[RFC PATCH 02/18] mm/pgtable: convert ptdesc.pmd_huge_pte to ptdesc pointer

alexs
2024-07-30T06:43:24Z

folio/page.pmd_huge_pte is a pointer to pagetable descriptor: pgtable_t.
In most arch, it is a typedef of 'struct page *'. But we have ptdesc now,
tt's better to convert it to right one: struct ptdesc pointer.

Different from others, s390/sparc use typedef 'pte_t *' as pgtable_t, so
they need different cost in their arch.

Thanks for lkp found the build issue for s390/sparc, it fixed now.

Signed-off-by: Alex Shi <alexs@kernel.org>
Cc: linux-mm@kvack.org
Cc: sparclinux@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
---
arch/s390/mm/pgtable.c | 6 +++---
arch/sparc/mm/tlb.c | 6 +++---
include/linux/mm_types.h | 4 ++--
mm/pgtable-generic.c | 16 ++++++++--------
4 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 2c944bafb030..201d350abd1e 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -574,7 +574,7 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
INIT_LIST_HEAD(lh);
else
list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
- pmd_huge_pte(mm, pmdp) = pgtable;
+ pmd_huge_pte(mm, pmdp) = (struct ptdesc *)pgtable;
}

pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
@@ -586,12 +586,12 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
assert_spin_locked(pmd_lockptr(mm, pmdp));

/* FIFO */
- pgtable = pmd_huge_pte(mm, pmdp);
+ pgtable = (pte_t *)pmd_huge_pte(mm, pmdp);
lh = (struct list_head *) pgtable;
if (list_empty(lh))
pmd_huge_pte(mm, pmdp) = NULL;
else {
- pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
+ pmd_huge_pte(mm, pmdp) = (struct ptdesc *) lh->next;
list_del(lh);
}
ptep = (pte_t *) pgtable;
diff --git a/arch/sparc/mm/tlb.c b/arch/sparc/mm/tlb.c
index 8648a50afe88..903825b4c997 100644
--- a/arch/sparc/mm/tlb.c
+++ b/arch/sparc/mm/tlb.c
@@ -278,7 +278,7 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
INIT_LIST_HEAD(lh);
else
list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
- pmd_huge_pte(mm, pmdp) = pgtable;
+ pmd_huge_pte(mm, pmdp) = (struct ptdesc *)pgtable;
}

pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
@@ -289,12 +289,12 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
assert_spin_locked(&mm->page_table_lock);

/* FIFO */
- pgtable = pmd_huge_pte(mm, pmdp);
+ pgtable = (pte_t *)pmd_huge_pte(mm, pmdp);
lh = (struct list_head *) pgtable;
if (list_empty(lh))
pmd_huge_pte(mm, pmdp) = NULL;
else {
- pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
+ pmd_huge_pte(mm, pmdp) = (struct ptdesc *) lh->next;
list_del(lh);
}
pte_val(pgtable[0]) = 0;
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 485424979254..2e3eddf6edc9 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -462,7 +462,7 @@ struct ptdesc {
struct list_head pt_list;
struct {
unsigned long _pt_pad_1;
- pgtable_t pmd_huge_pte;
+ struct ptdesc *pmd_huge_pte;
};
};
unsigned long __page_mapping;
@@ -948,7 +948,7 @@ struct mm_struct {
struct mmu_notifier_subscriptions *notifier_subscriptions;
#endif
#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS
- pgtable_t pmd_huge_pte; /* protected by page_table_lock */
+ struct ptdesc *pmd_huge_pte; /* protected by page_table_lock */
#endif
#ifdef CONFIG_NUMA_BALANCING
/*
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 2ce714f1dd15..f34a8d115f5b 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -171,8 +171,8 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
if (!pmd_huge_pte(mm, pmdp))
INIT_LIST_HEAD(&pgtable->lru);
else
- list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->lru);
- pmd_huge_pte(mm, pmdp) = pgtable;
+ list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->pt_list);
+ pmd_huge_pte(mm, pmdp) = page_ptdesc(pgtable);
}
#endif

@@ -180,17 +180,17 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
/* no "address" argument so destroys page coloring of some arch */
pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
{
- pgtable_t pgtable;
+ struct ptdesc *ptdesc;

assert_spin_locked(pmd_lockptr(mm, pmdp));

/* FIFO */
- pgtable = pmd_huge_pte(mm, pmdp);
- pmd_huge_pte(mm, pmdp) = list_first_entry_or_null(&pgtable->lru,
- struct page, lru);
+ ptdesc = pmd_huge_pte(mm, pmdp);
+ pmd_huge_pte(mm, pmdp) = list_first_entry_or_null(&ptdesc->pt_list,
+ struct ptdesc, pt_list);
if (pmd_huge_pte(mm, pmdp))
- list_del(&pgtable->lru);
- return pgtable;
+ list_del(&ptdesc->pt_list);
+ return ptdesc_page(ptdesc);
}
#endif