From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40m9761YvMzF14x for ; Wed, 16 May 2018 20:05:53 +1000 (AEST) Message-Id: In-Reply-To: References: From: Christophe Leroy Subject: [PATCH v2 13/14] powerpc/mm: Use pte_fragment_alloc() on 8xx To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , aneesh.kumar@linux.vnet.ibm.com Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Date: Wed, 16 May 2018 12:05:49 +0200 (CEST) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , In 16k page size mode, the 8xx need only 4k for a page table. This patch makes use of the pte_fragment functions in order to avoid wasting memory space Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/mmu-8xx.h | 4 +++ arch/powerpc/include/asm/nohash/32/pgalloc.h | 44 +++++++++++++++++++++++++++- arch/powerpc/include/asm/nohash/32/pgtable.h | 10 ++++++- arch/powerpc/mm/mmu_context_nohash.c | 4 +++ arch/powerpc/mm/pgtable.c | 10 ++++++- arch/powerpc/mm/pgtable_32.c | 12 ++++++++ arch/powerpc/platforms/Kconfig.cputype | 1 + 7 files changed, 82 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h index 193f53116c7a..4f4cb754afd8 100644 --- a/arch/powerpc/include/asm/mmu-8xx.h +++ b/arch/powerpc/include/asm/mmu-8xx.h @@ -190,6 +190,10 @@ typedef struct { struct slice_mask mask_8m; # endif #endif +#ifdef CONFIG_NEED_PTE_FRAG + /* for 4K PTE fragment support */ + void *pte_frag; +#endif } mm_context_t; #define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000) diff --git a/arch/powerpc/include/asm/nohash/32/pgalloc.h b/arch/powerpc/include/asm/nohash/32/pgalloc.h index 81c19d6460bd..d65b5f29008c 100644 --- a/arch/powerpc/include/asm/nohash/32/pgalloc.h +++ b/arch/powerpc/include/asm/nohash/32/pgalloc.h @@ -69,11 +69,22 @@ static inline void pmd_populate_kernel_g(struct mm_struct *mm, pmd_t *pmdp, static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t pte_page) { +#ifdef CONFIG_NEED_PTE_FRAG + *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT); +#else *pmdp = __pmd((page_to_pfn(pte_page) << PAGE_SHIFT) | _PMD_USER | _PMD_PRESENT); +#endif } +#ifdef CONFIG_NEED_PTE_FRAG +static inline pgtable_t pmd_pgtable(pmd_t pmd) +{ + return (pgtable_t)pmd_page_vaddr(pmd); +} +#else #define pmd_pgtable(pmd) pmd_page(pmd) +#endif #else static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, @@ -95,6 +106,32 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp, ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel_g(pmd, address))? \ NULL: pte_offset_kernel(pmd, address)) +#ifdef CONFIG_NEED_PTE_FRAG +extern pte_t *pte_fragment_alloc(struct mm_struct *, unsigned long, int); +extern void pte_fragment_free(unsigned long *, int); + +static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, + unsigned long address) +{ + return (pte_t *)pte_fragment_alloc(mm, address, 1); +} + +static inline pgtable_t pte_alloc_one(struct mm_struct *mm, + unsigned long address) +{ + return (pgtable_t)pte_fragment_alloc(mm, address, 0); +} + +static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) +{ + pte_fragment_free((unsigned long *)pte, 1); +} + +static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage) +{ + pte_fragment_free((unsigned long *)ptepage, 0); +} +#else extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr); extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr); @@ -108,11 +145,12 @@ static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage) pgtable_page_dtor(ptepage); __free_page(ptepage); } +#endif static inline void pgtable_free(void *table, unsigned index_size) { if (!index_size) { - free_page((unsigned long)table); + pte_free_kernel(NULL, table); } else { BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE); kmem_cache_free(PGT_CACHE(index_size), table); @@ -150,7 +188,11 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table, unsigned long address) { tlb_flush_pgtable(tlb, address); +#ifdef CONFIG_NEED_PTE_FRAG + pgtable_free_tlb(tlb, table, 0); +#else pgtable_page_dtor(table); pgtable_free_tlb(tlb, page_address(table), 0); +#endif } #endif /* _ASM_POWERPC_PGALLOC_32_H */ diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h index 5872d79360a9..ab5671e14fa1 100644 --- a/arch/powerpc/include/asm/nohash/32/pgtable.h +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h @@ -20,6 +20,9 @@ extern int icache_44x_need_flush; #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES) #define PTE_INDEX_SIZE (PTE_SHIFT - 2) +#define PTE_FRAG_NR 4 +#define PTE_FRAG_SIZE_SHIFT 12 +#define PTE_FRAG_SIZE (1UL << PTE_FRAG_SIZE_SHIFT) #else #define PTE_INDEX_SIZE PTE_SHIFT #endif @@ -319,7 +322,7 @@ static inline int pte_young(pte_t pte) */ #ifndef CONFIG_BOOKE #define pmd_page_vaddr(pmd) \ - ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK)) + ((unsigned long) __va(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1))) #define pmd_page(pmd) \ pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT) #else @@ -342,9 +345,14 @@ static inline int pte_young(pte_t pte) #define pte_offset_kernel(dir, addr) \ (pmd_bad(*(dir)) ? NULL : (pte_t *)pmd_page_vaddr(*(dir)) + \ pte_index(addr)) +#ifdef CONFIG_NEED_PTE_FRAG +#define pte_offset_map(dir, addr) pte_offset_kernel(dir, addr) +#define pte_unmap(pte) do {} while (0) +#else #define pte_offset_map(dir, addr) \ ((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr)) #define pte_unmap(pte) kunmap_atomic(pte) +#endif /* * Encode and decode a swap entry. diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c index e09228a9ad00..8b0ab33673e5 100644 --- a/arch/powerpc/mm/mmu_context_nohash.c +++ b/arch/powerpc/mm/mmu_context_nohash.c @@ -390,6 +390,9 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm) #endif mm->context.id = MMU_NO_CONTEXT; mm->context.active = 0; +#ifdef CONFIG_NEED_PTE_FRAG + mm->context.pte_frag = NULL; +#endif return 0; } @@ -418,6 +421,7 @@ void destroy_context(struct mm_struct *mm) nr_free_contexts++; } raw_spin_unlock_irqrestore(&context_lock, flags); + destroy_pagetable_page(mm); } #ifdef CONFIG_SMP diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index 2d34755ed727..96cc5aa73331 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -23,6 +23,7 @@ #include #include +#include #include #include #include @@ -320,10 +321,17 @@ static pte_t *__alloc_for_cache(struct mm_struct *mm, int kernel) return (pte_t *)ret; } -pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel) +__ref pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel) { pte_t *pte; + if (kernel && !slab_is_available()) { + pte = __va(memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE)); + if (pte) + memset(pte, 0, PTE_FRAG_SIZE); + + return pte; + } pte = get_from_cache(mm); if (pte) return pte; diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index 3aa0c78db95d..5c8737cf2945 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -40,6 +40,17 @@ extern char etext[], _stext[], _sinittext[], _einittext[]; +#ifdef CONFIG_NEED_PTE_FRAG +void pte_fragment_free(unsigned long *table, int kernel) +{ + struct page *page = virt_to_page(table); + if (put_page_testzero(page)) { + if (!kernel) + pgtable_page_dtor(page); + free_unref_page(page); + } +} +#else __ref pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) { pte_t *pte; @@ -69,6 +80,7 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address) } return ptepage; } +#endif #ifdef CONFIG_PPC_GUARDED_PAGE_IN_PMD int __pte_alloc_kernel_g(pmd_t *pmd, unsigned long address) diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 906f0ebd1e08..40cebb461bcb 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -340,6 +340,7 @@ config PPC_MM_SLICES config NEED_PTE_FRAG bool default y if PPC_BOOK3S_64 && PPC_64K_PAGES + default y if PPC_8xx && PPC_16K_PAGES default n config PPC_HAVE_PMU_SUPPORT -- 2.13.3