diff options
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 41 |
1 files changed, 25 insertions, 16 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index b49ee126d4d1..41ef7547e822 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -89,6 +89,7 @@ static unsigned int khugepaged_full_scans; 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 unsigned long khugepaged_sleep_expire; static struct task_struct *khugepaged_thread __read_mostly; static DEFINE_MUTEX(khugepaged_mutex); static DEFINE_SPINLOCK(khugepaged_mm_lock); @@ -467,6 +468,7 @@ static ssize_t scan_sleep_millisecs_store(struct kobject *kobj, return -EINVAL; khugepaged_scan_sleep_millisecs = msecs; + khugepaged_sleep_expire = 0; wake_up_interruptible(&khugepaged_wait); return count; @@ -494,6 +496,7 @@ static ssize_t alloc_sleep_millisecs_store(struct kobject *kobj, return -EINVAL; khugepaged_alloc_sleep_millisecs = msecs; + khugepaged_sleep_expire = 0; wake_up_interruptible(&khugepaged_wait); return count; @@ -764,10 +767,7 @@ pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma) static inline pmd_t mk_huge_pmd(struct page *page, pgprot_t prot) { - pmd_t entry; - entry = mk_pmd(page, prot); - entry = pmd_mkhuge(entry); - return entry; + return pmd_mkhuge(mk_pmd(page, prot)); } static inline struct list_head *page_deferred_list(struct page *page) @@ -1698,20 +1698,17 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, return 1; } -bool move_huge_pmd(struct vm_area_struct *vma, struct vm_area_struct *new_vma, - unsigned long old_addr, +bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr, unsigned long new_addr, unsigned long old_end, pmd_t *old_pmd, pmd_t *new_pmd) { spinlock_t *old_ptl, *new_ptl; pmd_t pmd; - struct mm_struct *mm = vma->vm_mm; if ((old_addr & ~HPAGE_PMD_MASK) || (new_addr & ~HPAGE_PMD_MASK) || - old_end - old_addr < HPAGE_PMD_SIZE || - (new_vma->vm_flags & VM_NOHUGEPAGE)) + old_end - old_addr < HPAGE_PMD_SIZE) return false; /* @@ -2797,15 +2794,25 @@ static void khugepaged_do_scan(void) put_page(hpage); } +static bool khugepaged_should_wakeup(void) +{ + return kthread_should_stop() || + time_after_eq(jiffies, khugepaged_sleep_expire); +} + static void khugepaged_wait_work(void) { if (khugepaged_has_work()) { - if (!khugepaged_scan_sleep_millisecs) + const unsigned long scan_sleep_jiffies = + msecs_to_jiffies(khugepaged_scan_sleep_millisecs); + + if (!scan_sleep_jiffies) return; + khugepaged_sleep_expire = jiffies + scan_sleep_jiffies; wait_event_freezable_timeout(khugepaged_wait, - kthread_should_stop(), - msecs_to_jiffies(khugepaged_scan_sleep_millisecs)); + khugepaged_should_wakeup(), + scan_sleep_jiffies); return; } @@ -3029,8 +3036,10 @@ void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, return; /* - * Caller holds the mmap_sem write mode, so a huge pmd cannot - * materialize from under us. + * Caller holds the mmap_sem write mode or the anon_vma lock, + * so a huge pmd cannot materialize from under us (khugepaged + * holds both the mmap_sem write mode and the anon_vma lock + * write mode). */ __split_huge_pmd(vma, pmd, address, freeze); } @@ -3113,7 +3122,7 @@ static void __split_huge_page_tail(struct page *head, int tail, VM_BUG_ON_PAGE(page_ref_count(page_tail) != 0, page_tail); /* - * tail_page->_count is zero and not changing from under us. But + * tail_page->_refcount is zero and not changing from under us. But * get_page_unless_zero() may be running from under us on the * tail_page. If we used atomic_set() below instead of atomic_inc(), we * would then run atomic_set() concurrently with @@ -3340,7 +3349,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) if (mlocked) lru_add_drain(); - /* Prevent deferred_split_scan() touching ->_count */ + /* Prevent deferred_split_scan() touching ->_refcount */ spin_lock_irqsave(&pgdata->split_queue_lock, flags); count = page_count(head); mapcount = total_mapcount(head); |