[V1,09/11] powerpc/mm: Implement helpers for pagetable fragment support at PMD level

Message ID	20180416112724.9677-11-aneesh.kumar@linux.ibm.com (mailing list archive)
State	Accepted
Commit	8a6c697b993974eeb05f540fb0ff2515346dbefd
Headers	show Return-Path: <linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org> Gateway: Authorized Use Only! Violators will be prosecuted for <linuxppc-dev@lists.ozlabs.org> from <aneesh.kumar@linux.ibm.com>; Mon, 16 Apr 2018 07:28:17 -0400 Gateway: Authorized Use Only! Violators will be prosecuted; Mon, 16 Apr 2018 07:28:14 -0400 From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> To: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au Subject: [PATCH V1 09/11] powerpc/mm: Implement helpers for pagetable fragment support at PMD level Date: Mon, 16 Apr 2018 16:57:22 +0530 In-Reply-To: <20180416112724.9677-1-aneesh.kumar@linux.ibm.com> References: <20180416112724.9677-1-aneesh.kumar@linux.ibm.com> Message-Id: <20180416112724.9677-11-aneesh.kumar@linux.ibm.com> Precedence: list Cc: linuxppc-dev@lists.ozlabs.org, "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" <linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org>
Series	powerpc/mm/book3s64: Support for split pmd ptlock \| expand [V1,00/11] powerpc/mm/book3s64: Support for split pmd ptlock [V1,01/11] powerpc/mm/book3s64: Move book3s64 code to pgtable-book3s64 [V1,02/11] powerpc/kvm: Switch kvm pmd allocator to custom allocator [V1,03/11] powerpc/mm: Use pmd_lockptr instead of opencoding it [V1,04/11] powerpc/mm: Rename pte fragment functions [V1,05/11] powerpc/mm/book3e/64: Remove unsupported 64Kpage size from 64bit booke [V1,06/11] powerpc/mm/nohash: Remove pte fragment dependency from nohash [V1,07/11] powerpc/mm/book3s64/4k: Switch 4k pagesize config to use pagetable fragment [V1,08/11] powerpc/book3s64/mm: Simplify the rcu callback for page table free [V1,09/11] powerpc/mm: Implement helpers for pagetable fragment support at PMD level [V1,10/11] powerpc/mm: Use page fragments for allocation page table at PMD level [V1,11/11] powerpc/book3s64: Enable split pmd ptlock.

diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h index 00c4db2a7682..9a3798660cef 100644 --- a/arch/powerpc/include/asm/book3s/64/hash-4k.h +++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h @@ -42,6 +42,8 @@ /* 8 bytes per each pte entry */ #define H_PTE_FRAG_SIZE_SHIFT (H_PTE_INDEX_SIZE + 3) #define H_PTE_FRAG_NR (PAGE_SIZE >> H_PTE_FRAG_SIZE_SHIFT) +#define H_PMD_FRAG_SIZE_SHIFT (H_PMD_INDEX_SIZE + 3) +#define H_PMD_FRAG_NR (PAGE_SIZE >> H_PMD_FRAG_SIZE_SHIFT) /* memory key bits, only 8 keys supported */ #define H_PTE_PKEY_BIT0 0 diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h index cc82745355b3..c81793d47af9 100644 --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h @@ -46,6 +46,13 @@ #define H_PTE_FRAG_SIZE_SHIFT (H_PTE_INDEX_SIZE + 3 + 1) #define H_PTE_FRAG_NR (PAGE_SIZE >> H_PTE_FRAG_SIZE_SHIFT) +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE) +#define H_PMD_FRAG_SIZE_SHIFT (H_PMD_INDEX_SIZE + 3 + 1) +#else +#define H_PMD_FRAG_SIZE_SHIFT (H_PMD_INDEX_SIZE + 3) +#endif +#define H_PMD_FRAG_NR (PAGE_SIZE >> H_PMD_FRAG_SIZE_SHIFT) + #ifndef __ASSEMBLY__ #include <asm/errno.h> diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h index fde7803a2261..9c8c669a6b6a 100644 --- a/arch/powerpc/include/asm/book3s/64/mmu.h +++ b/arch/powerpc/include/asm/book3s/64/mmu.h @@ -138,6 +138,7 @@ typedef struct { * pagetable fragment support */ void *pte_frag; + void *pmd_frag; #ifdef CONFIG_SPAPR_TCE_IOMMU struct list_head iommu_group_mem_list; #endif diff --git a/arch/powerpc/include/asm/book3s/64/pgalloc.h b/arch/powerpc/include/asm/book3s/64/pgalloc.h index ed313b8d3fac..005f400cbf30 100644 --- a/arch/powerpc/include/asm/book3s/64/pgalloc.h +++ b/arch/powerpc/include/asm/book3s/64/pgalloc.h @@ -42,7 +42,9 @@ extern struct kmem_cache *pgtable_cache[]; }) extern pte_t *pte_fragment_alloc(struct mm_struct *, unsigned long, int); +extern pmd_t *pmd_fragment_alloc(struct mm_struct *, unsigned long); extern void pte_fragment_free(unsigned long *, int); +extern void pmd_fragment_free(unsigned long *); extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift); #ifdef CONFIG_SMP extern void __tlb_remove_table(void *_table); diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 9462bc18806c..c9db19512b3c 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -246,6 +246,12 @@ extern unsigned long __pte_frag_size_shift; #define PTE_FRAG_SIZE_SHIFT __pte_frag_size_shift #define PTE_FRAG_SIZE (1UL << PTE_FRAG_SIZE_SHIFT) +extern unsigned long __pmd_frag_nr; +#define PMD_FRAG_NR __pmd_frag_nr +extern unsigned long __pmd_frag_size_shift; +#define PMD_FRAG_SIZE_SHIFT __pmd_frag_size_shift +#define PMD_FRAG_SIZE (1UL << PMD_FRAG_SIZE_SHIFT) + #define PTRS_PER_PTE (1 << PTE_INDEX_SIZE) #define PTRS_PER_PMD (1 << PMD_INDEX_SIZE) #define PTRS_PER_PUD (1 << PUD_INDEX_SIZE) diff --git a/arch/powerpc/include/asm/book3s/64/radix-4k.h b/arch/powerpc/include/asm/book3s/64/radix-4k.h index ca366ec86310..863c3e8286fb 100644 --- a/arch/powerpc/include/asm/book3s/64/radix-4k.h +++ b/arch/powerpc/include/asm/book3s/64/radix-4k.h @@ -15,4 +15,7 @@ #define RADIX_PTE_FRAG_SIZE_SHIFT (RADIX_PTE_INDEX_SIZE + 3) #define RADIX_PTE_FRAG_NR (PAGE_SIZE >> RADIX_PTE_FRAG_SIZE_SHIFT) +#define RADIX_PMD_FRAG_SIZE_SHIFT (RADIX_PMD_INDEX_SIZE + 3) +#define RADIX_PMD_FRAG_NR (PAGE_SIZE >> RADIX_PMD_FRAG_SIZE_SHIFT) + #endif /* _ASM_POWERPC_PGTABLE_RADIX_4K_H */ diff --git a/arch/powerpc/include/asm/book3s/64/radix-64k.h b/arch/powerpc/include/asm/book3s/64/radix-64k.h index 830082496876..ccb78ca9d0c5 100644 --- a/arch/powerpc/include/asm/book3s/64/radix-64k.h +++ b/arch/powerpc/include/asm/book3s/64/radix-64k.h @@ -16,4 +16,8 @@ */ #define RADIX_PTE_FRAG_SIZE_SHIFT (RADIX_PTE_INDEX_SIZE + 3) #define RADIX_PTE_FRAG_NR (PAGE_SIZE >> RADIX_PTE_FRAG_SIZE_SHIFT) + +#define RADIX_PMD_FRAG_SIZE_SHIFT (RADIX_PMD_INDEX_SIZE + 3) +#define RADIX_PMD_FRAG_NR (PAGE_SIZE >> RADIX_PMD_FRAG_SIZE_SHIFT) + #endif /* _ASM_POWERPC_PGTABLE_RADIX_64K_H */ diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index 0bd3790d35df..63b1c1882e22 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -1010,6 +1010,8 @@ void __init hash__early_init_mmu(void) */ __pte_frag_nr = H_PTE_FRAG_NR; __pte_frag_size_shift = H_PTE_FRAG_SIZE_SHIFT; + __pmd_frag_nr = H_PMD_FRAG_NR; + __pmd_frag_size_shift = H_PMD_FRAG_SIZE_SHIFT; __pte_index_size = H_PTE_INDEX_SIZE; __pmd_index_size = H_PMD_INDEX_SIZE; diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c index 87ee78973a35..f3d4b4a0e561 100644 --- a/arch/powerpc/mm/mmu_context_book3s64.c +++ b/arch/powerpc/mm/mmu_context_book3s64.c @@ -160,6 +160,7 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm) mm->context.id = index; mm->context.pte_frag = NULL; + mm->context.pmd_frag = NULL; #ifdef CONFIG_SPAPR_TCE_IOMMU mm_iommu_init(mm); #endif @@ -190,16 +191,11 @@ static void destroy_contexts(mm_context_t *ctx) spin_unlock(&mmu_context_lock); } -static void destroy_pagetable_page(struct mm_struct *mm) +static void pte_frag_destroy(void *pte_frag) { int count; - void *pte_frag; struct page *page; - pte_frag = mm->context.pte_frag; - if (!pte_frag) - return; - page = virt_to_page(pte_frag); /* drop all the pending references */ count = ((unsigned long)pte_frag & ~PAGE_MASK) >> PTE_FRAG_SIZE_SHIFT; @@ -210,6 +206,35 @@ static void destroy_pagetable_page(struct mm_struct *mm) } } +static void pmd_frag_destroy(void *pmd_frag) +{ + int count; + struct page *page; + + page = virt_to_page(pmd_frag); + /* drop all the pending references */ + count = ((unsigned long)pmd_frag & ~PAGE_MASK) >> PMD_FRAG_SIZE_SHIFT; + /* We allow PTE_FRAG_NR fragments from a PTE page */ + if (page_ref_sub_and_test(page, PMD_FRAG_NR - count)) { + pgtable_pmd_page_dtor(page); + free_unref_page(page); + } +} + +static void destroy_pagetable_page(struct mm_struct *mm) +{ + void *frag; + + frag = mm->context.pte_frag; + if (frag) + pte_frag_destroy(frag); + + frag = mm->context.pmd_frag; + if (frag) + pmd_frag_destroy(frag); + return; +} + void destroy_context(struct mm_struct *mm) { #ifdef CONFIG_SPAPR_TCE_IOMMU diff --git a/arch/powerpc/mm/pgtable-book3s64.c b/arch/powerpc/mm/pgtable-book3s64.c index 0a05e99b54a1..47323ed8d7b5 100644 --- a/arch/powerpc/mm/pgtable-book3s64.c +++ b/arch/powerpc/mm/pgtable-book3s64.c @@ -20,6 +20,11 @@ #include "mmu_decl.h" #include <trace/events/thp.h> +unsigned long __pmd_frag_nr; +EXPORT_SYMBOL(__pmd_frag_nr); +unsigned long __pmd_frag_size_shift; +EXPORT_SYMBOL(__pmd_frag_size_shift); + int (*register_process_table)(unsigned long base, unsigned long page_size, unsigned long tbl_size); @@ -226,6 +231,85 @@ void mmu_partition_table_set_entry(unsigned int lpid, unsigned long dw0, } EXPORT_SYMBOL_GPL(mmu_partition_table_set_entry); +static pmd_t *get_pmd_from_cache(struct mm_struct *mm) +{ + void *pmd_frag, *ret; + + spin_lock(&mm->page_table_lock); + ret = mm->context.pmd_frag; + if (ret) { + pmd_frag = ret + PMD_FRAG_SIZE; + /* + * If we have taken up all the fragments mark PTE page NULL + */ + if (((unsigned long)pmd_frag & ~PAGE_MASK) == 0) + pmd_frag = NULL; + mm->context.pmd_frag = pmd_frag; + } + spin_unlock(&mm->page_table_lock); + return (pmd_t *)ret; +} + +static pmd_t *__alloc_for_pmdcache(struct mm_struct *mm) +{ + void *ret = NULL; + struct page *page; + gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO; + + if (mm == &init_mm) + gfp &= ~__GFP_ACCOUNT; + page = alloc_page(gfp); + if (!page) + return NULL; + if (!pgtable_pmd_page_ctor(page)) { + __free_pages(page, 0); + return NULL; + } + + ret = page_address(page); + /* + * if we support only one fragment just return the + * allocated page. + */ + if (PMD_FRAG_NR == 1) + return ret; + + spin_lock(&mm->page_table_lock); + /* + * If we find pgtable_page set, we return + * the allocated page with single fragement + * count. + */ + if (likely(!mm->context.pmd_frag)) { + set_page_count(page, PMD_FRAG_NR); + mm->context.pmd_frag = ret + PMD_FRAG_SIZE; + } + spin_unlock(&mm->page_table_lock); + + return (pmd_t *)ret; +} + +pmd_t *pmd_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr) +{ + pmd_t *pmd; + + pmd = get_pmd_from_cache(mm); + if (pmd) + return pmd; + + return __alloc_for_pmdcache(mm); +} + +void pmd_fragment_free(unsigned long *pmd) +{ + struct page *page = virt_to_page(pmd); + + if (put_page_testzero(page)) { + pgtable_pmd_page_dtor(page); + free_unref_page(page); + } +} + static pte_t *get_pte_from_cache(struct mm_struct *mm) { void *pte_frag, *ret; diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c index 473415750cbf..32e58024e7cb 100644 --- a/arch/powerpc/mm/pgtable-radix.c +++ b/arch/powerpc/mm/pgtable-radix.c @@ -640,6 +640,8 @@ void __init radix__early_init_mmu(void) #endif __pte_frag_nr = RADIX_PTE_FRAG_NR; __pte_frag_size_shift = RADIX_PTE_FRAG_SIZE_SHIFT; + __pmd_frag_nr = RADIX_PMD_FRAG_NR; + __pmd_frag_size_shift = RADIX_PMD_FRAG_SIZE_SHIFT; if (!firmware_has_feature(FW_FEATURE_LPAR)) { radix_init_native();

[V1,09/11] powerpc/mm: Implement helpers for pagetable fragment support at PMD level

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