Subject: + mm-add-debugfs-tunable-for-fault_around_order.patch added to -mm tree To: kirill.shutemov@xxxxxxxxxxxxxxx,ak@xxxxxxxxxxxxxxx,dave.hansen@xxxxxxxxxxxxxxx,david@xxxxxxxxxxxxx,matthew.r.wilcox@xxxxxxxxx,mgorman@xxxxxxx,quning@xxxxxxxxx,riel@xxxxxxxxxx,torvalds@xxxxxxxxxxxxxxxxxxxx,viro@xxxxxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Fri, 28 Feb 2014 16:01:40 -0800 The patch titled Subject: mm: add debugfs tunable for fault_around_order has been added to the -mm tree. Its filename is mm-add-debugfs-tunable-for-fault_around_order.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-add-debugfs-tunable-for-fault_around_order.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-add-debugfs-tunable-for-fault_around_order.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Subject: mm: add debugfs tunable for fault_around_order Let's allow people to tweak faultaround at runtime. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Matthew Wilcox <matthew.r.wilcox@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Dave Chinner <david@xxxxxxxxxxxxx> Cc: Ning Qu <quning@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory.c | 68 ++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 61 insertions(+), 7 deletions(-) diff -puN mm/memory.c~mm-add-debugfs-tunable-for-fault_around_order mm/memory.c --- a/mm/memory.c~mm-add-debugfs-tunable-for-fault_around_order +++ a/mm/memory.c @@ -60,6 +60,7 @@ #include <linux/migrate.h> #include <linux/string.h> #include <linux/dma-debug.h> +#include <linux/debugfs.h> #include <asm/io.h> #include <asm/pgalloc.h> @@ -3344,8 +3345,63 @@ void do_set_pte(struct vm_area_struct *v } #define FAULT_AROUND_ORDER 4 -#define FAULT_AROUND_PAGES (1UL << FAULT_AROUND_ORDER) -#define FAULT_AROUND_MASK ~((1UL << (PAGE_SHIFT + FAULT_AROUND_ORDER)) - 1) + +#ifdef CONFIG_DEBUG_FS +static unsigned int fault_around_order = FAULT_AROUND_ORDER; + +static int fault_around_order_get(void *data, u64 *val) +{ + *val = fault_around_order; + return 0; +} + +static int fault_around_order_set(void *data, u64 val) +{ + BUILD_BUG_ON((1UL << FAULT_AROUND_ORDER) > PTRS_PER_PTE); + if (1UL << val > PTRS_PER_PTE) + return -EINVAL; + fault_around_order = val; + return 0; +} +DEFINE_SIMPLE_ATTRIBUTE(fault_around_order_fops, + fault_around_order_get, fault_around_order_set, "%llu\n"); + +static int __init fault_around_debugfs(void) +{ + void *ret; + + ret = debugfs_create_file("fault_around_order", 0644, NULL, NULL, + &fault_around_order_fops); + if (!ret) + pr_warning("Failed to create fault_around_order in debugfs"); + return 0; +} +late_initcall(fault_around_debugfs); + +static inline unsigned long fault_around_pages(void) +{ + return 1UL << fault_around_order; +} + +static inline unsigned long fault_around_mask(void) +{ + return ~((1UL << (PAGE_SHIFT + fault_around_order)) - 1); +} +#else +static inline unsigned long fault_around_pages(void) +{ + unsigned long nr_pages; + + nr_pages = 1UL << FAULT_AROUND_ORDER; + BUILD_BUG_ON(nr_pages > PTRS_PER_PTE); + return nr_pages; +} + +static inline unsigned long fault_around_mask(void) +{ + return ~((1UL << (PAGE_SHIFT + FAULT_AROUND_ORDER)) - 1); +} +#endif static void do_fault_around(struct vm_area_struct *vma, unsigned long address, pte_t *pte, pgoff_t pgoff, unsigned int flags) @@ -3355,21 +3411,19 @@ static void do_fault_around(struct vm_ar struct vm_fault vmf; int off; - BUILD_BUG_ON(FAULT_AROUND_PAGES > PTRS_PER_PTE); - - start_addr = max(address & FAULT_AROUND_MASK, vma->vm_start); + start_addr = max(address & fault_around_mask(), vma->vm_start); off = ((address - start_addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1); pte -= off; pgoff -= off; /* * max_pgoff is either end of page table or end of vma - * or FAULT_AROUND_PAGES from pgoff, depending what is neast. + * or fault_around_pages() from pgoff, depending what is neast. */ max_pgoff = pgoff - ((start_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) + PTRS_PER_PTE - 1; max_pgoff = min3(max_pgoff, vma_pages(vma) + vma->vm_pgoff - 1, - pgoff + FAULT_AROUND_PAGES - 1); + pgoff + fault_around_pages() - 1); /* Check if it makes any sense to call ->map_pages */ while (!pte_none(*pte)) { _ Patches currently in -mm which might be from kirill.shutemov@xxxxxxxxxxxxxxx are origin.patch mm-close-pagetail-race.patch mm-page_alloc-make-first_page-visible-before-pagetail.patch mm-include-vm_mixedmap-flag-in-the-vm_special-list-to-avoid-munlocking.patch pagewalk-update-page-table-walker-core.patch pagewalk-add-walk_page_vma.patch smaps-redefine-callback-functions-for-page-table-walker.patch clear_refs-redefine-callback-functions-for-page-table-walker.patch pagemap-redefine-callback-functions-for-page-table-walker.patch numa_maps-redefine-callback-functions-for-page-table-walker.patch memcg-redefine-callback-functions-for-page-table-walker.patch madvise-redefine-callback-functions-for-page-table-walker.patch arch-powerpc-mm-subpage-protc-use-walk_page_vma-instead-of-walk_page_range.patch pagewalk-remove-argument-hmask-from-hugetlb_entry.patch mempolicy-apply-page-table-walker-on-queue_pages_range.patch mm-rename-__do_fault-do_fault.patch mm-do_fault-extract-to-call-vm_ops-do_fault-to-separate-function.patch mm-introduce-do_read_fault.patch mm-introduce-do_cow_fault.patch mm-introduce-do_shared_fault-and-drop-do_fault.patch mm-introduce-do_shared_fault-and-drop-do_fault-fix.patch mm-introduce-do_shared_fault-and-drop-do_fault-fix-fix.patch mm-consolidate-code-to-call-vm_ops-page_mkwrite.patch mm-consolidate-code-to-call-vm_ops-page_mkwrite-fix.patch mm-consolidate-code-to-setup-pte.patch mm-thp-drop-do_huge_pmd_wp_zero_page_fallback.patch mm-revert-thp-make-madv_hugepage-check-for-mm-def_flags.patch mm-revert-thp-make-madv_hugepage-check-for-mm-def_flags-ignore-madv_hugepage-on-s390-to-prevent-sigsegv-in-qemu.patch mm-thp-add-vm_init_def_mask-and-prctl_thp_disable.patch exec-kill-the-unnecessary-mm-def_flags-setting-in-load_elf_binary.patch mm-disable-split-page-table-lock-for-mmu.patch mm-introduce-vm_ops-map_pages.patch mm-implement-map_pages-for-page-cache.patch mm-cleanup-size-checks-in-filemap_fault-and-filemap_map_pages.patch mm-add-debugfs-tunable-for-fault_around_order.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html