[PATCH v9 09/20] powerpc/mm: enable the use of page table cache of order 0

From: Christophe Leroy
Date: Thu Nov 29 2018 - 09:07:08 EST


hugepages uses a cache of order 0. Lets allow page tables
of order 0 in the common part in order to avoid open coding
in hugetlb

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/include/asm/book3s/32/pgalloc.h | 5 +----
arch/powerpc/include/asm/book3s/64/pgalloc.h | 5 +----
arch/powerpc/include/asm/nohash/32/pgalloc.h | 5 +----
arch/powerpc/include/asm/nohash/64/pgalloc.h | 5 +----
arch/powerpc/mm/init-common.c | 6 +++---
5 files changed, 7 insertions(+), 19 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/32/pgalloc.h b/arch/powerpc/include/asm/book3s/32/pgalloc.h
index 0f58e5b9dbe7..b5b955eb2fb7 100644
--- a/arch/powerpc/include/asm/book3s/32/pgalloc.h
+++ b/arch/powerpc/include/asm/book3s/32/pgalloc.h
@@ -25,10 +25,7 @@
extern void __bad_pte(pmd_t *pmd);

extern struct kmem_cache *pgtable_cache[];
-#define PGT_CACHE(shift) ({ \
- BUG_ON(!(shift)); \
- pgtable_cache[(shift) - 1]; \
- })
+#define PGT_CACHE(shift) pgtable_cache[shift]

static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
diff --git a/arch/powerpc/include/asm/book3s/64/pgalloc.h b/arch/powerpc/include/asm/book3s/64/pgalloc.h
index f949dd90af9b..4aba625389c4 100644
--- a/arch/powerpc/include/asm/book3s/64/pgalloc.h
+++ b/arch/powerpc/include/asm/book3s/64/pgalloc.h
@@ -37,10 +37,7 @@ extern struct vmemmap_backing *vmemmap_list;
#define MAX_PGTABLE_INDEX_SIZE 0xf

extern struct kmem_cache *pgtable_cache[];
-#define PGT_CACHE(shift) ({ \
- BUG_ON(!(shift)); \
- pgtable_cache[(shift) - 1]; \
- })
+#define PGT_CACHE(shift) pgtable_cache[shift]

extern pte_t *pte_fragment_alloc(struct mm_struct *, unsigned long, int);
extern pmd_t *pmd_fragment_alloc(struct mm_struct *, unsigned long);
diff --git a/arch/powerpc/include/asm/nohash/32/pgalloc.h b/arch/powerpc/include/asm/nohash/32/pgalloc.h
index 7e234582dce5..17963951bdb0 100644
--- a/arch/powerpc/include/asm/nohash/32/pgalloc.h
+++ b/arch/powerpc/include/asm/nohash/32/pgalloc.h
@@ -25,10 +25,7 @@
extern void __bad_pte(pmd_t *pmd);

extern struct kmem_cache *pgtable_cache[];
-#define PGT_CACHE(shift) ({ \
- BUG_ON(!(shift)); \
- pgtable_cache[(shift) - 1]; \
- })
+#define PGT_CACHE(shift) pgtable_cache[shift]

static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
diff --git a/arch/powerpc/include/asm/nohash/64/pgalloc.h b/arch/powerpc/include/asm/nohash/64/pgalloc.h
index e2d62d033708..e95eb499a174 100644
--- a/arch/powerpc/include/asm/nohash/64/pgalloc.h
+++ b/arch/powerpc/include/asm/nohash/64/pgalloc.h
@@ -36,10 +36,7 @@ extern struct vmemmap_backing *vmemmap_list;
#define MAX_PGTABLE_INDEX_SIZE 0xf

extern struct kmem_cache *pgtable_cache[];
-#define PGT_CACHE(shift) ({ \
- BUG_ON(!(shift)); \
- pgtable_cache[(shift) - 1]; \
- })
+#define PGT_CACHE(shift) pgtable_cache[shift]

static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c
index 2b656e67f2ea..41190f2b60c2 100644
--- a/arch/powerpc/mm/init-common.c
+++ b/arch/powerpc/mm/init-common.c
@@ -40,7 +40,7 @@ static void pmd_ctor(void *addr)
memset(addr, 0, PMD_TABLE_SIZE);
}

-struct kmem_cache *pgtable_cache[MAX_PGTABLE_INDEX_SIZE];
+struct kmem_cache *pgtable_cache[MAX_PGTABLE_INDEX_SIZE + 1];
EXPORT_SYMBOL_GPL(pgtable_cache); /* used by kvm_hv module */

/*
@@ -71,7 +71,7 @@ void pgtable_cache_add(unsigned shift, void (*ctor)(void *))
* moment, gcc doesn't seem to recognize is_power_of_2 as a
* constant expression, so so much for that. */
BUG_ON(!is_power_of_2(minalign));
- BUG_ON((shift < 1) || (shift > MAX_PGTABLE_INDEX_SIZE));
+ BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);

if (PGT_CACHE(shift))
return; /* Already have a cache of this size */
@@ -83,7 +83,7 @@ void pgtable_cache_add(unsigned shift, void (*ctor)(void *))
panic("Could not allocate pgtable cache for order %d", shift);

kfree(name);
- pgtable_cache[shift - 1] = new;
+ pgtable_cache[shift] = new;

pr_debug("Allocated pgtable cache for order %d\n", shift);
}
--
2.13.3