.attrs = khugepaged_attr,
.name = "khugepaged",
};
-#endif /* CONFIG_SYSFS */
-static int __init hugepage_init(void)
+static int __init hugepage_init_sysfs(struct kobject **hugepage_kobj)
{
int err;
-#ifdef CONFIG_SYSFS
- static struct kobject *hugepage_kobj;
-#endif
- err = -EINVAL;
- if (!has_transparent_hugepage()) {
- transparent_hugepage_flags = 0;
- goto out;
- }
-
-#ifdef CONFIG_SYSFS
- err = -ENOMEM;
- hugepage_kobj = kobject_create_and_add("transparent_hugepage", mm_kobj);
- if (unlikely(!hugepage_kobj)) {
+ *hugepage_kobj = kobject_create_and_add("transparent_hugepage", mm_kobj);
+ if (unlikely(!*hugepage_kobj)) {
printk(KERN_ERR "hugepage: failed kobject create\n");
- goto out;
+ return -ENOMEM;
}
- err = sysfs_create_group(hugepage_kobj, &hugepage_attr_group);
+ err = sysfs_create_group(*hugepage_kobj, &hugepage_attr_group);
if (err) {
printk(KERN_ERR "hugepage: failed register hugeage group\n");
- goto out;
+ goto delete_obj;
}
- err = sysfs_create_group(hugepage_kobj, &khugepaged_attr_group);
+ err = sysfs_create_group(*hugepage_kobj, &khugepaged_attr_group);
if (err) {
printk(KERN_ERR "hugepage: failed register hugeage group\n");
- goto out;
+ goto remove_hp_group;
}
-#endif
+
+ return 0;
+
+remove_hp_group:
+ sysfs_remove_group(*hugepage_kobj, &hugepage_attr_group);
+delete_obj:
+ kobject_put(*hugepage_kobj);
+ return err;
+}
+
+static void __init hugepage_exit_sysfs(struct kobject *hugepage_kobj)
+{
+ sysfs_remove_group(hugepage_kobj, &khugepaged_attr_group);
+ sysfs_remove_group(hugepage_kobj, &hugepage_attr_group);
+ kobject_put(hugepage_kobj);
+}
+#else
+static inline int hugepage_init_sysfs(struct kobject **hugepage_kobj)
+{
+ return 0;
+}
+
+static inline void hugepage_exit_sysfs(struct kobject *hugepage_kobj)
+{
+}
+#endif /* CONFIG_SYSFS */
+
+static int __init hugepage_init(void)
+{
+ int err;
+ struct kobject *hugepage_kobj;
+
+ if (!has_transparent_hugepage()) {
+ transparent_hugepage_flags = 0;
+ return -EINVAL;
+ }
+
+ err = hugepage_init_sysfs(&hugepage_kobj);
+ if (err)
+ return err;
err = khugepaged_slab_init();
if (err)
set_recommended_min_free_kbytes();
+ return 0;
out:
+ hugepage_exit_sysfs(hugepage_kobj);
return err;
}
module_init(hugepage_init)
set_pmd_at(mm, haddr, pmd, entry);
prepare_pmd_huge_pte(pgtable, mm);
add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
+ mm->nr_ptes++;
spin_unlock(&mm->page_table_lock);
}
pmd = pmd_mkold(pmd_wrprotect(pmd));
set_pmd_at(dst_mm, addr, dst_pmd, pmd);
prepare_pmd_huge_pte(pgtable, dst_mm);
+ dst_mm->nr_ptes++;
ret = 0;
out_unlock:
for (i = 0; i < HPAGE_PMD_NR; i++) {
copy_user_highpage(pages[i], page + i,
- haddr + PAGE_SHIFT*i, vma);
+ haddr + PAGE_SIZE * i, vma);
__SetPageUptodate(pages[i]);
cond_resched();
}
}
kfree(pages);
- mm->nr_ptes++;
smp_wmb(); /* make pte visible before pmd */
pmd_populate(mm, pmd, pgtable);
page_remove_rmap(page);
page += (addr & ~HPAGE_PMD_MASK) >> PAGE_SHIFT;
VM_BUG_ON(!PageCompound(page));
if (flags & FOLL_GET)
- get_page(page);
+ get_page_foll(page);
out:
return page;
}
int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
- pmd_t *pmd)
+ pmd_t *pmd, unsigned long addr)
{
int ret = 0;
- spin_lock(&tlb->mm->page_table_lock);
- if (likely(pmd_trans_huge(*pmd))) {
- if (unlikely(pmd_trans_splitting(*pmd))) {
- spin_unlock(&tlb->mm->page_table_lock);
- wait_split_huge_page(vma->anon_vma,
- pmd);
- } else {
- struct page *page;
- pgtable_t pgtable;
- pgtable = get_pmd_huge_pte(tlb->mm);
- page = pmd_page(*pmd);
- pmd_clear(pmd);
- page_remove_rmap(page);
- VM_BUG_ON(page_mapcount(page) < 0);
- add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
- VM_BUG_ON(!PageHead(page));
- spin_unlock(&tlb->mm->page_table_lock);
- tlb_remove_page(tlb, page);
- pte_free(tlb->mm, pgtable);
- ret = 1;
- }
- } else
+ if (__pmd_trans_huge_lock(pmd, vma) == 1) {
+ struct page *page;
+ pgtable_t pgtable;
+ pgtable = get_pmd_huge_pte(tlb->mm);
+ page = pmd_page(*pmd);
+ pmd_clear(pmd);
+ tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
+ page_remove_rmap(page);
+ VM_BUG_ON(page_mapcount(page) < 0);
+ add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
+ VM_BUG_ON(!PageHead(page));
+ tlb->mm->nr_ptes--;
spin_unlock(&tlb->mm->page_table_lock);
-
+ tlb_remove_page(tlb, page);
+ pte_free(tlb->mm, pgtable);
+ ret = 1;
+ }
return ret;
}
{
int ret = 0;
- spin_lock(&vma->vm_mm->page_table_lock);
- if (likely(pmd_trans_huge(*pmd))) {
- ret = !pmd_trans_splitting(*pmd);
- spin_unlock(&vma->vm_mm->page_table_lock);
- if (unlikely(!ret))
- wait_split_huge_page(vma->anon_vma, pmd);
- else {
- /*
- * All logical pages in the range are present
- * if backed by a huge page.
- */
- memset(vec, 1, (end - addr) >> PAGE_SHIFT);
- }
- } else
+ if (__pmd_trans_huge_lock(pmd, vma) == 1) {
+ /*
+ * All logical pages in the range are present
+ * if backed by a huge page.
+ */
spin_unlock(&vma->vm_mm->page_table_lock);
+ memset(vec, 1, (end - addr) >> PAGE_SHIFT);
+ ret = 1;
+ }
return ret;
}
goto out;
}
- spin_lock(&mm->page_table_lock);
- if (likely(pmd_trans_huge(*old_pmd))) {
- if (pmd_trans_splitting(*old_pmd)) {
- spin_unlock(&mm->page_table_lock);
- wait_split_huge_page(vma->anon_vma, old_pmd);
- ret = -1;
- } else {
- pmd = pmdp_get_and_clear(mm, old_addr, old_pmd);
- VM_BUG_ON(!pmd_none(*new_pmd));
- set_pmd_at(mm, new_addr, new_pmd, pmd);
- spin_unlock(&mm->page_table_lock);
- ret = 1;
- }
- } else {
+ ret = __pmd_trans_huge_lock(old_pmd, vma);
+ if (ret == 1) {
+ pmd = pmdp_get_and_clear(mm, old_addr, old_pmd);
+ VM_BUG_ON(!pmd_none(*new_pmd));
+ set_pmd_at(mm, new_addr, new_pmd, pmd);
spin_unlock(&mm->page_table_lock);
}
out:
struct mm_struct *mm = vma->vm_mm;
int ret = 0;
- spin_lock(&mm->page_table_lock);
+ if (__pmd_trans_huge_lock(pmd, vma) == 1) {
+ pmd_t entry;
+ entry = pmdp_get_and_clear(mm, addr, pmd);
+ entry = pmd_modify(entry, newprot);
+ set_pmd_at(mm, addr, pmd, entry);
+ spin_unlock(&vma->vm_mm->page_table_lock);
+ ret = 1;
+ }
+
+ return ret;
+}
+
+/*
+ * Returns 1 if a given pmd maps a stable (not under splitting) thp.
+ * Returns -1 if it maps a thp under splitting. Returns 0 otherwise.
+ *
+ * Note that if it returns 1, this routine returns without unlocking page
+ * table locks. So callers must unlock them.
+ */
+int __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma)
+{
+ spin_lock(&vma->vm_mm->page_table_lock);
if (likely(pmd_trans_huge(*pmd))) {
if (unlikely(pmd_trans_splitting(*pmd))) {
- spin_unlock(&mm->page_table_lock);
+ spin_unlock(&vma->vm_mm->page_table_lock);
wait_split_huge_page(vma->anon_vma, pmd);
+ return -1;
} else {
- pmd_t entry;
-
- entry = pmdp_get_and_clear(mm, addr, pmd);
- entry = pmd_modify(entry, newprot);
- set_pmd_at(mm, addr, pmd, entry);
- spin_unlock(&vma->vm_mm->page_table_lock);
- flush_tlb_range(vma, addr, addr + HPAGE_PMD_SIZE);
- ret = 1;
+ /* Thp mapped by 'pmd' is stable, so we can
+ * handle it as it is. */
+ return 1;
}
- } else
- spin_unlock(&vma->vm_mm->page_table_lock);
-
- return ret;
+ }
+ spin_unlock(&vma->vm_mm->page_table_lock);
+ return 0;
}
pmd_t *page_check_address_pmd(struct page *page,
static void __split_huge_page_refcount(struct page *page)
{
int i;
- unsigned long head_index = page->index;
struct zone *zone = page_zone(page);
- int zonestat;
+ int tail_count = 0;
/* prevent PageLRU to go away from under us, and freeze lru stats */
spin_lock_irq(&zone->lru_lock);
compound_lock(page);
+ /* complete memcg works before add pages to LRU */
+ mem_cgroup_split_huge_fixup(page);
- for (i = 1; i < HPAGE_PMD_NR; i++) {
+ for (i = HPAGE_PMD_NR - 1; i >= 1; i--) {
struct page *page_tail = page + i;
- /* tail_page->_count cannot change */
- atomic_sub(atomic_read(&page_tail->_count), &page->_count);
- BUG_ON(page_count(page) <= 0);
- atomic_add(page_mapcount(page) + 1, &page_tail->_count);
- BUG_ON(atomic_read(&page_tail->_count) <= 0);
+ /* tail_page->_mapcount cannot change */
+ BUG_ON(page_mapcount(page_tail) < 0);
+ tail_count += page_mapcount(page_tail);
+ /* check for overflow */
+ BUG_ON(tail_count < 0);
+ BUG_ON(atomic_read(&page_tail->_count) != 0);
+ /*
+ * tail_page->_count 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_add(), we
+ * would then run atomic_set() concurrently with
+ * get_page_unless_zero(), and atomic_set() is
+ * implemented in C not using locked ops. spin_unlock
+ * on x86 sometime uses locked ops because of PPro
+ * errata 66, 92, so unless somebody can guarantee
+ * atomic_set() here would be safe on all archs (and
+ * not only on x86), it's safer to use atomic_add().
+ */
+ atomic_add(page_mapcount(page) + page_mapcount(page_tail) + 1,
+ &page_tail->_count);
/* after clearing PageTail the gup refcount can be released */
smp_mb();
(1L << PG_uptodate)));
page_tail->flags |= (1L << PG_dirty);
- /*
- * 1) clear PageTail before overwriting first_page
- * 2) clear PageTail before clearing PageHead for VM_BUG_ON
- */
+ /* clear PageTail before overwriting first_page */
smp_wmb();
/*
* status is achieved setting a reserved bit in the
* pmd, not by clearing the present bit.
*/
- BUG_ON(page_mapcount(page_tail));
page_tail->_mapcount = page->_mapcount;
BUG_ON(page_tail->mapping);
page_tail->mapping = page->mapping;
- page_tail->index = ++head_index;
+ page_tail->index = page->index + i;
BUG_ON(!PageAnon(page_tail));
BUG_ON(!PageUptodate(page_tail));
BUG_ON(!PageDirty(page_tail));
BUG_ON(!PageSwapBacked(page_tail));
- mem_cgroup_split_huge_fixup(page, page_tail);
lru_add_page_tail(zone, page, page_tail);
}
+ atomic_sub(tail_count, &page->_count);
+ BUG_ON(atomic_read(&page->_count) <= 0);
__dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES);
__mod_zone_page_state(zone, NR_ANON_PAGES, HPAGE_PMD_NR);
- /*
- * A hugepage counts for HPAGE_PMD_NR pages on the LRU statistics,
- * so adjust those appropriately if this page is on the LRU.
- */
- if (PageLRU(page)) {
- zonestat = NR_LRU_BASE + page_lru(page);
- __mod_zone_page_state(zone, zonestat, -(HPAGE_PMD_NR-1));
- }
-
ClearPageCompound(page);
compound_unlock(page);
spin_unlock_irq(&zone->lru_lock);
pte_unmap(pte);
}
- mm->nr_ptes++;
smp_wmb(); /* make pte visible before pmd */
/*
* Up to this point the pmd is present and huge and
BUG_ON(!pmd_none(*pmd));
page_add_new_anon_rmap(new_page, vma, address);
set_pmd_at(mm, address, pmd, _pmd);
- update_mmu_cache(vma, address, entry);
+ update_mmu_cache(vma, address, _pmd);
prepare_pmd_huge_pte(pgtable, mm);
- mm->nr_ptes--;
spin_unlock(&mm->page_table_lock);
#ifndef CONFIG_NUMA
{
struct mm_struct *mm = mm_slot->mm;
- VM_BUG_ON(!spin_is_locked(&khugepaged_mm_lock));
+ VM_BUG_ON(NR_CPUS != 1 && !spin_is_locked(&khugepaged_mm_lock));
if (khugepaged_test_exit(mm)) {
/* free mm_slot */
int progress = 0;
VM_BUG_ON(!pages);
- VM_BUG_ON(!spin_is_locked(&khugepaged_mm_lock));
+ VM_BUG_ON(NR_CPUS != 1 && !spin_is_locked(&khugepaged_mm_lock));
if (khugepaged_scan.mm_slot)
mm_slot = khugepaged_scan.mm_slot;
static void khugepaged_alloc_sleep(void)
{
- DEFINE_WAIT(wait);
- add_wait_queue(&khugepaged_wait, &wait);
- schedule_timeout_interruptible(
- msecs_to_jiffies(
- khugepaged_alloc_sleep_millisecs));
- remove_wait_queue(&khugepaged_wait, &wait);
+ wait_event_freezable_timeout(khugepaged_wait, false,
+ msecs_to_jiffies(khugepaged_alloc_sleep_millisecs));
}
#ifndef CONFIG_NUMA
if (unlikely(kthread_should_stop()))
break;
if (khugepaged_has_work()) {
- DEFINE_WAIT(wait);
if (!khugepaged_scan_sleep_millisecs)
continue;
- add_wait_queue(&khugepaged_wait, &wait);
- schedule_timeout_interruptible(
- msecs_to_jiffies(
- khugepaged_scan_sleep_millisecs));
- remove_wait_queue(&khugepaged_wait, &wait);
+ wait_event_freezable_timeout(khugepaged_wait, false,
+ msecs_to_jiffies(khugepaged_scan_sleep_millisecs));
} else if (khugepaged_enabled())
wait_event_freezable(khugepaged_wait,
khugepaged_wait_event());
projects / linux-flexiantxendom0-3.2.10.git / blobdiff