vaddr, args->pudp, pud);
+ pudp_set_wrprotect(args->mm, vaddr, args->pudp);
+ pud = READ_ONCE(*args->pudp);
WARN_ON(pud_write(pud));

#ifndef __PAGETABLE_PMD_FOLDED
- pudp_huge_get_and_clear(mm, vaddr, pudp);
- pud = READ_ONCE(*pudp);
+ pudp_huge_get_and_clear(args->mm, vaddr, args->pudp);
+ pud = READ_ONCE(*args->pudp);
WARN_ON(!pud_none(pud));
#endif /* __PAGETABLE_PMD_FOLDED */
- pud = pfn_pud(pfn, prot);
+ pud = pfn_pud(args->pud_pfn, args->page_prot);
pud = pud_wrprotect(pud);
pud = pud_mkclean(pud);
- set_pud_at(mm, vaddr, pudp, pud);
+ set_pud_at(args->mm, vaddr, args->pudp, pud);
pud = pud_mkwrite(pud);
pud = pud_mkdirty(pud);
- pudp_set_access_flags(vma, vaddr, pudp, pud, 1);
- pud = READ_ONCE(*pudp);
+ pudp_set_access_flags(args->vma, vaddr, args->pudp, pud, 1);
+ pud = READ_ONCE(*args->pudp);
WARN_ON(!(pud_write(pud) && pud_dirty(pud)));

#ifndef __PAGETABLE_PMD_FOLDED
- pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
- pud = READ_ONCE(*pudp);
+ pudp_huge_get_and_clear_full(args->mm, vaddr, args->pudp, 1);
+ pud = READ_ONCE(*args->pudp);
WARN_ON(!pud_none(pud));
#endif /* __PAGETABLE_PMD_FOLDED */

- pud = pfn_pud(pfn, prot);
+ pud = pfn_pud(args->pud_pfn, args->page_prot);
pud = pud_mkyoung(pud);
- set_pud_at(mm, vaddr, pudp, pud);
- pudp_test_and_clear_young(vma, vaddr, pudp);
- pud = READ_ONCE(*pudp);
+ set_pud_at(args->mm, vaddr, args->pudp, pud);
+ pudp_test_and_clear_young(args->vma, vaddr, args->pudp);
+ pud = READ_ONCE(*args->pudp);
WARN_ON(pud_young(pud));

- pudp_huge_get_and_clear(mm, vaddr, pudp);
+ pudp_huge_get_and_clear(args->mm, vaddr, args->pudp);
}

static void __init pud_leaf_tests(struct pgtable_debug_args *args)
@@ -405,24 +406,14 @@ static void __init pud_leaf_tests(struct pgtable_debug_args *args)
}
#else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { }
-static void __init pud_advanced_tests(struct mm_struct *mm,
- struct vm_area_struct *vma, pud_t *pudp,
- unsigned long pfn, unsigned long vaddr,
- pgprot_t prot)
-{
-}
+static void __init pud_advanced_tests(struct pgtable_debug_args *args) { }
static void __init pud_leaf_tests(struct pgtable_debug_args *args) { }
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) { }
static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { }
static void __init pmd_advanced_tests(struct pgtable_debug_args *args) { }
-static void __init pud_advanced_tests(struct mm_struct *mm,
- struct vm_area_struct *vma, pud_t *pudp,
- unsigned long pfn, unsigned long vaddr,
- pgprot_t prot)
-{
-}
+static void __init pud_advanced_tests(struct pgtable_debug_args *args) { }
static void __init pmd_leaf_tests(struct pgtable_debug_args *args) { }
static void __init pud_leaf_tests(struct pgtable_debug_args *args) { }
static void __init pmd_savedwrite_tests(struct pgtable_debug_args *args) { }
@@ -448,11 +439,11 @@ static void __init pmd_huge_tests(struct pgtable_debug_args *args)
WARN_ON(!pmd_none(pmd));
}

-static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
+static void __init pud_huge_tests(struct pgtable_debug_args *args)
{
pud_t pud;

- if (!arch_vmap_pud_supported(prot))
+ if (!arch_vmap_pud_supported(args->page_prot))
return;

pr_debug("Validating PUD huge\n");
@@ -460,15 +451,15 @@ static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
* X86 defined pud_set_huge() verifies that the given
* PUD is not a populated non-leaf entry.
*/
- WRITE_ONCE(*pudp, __pud(0));
- WARN_ON(!pud_set_huge(pudp, __pfn_to_phys(pfn), prot));
- WARN_ON(!pud_clear_huge(pudp));
- pud = READ_ONCE(*pudp);
+ WRITE_ONCE(*args->pudp, __pud(0));
+ WARN_ON(!pud_set_huge(args->pudp, __pfn_to_phys(args->fixed_pud_pfn), args->page_prot));
+ WARN_ON(!pud_clear_huge(args->pudp));
+ pud = READ_ONCE(*args->pudp);
WARN_ON(!pud_none(pud));
}
#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
static void __init pmd_huge_tests(struct pgtable_debug_args *args) { }
-static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot) { }
+static void __init pud_huge_tests(struct pgtable_debug_args *args) { }
#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */

static void __init p4d_basic_tests(struct pgtable_debug_args *args)
@@ -490,27 +481,26 @@ static void __init pgd_basic_tests(struct pgtable_debug_args *args)
}

#ifndef __PAGETABLE_PUD_FOLDED
-static void __init pud_clear_tests(struct mm_struct *mm, pud_t *pudp)
+static void __init pud_clear_tests(struct pgtable_debug_args *args)
{
- pud_t pud = READ_ONCE(*pudp);
+ pud_t pud = READ_ONCE(*args->pudp);

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

pr_debug("Validating PUD clear\n");
pud = __pud(pud_val(pud) | RANDOM_ORVALUE);
- WRITE_ONCE(*pudp, pud);
- pud_clear(pudp);
- pud = READ_ONCE(*pudp);
+ WRITE_ONCE(*args->pudp, pud);
+ pud_clear(args->pudp);
+ pud = READ_ONCE(*args->pudp);
WARN_ON(!pud_none(pud));
}

-static void __init pud_populate_tests(struct mm_struct *mm, pud_t *pudp,
- pmd_t *pmdp)
+static void __init pud_populate_tests(struct pgtable_debug_args *args)
{
pud_t pud;

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

pr_debug("Validating PUD populate\n");
@@ -518,16 +508,13 @@ static void __init pud_populate_tests(struct mm_struct *mm, pud_t *pudp,
* This entry points to next level page table page.
* Hence this must not qualify as pud_bad().
*/
- pud_populate(mm, pudp, pmdp);
- pud = READ_ONCE(*pudp);
+ pud_populate(args->mm, args->pudp, args->start_pmdp);
+ pud = READ_ONCE(*args->pudp);
WARN_ON(pud_bad(pud));
}
#else /* !__PAGETABLE_PUD_FOLDED */
-static void __init pud_clear_tests(struct mm_struct *mm, pud_t *pudp) { }
-static void __init pud_populate_tests(struct mm_struct *mm, pud_t *pudp,
- pmd_t *pmdp)
-{
-}
+static void __init pud_clear_tests(struct pgtable_debug_args *args) { }
+static void __init pud_populate_tests(struct pgtable_debug_args *args) { }
#endif /* PAGETABLE_PUD_FOLDED */

#ifndef __PAGETABLE_P4D_FOLDED
@@ -1217,10 +1204,7 @@ static int __init debug_vm_pgtable(void)
pud_t *pudp, *saved_pudp;
pmd_t *pmdp, *saved_pmdp, pmd;
pgtable_t saved_ptep;
- pgprot_t prot;
- phys_addr_t paddr;
unsigned long vaddr;
- unsigned long pud_aligned;
spinlock_t *ptl = NULL;
int idx, ret;

@@ -1229,7 +1213,6 @@ static int __init debug_vm_pgtable(void)
if (ret)
return ret;

- prot = vm_get_page_prot(VMFLAGS);
vaddr = get_random_vaddr();
mm = mm_alloc();
if (!mm) {
@@ -1243,19 +1226,6 @@ static int __init debug_vm_pgtable(void)
return 1;
}

- /*
- * PFN for mapping at PTE level is determined from a standard kernel
- * text symbol. But pfns for higher page table levels are derived by
- * masking lower bits of this real pfn. These derived pfns might not
- * exist on the platform but that does not really matter as pfn_pxx()
- * helpers will still create appropriate entries for the test. This
- * helps avoid large memory block allocations to be used for mapping
- * at higher page table levels.
- */
- paddr = __pa_symbol(&start_kernel);
-
- pud_aligned = (paddr & PUD_MASK) >> PAGE_SHIFT;
-
pgdp = pgd_offset(mm, vaddr);
p4dp = p4d_alloc(mm, pgdp, vaddr);
pudp = pud_alloc(mm, p4dp, vaddr);
@@ -1348,11 +1318,11 @@ static int __init debug_vm_pgtable(void)
pmd_populate_tests(&args);
spin_unlock(ptl);

- ptl = pud_lock(mm, pudp);
- pud_clear_tests(mm, pudp);
- pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot);
- pud_huge_tests(pudp, pud_aligned, prot);
- pud_populate_tests(mm, pudp, saved_pmdp);
+ ptl = pud_lock(args.mm, args.pudp);
+ pud_clear_tests(&args);
+ pud_advanced_tests(&args);
+ pud_huge_tests(&args);
+ pud_populate_tests(&args);
spin_unlock(ptl);

spin_lock(&mm->page_table_lock);
--
2.23.0