From 3c1cb776644ec050038b22c2b6c306277e6e5764 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Wed, 12 Dec 2012 13:50:47 -0800 Subject: [PATCH] --- yaml --- r: 343299 b: refs/heads/master c: 4a6c1297268c917e9c50701906ba2f7e06812299 h: refs/heads/master i: 343297: 72527b462b7fa87041982f45b61010be3ba1ed8d 343295: 2603108975e548b79c71223f479fed427229f189 v: v3 --- [refs] | 2 +- trunk/mm/huge_memory.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+), 1 deletion(-) diff --git a/[refs] b/[refs] index 1354dce77b11..3d49d2da54bd 100644 --- a/[refs] +++ b/[refs] @@ -1,2 +1,2 @@ --- -refs/heads/master: 3f7dfe24b84c0ad698c461fc9c4ba3544bbfcebf +refs/heads/master: 4a6c1297268c917e9c50701906ba2f7e06812299 diff --git a/trunk/mm/huge_memory.c b/trunk/mm/huge_memory.c index 5f902e20e8c0..04eb489a6805 100644 --- a/trunk/mm/huge_memory.c +++ b/trunk/mm/huge_memory.c @@ -47,6 +47,7 @@ static unsigned int khugepaged_scan_sleep_millisecs __read_mostly = 10000; /* during fragmentation poll the hugepage allocator once every minute */ static unsigned int khugepaged_alloc_sleep_millisecs __read_mostly = 60000; static struct task_struct *khugepaged_thread __read_mostly; +static unsigned long huge_zero_pfn __read_mostly; static DEFINE_MUTEX(khugepaged_mutex); static DEFINE_SPINLOCK(khugepaged_mm_lock); static DECLARE_WAIT_QUEUE_HEAD(khugepaged_wait); @@ -159,6 +160,29 @@ static int start_khugepaged(void) return err; } +static int __init init_huge_zero_page(void) +{ + struct page *hpage; + + hpage = alloc_pages((GFP_TRANSHUGE | __GFP_ZERO) & ~__GFP_MOVABLE, + HPAGE_PMD_ORDER); + if (!hpage) + return -ENOMEM; + + huge_zero_pfn = page_to_pfn(hpage); + return 0; +} + +static inline bool is_huge_zero_pfn(unsigned long pfn) +{ + return pfn == huge_zero_pfn; +} + +static inline bool is_huge_zero_pmd(pmd_t pmd) +{ + return is_huge_zero_pfn(pmd_pfn(pmd)); +} + #ifdef CONFIG_SYSFS static ssize_t double_flag_show(struct kobject *kobj, @@ -540,6 +564,10 @@ static int __init hugepage_init(void) if (err) return err; + err = init_huge_zero_page(); + if (err) + goto out; + err = khugepaged_slab_init(); if (err) goto out; @@ -562,6 +590,8 @@ static int __init hugepage_init(void) return 0; out: + if (huge_zero_pfn) + __free_page(pfn_to_page(huge_zero_pfn)); hugepage_exit_sysfs(hugepage_kobj); return err; }