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> --- 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 543bb8e..d323e8b 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -346,10 +346,14 @@ 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); diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index cf11342..730dc2d 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 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev