From d1837cba5d5d5458c09f0a2849db2d3c203cb8e9 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Mon, 26 Oct 2009 19:24:31 +0000 Subject: [PATCH] powerpc/mm: Cleanup initialization of hugepages on powerpc This patch simplifies the logic used to initialize hugepages on powerpc. The somewhat oddly named set_huge_psize() is renamed to add_huge_page_size() and now does all necessary verification of whether it's given a valid hugepage sizes (instead of just some) and instantiates the generic hstate structure (but no more). hugetlbpage_init() now steps through the available pagesizes, checks if they're valid for hugepages by calling add_huge_page_size() and initializes the kmem_caches for the hugepage pagetables. This means we can now eliminate the mmu_huge_psizes array, since we no longer need to pass the sizing information for the pagetable caches from set_huge_psize() into hugetlbpage_init() Determination of the default huge page size is also moved from the hash code into the general hugepage code. Signed-off-by: David Gibson Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/page_64.h | 2 +- arch/powerpc/mm/hash_utils_64.c | 10 --- arch/powerpc/mm/hugetlbpage.c | 128 ++++++++++++++++++------------------- 3 files changed, 63 insertions(+), 77 deletions(-) diff --git a/arch/powerpc/include/asm/page_64.h b/arch/powerpc/include/asm/page_64.h index 3f17b83..bfc4e02 100644 --- a/arch/powerpc/include/asm/page_64.h +++ b/arch/powerpc/include/asm/page_64.h @@ -90,7 +90,7 @@ extern unsigned int HPAGE_SHIFT; #define HPAGE_SIZE ((1UL) << HPAGE_SHIFT) #define HPAGE_MASK (~(HPAGE_SIZE - 1)) #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT) -#define HUGE_MAX_HSTATE 3 +#define HUGE_MAX_HSTATE (MMU_PAGE_COUNT-1) #endif /* __ASSEMBLY__ */ diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index 485dcd1..ef1f047 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -481,16 +481,6 @@ static void __init htab_init_page_sizes(void) #ifdef CONFIG_HUGETLB_PAGE /* Reserve 16G huge page memory sections for huge pages */ of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL); - -/* Set default large page size. Currently, we pick 16M or 1M depending - * on what is available - */ - if (mmu_psize_defs[MMU_PAGE_16M].shift) - HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift; - /* With 4k/4level pagetables, we can't (for now) cope with a - * huge page size < PMD_SIZE */ - else if (mmu_psize_defs[MMU_PAGE_1M].shift) - HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift; #endif /* CONFIG_HUGETLB_PAGE */ } diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index 95220a5..a7161c0 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -37,27 +37,17 @@ static unsigned long gpage_freearray[MAX_NUMBER_GPAGES]; static unsigned nr_gpages; -/* Array of valid huge page sizes - non-zero value(hugepte_shift) is - * stored for the huge page sizes that are valid. - */ -static unsigned int mmu_huge_psizes[MMU_PAGE_COUNT] = { }; /* initialize all to 0 */ - /* Flag to mark huge PD pointers. This means pmd_bad() and pud_bad() * will choke on pointers to hugepte tables, which is handy for * catching screwups early. */ static inline int shift_to_mmu_psize(unsigned int shift) { - switch (shift) { -#ifndef CONFIG_PPC_64K_PAGES - case PAGE_SHIFT_64K: - return MMU_PAGE_64K; -#endif - case PAGE_SHIFT_16M: - return MMU_PAGE_16M; - case PAGE_SHIFT_16G: - return MMU_PAGE_16G; - } + int psize; + + for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) + if (mmu_psize_defs[psize].shift == shift) + return psize; return -1; } @@ -502,8 +492,6 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, struct hstate *hstate = hstate_file(file); int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate)); - if (!mmu_huge_psizes[mmu_psize]) - return -EINVAL; return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0); } @@ -666,47 +654,46 @@ repeat: return err; } -static void __init set_huge_psize(int psize) +static int __init add_huge_page_size(unsigned long long size) { - unsigned pdshift; + int shift = __ffs(size); + int mmu_psize; /* Check that it is a page size supported by the hardware and - * that it fits within pagetable limits. */ - if (mmu_psize_defs[psize].shift && - mmu_psize_defs[psize].shift < SID_SHIFT_1T && - (mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT || - mmu_psize_defs[psize].shift == PAGE_SHIFT_64K || - mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) { - /* Return if huge page size has already been setup or is the - * same as the base page size. */ - if (mmu_huge_psizes[psize] || - mmu_psize_defs[psize].shift == PAGE_SHIFT) - return; - hugetlb_add_hstate(mmu_psize_defs[psize].shift - PAGE_SHIFT); + * that it fits within pagetable and slice limits. */ + if (!is_power_of_2(size) + || (shift > SLICE_HIGH_SHIFT) || (shift <= PAGE_SHIFT)) + return -EINVAL; - if (mmu_psize_defs[psize].shift < PMD_SHIFT) - pdshift = PMD_SHIFT; - else if (mmu_psize_defs[psize].shift < PUD_SHIFT) - pdshift = PUD_SHIFT; - else - pdshift = PGDIR_SHIFT; - mmu_huge_psizes[psize] = pdshift - mmu_psize_defs[psize].shift; - } + if ((mmu_psize = shift_to_mmu_psize(shift)) < 0) + return -EINVAL; + +#ifdef CONFIG_SPU_FS_64K_LS + /* Disable support for 64K huge pages when 64K SPU local store + * support is enabled as the current implementation conflicts. + */ + if (shift == PAGE_SHIFT_64K) + return -EINVAL; +#endif /* CONFIG_SPU_FS_64K_LS */ + + BUG_ON(mmu_psize_defs[mmu_psize].shift != shift); + + /* Return if huge page size has already been setup */ + if (size_to_hstate(size)) + return 0; + + hugetlb_add_hstate(shift - PAGE_SHIFT); + + return 0; } static int __init hugepage_setup_sz(char *str) { unsigned long long size; - int mmu_psize; - int shift; size = memparse(str, &str); - shift = __ffs(size); - mmu_psize = shift_to_mmu_psize(shift); - if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) - set_huge_psize(mmu_psize); - else + if (add_huge_page_size(size) != 0) printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size); return 1; @@ -720,30 +707,39 @@ static int __init hugetlbpage_init(void) if (!cpu_has_feature(CPU_FTR_16M_PAGE)) return -ENODEV; - /* Add supported huge page sizes. Need to change - * HUGE_MAX_HSTATE if the number of supported huge page sizes - * changes. - */ - set_huge_psize(MMU_PAGE_16M); - set_huge_psize(MMU_PAGE_16G); + for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { + unsigned shift; + unsigned pdshift; - /* Temporarily disable support for 64K huge pages when 64K SPU local - * store support is enabled as the current implementation conflicts. - */ -#ifndef CONFIG_SPU_FS_64K_LS - set_huge_psize(MMU_PAGE_64K); -#endif + if (!mmu_psize_defs[psize].shift) + continue; - for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { - if (mmu_huge_psizes[psize]) { - pgtable_cache_add(mmu_huge_psizes[psize], NULL); - if (!PGT_CACHE(mmu_huge_psizes[psize])) - panic("hugetlbpage_init(): could not create " - "pgtable cache for %d bit pagesize\n", - mmu_psize_to_shift(psize)); - } + shift = mmu_psize_to_shift(psize); + + if (add_huge_page_size(1ULL << shift) < 0) + continue; + + if (shift < PMD_SHIFT) + pdshift = PMD_SHIFT; + else if (shift < PUD_SHIFT) + pdshift = PUD_SHIFT; + else + pdshift = PGDIR_SHIFT; + + pgtable_cache_add(pdshift - shift, NULL); + if (!PGT_CACHE(pdshift - shift)) + panic("hugetlbpage_init(): could not create " + "pgtable cache for %d bit pagesize\n", shift); } + /* Set default large page size. Currently, we pick 16M or 1M + * depending on what is available + */ + if (mmu_psize_defs[MMU_PAGE_16M].shift) + HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift; + else if (mmu_psize_defs[MMU_PAGE_1M].shift) + HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift; + return 0; } -- 2.7.4