When pages are not 4K, PGDIR table is allocated with kmalloc(). In order to
optimise TLB handlers, aligned memory is needed. kmalloc() doesn't provide
aligned memory blocks, so lets use a kmem_cache pool instead.
Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr>
---
v2: changed to apply cleanly to linux-next (due to patch ab090dc)
arch/powerpc/include/asm/pgtable-ppc32.h | 4 ++++
arch/powerpc/mm/pgtable_32.c | 16 ++++++++++++++--
2 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h
b/arch/powerpc/include/asm/pgtable-ppc32.h
index c718bfd..affc703 100644
--- a/arch/powerpc/include/asm/pgtable-ppc32.h
+++ b/arch/powerpc/include/asm/pgtable-ppc32.h
@@ -341,10 +341,14 @@ static inline void __ptep_set_access_flags(pte_t *ptep,
pte_t entry)
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte)
>> 3 })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 3 })
+#ifndef CONFIG_PPC_4K_PAGES
+void pgtable_cache_init(void);
+#else
/*
* No page table caches to initialise
*/
#define pgtable_cache_init() do { } while (0)
+#endif
extern int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep,
pmd_t **pmdp);
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 50fad38..c06599f 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -73,13 +73,25 @@ extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
+#ifndef CONFIG_PPC_4K_PAGES
+static struct kmem_cache *pgtable_cache;
+
+void pgtable_cache_init(void)
+{
+ pgtable_cache = kmem_cache_create("PGDIR cache", 1 << PGDIR_ORDER,
+ 1 << PGDIR_ORDER, 0, NULL);
+ if (pgtable_cache == NULL)
+ panic("Couldn't allocate pgtable caches");
+}
+#endif
+
pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *ret;
/* pgdir take page or two with 4K pages and a page fraction otherwise */
#ifndef CONFIG_PPC_4K_PAGES
- ret = kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
+ ret = kmem_cache_alloc(pgtable_cache, GFP_KERNEL | __GFP_ZERO);
#else
ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
PGDIR_ORDER - PAGE_SHIFT);
@@ -90,7 +102,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
#ifndef CONFIG_PPC_4K_PAGES
- kfree((void *)pgd);
+ kmem_cache_free(pgtable_cache, (void *)pgd);
#else
free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
#endif
--
2.1.0
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