powerpc32: Use kmem_cache memory for PGDIR

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.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
This commit is contained in:
LEROY Christophe 2015-01-20 10:57:34 +01:00 committed by Scott Wood
parent 5ddb75cee5
commit ce67f5d0a0
2 changed files with 18 additions and 2 deletions

View file

@ -347,10 +347,14 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
#define pte_to_pgoff(pte) (pte_val(pte) >> 3)
#define pgoff_to_pte(off) ((pte_t) { ((off) << 3) | _PAGE_FILE })
#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);

View file

@ -72,13 +72,25 @@ 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);
@ -89,7 +101,7 @@ 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