From f820e2805c7acb157a78438d07e47f4fc57fe679 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Thu, 14 Nov 2013 14:31:50 -0800 Subject: [PATCH] xtensa: use buddy allocator for PTE table At the moment xtensa uses slab allocator for PTE table. It doesn't work with enabled split page table lock: slab uses page->slab_cache and page->first_page for its pages. These fields share stroage with page->ptl. Signed-off-by: Kirill A. Shutemov Cc: Chris Zankel Acked-by: Max Filippov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/xtensa/include/asm/pgalloc.h | 20 ++++++++++++-------- arch/xtensa/include/asm/pgtable.h | 3 +-- arch/xtensa/mm/mmu.c | 20 -------------------- 3 files changed, 13 insertions(+), 30 deletions(-) diff --git a/arch/xtensa/include/asm/pgalloc.h b/arch/xtensa/include/asm/pgalloc.h index b8774f1..d38eb92 100644 --- a/arch/xtensa/include/asm/pgalloc.h +++ b/arch/xtensa/include/asm/pgalloc.h @@ -38,14 +38,18 @@ static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) free_page((unsigned long)pgd); } -/* Use a slab cache for the pte pages (see also sparc64 implementation) */ - -extern struct kmem_cache *pgtable_cache; - static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) { - return kmem_cache_alloc(pgtable_cache, GFP_KERNEL|__GFP_REPEAT); + pte_t *ptep; + int i; + + ptep = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT); + if (!ptep) + return NULL; + for (i = 0; i < 1024; i++) + pte_clear(NULL, 0, ptep + i); + return ptep; } static inline pgtable_t pte_alloc_one(struct mm_struct *mm, @@ -59,7 +63,7 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm, return NULL; page = virt_to_page(pte); if (!pgtable_page_ctor(page)) { - kmem_cache_free(pgtable_cache, pte); + __free_page(page); return NULL; } return page; @@ -67,13 +71,13 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm, static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) { - kmem_cache_free(pgtable_cache, pte); + free_page((unsigned long)pte); } static inline void pte_free(struct mm_struct *mm, pgtable_t pte) { pgtable_page_dtor(pte); - kmem_cache_free(pgtable_cache, page_address(pte)); + __free_page(pte); } #define pmd_pgtable(pmd) pmd_page(pmd) diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h index 0fdf5d0..2164462 100644 --- a/arch/xtensa/include/asm/pgtable.h +++ b/arch/xtensa/include/asm/pgtable.h @@ -220,12 +220,11 @@ extern unsigned long empty_zero_page[1024]; #ifdef CONFIG_MMU extern pgd_t swapper_pg_dir[PAGE_SIZE/sizeof(pgd_t)]; extern void paging_init(void); -extern void pgtable_cache_init(void); #else # define swapper_pg_dir NULL static inline void paging_init(void) { } -static inline void pgtable_cache_init(void) { } #endif +static inline void pgtable_cache_init(void) { } /* * The pmd contains the kernel virtual address of the pte page. diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c index a107757..c43771c 100644 --- a/arch/xtensa/mm/mmu.c +++ b/arch/xtensa/mm/mmu.c @@ -50,23 +50,3 @@ void __init init_mmu(void) */ set_ptevaddr_register(PGTABLE_START); } - -struct kmem_cache *pgtable_cache __read_mostly; - -static void pgd_ctor(void *addr) -{ - pte_t *ptep = (pte_t *)addr; - int i; - - for (i = 0; i < 1024; i++, ptep++) - pte_clear(NULL, 0, ptep); - -} - -void __init pgtable_cache_init(void) -{ - pgtable_cache = kmem_cache_create("pgd", - PAGE_SIZE, PAGE_SIZE, - SLAB_HWCACHE_ALIGN, - pgd_ctor); -} -- 2.7.4