#include <linux/hashtable.h>
#include <linux/userfaultfd_k.h>
#include <linux/page_idle.h>
+#include <linux/shmem_fs.h>
#include <asm/tlb.h>
#include <asm/pgalloc.h>
SCAN_SWAP_CACHE_PAGE,
SCAN_DEL_PAGE_LRU,
SCAN_ALLOC_HUGE_PAGE_FAIL,
- SCAN_CGROUP_CHARGE_FAIL
+ SCAN_CGROUP_CHARGE_FAIL,
+ SCAN_EXCEED_SWAP_PTE
};
#define CREATE_TRACE_POINTS
* fault.
*/
static unsigned int khugepaged_max_ptes_none __read_mostly;
+static unsigned int khugepaged_max_ptes_swap __read_mostly;
static int khugepaged(void *none);
static int khugepaged_slab_init(void);
&enabled_attr.attr,
&defrag_attr.attr,
&use_zero_page_attr.attr,
+#ifdef CONFIG_SHMEM
+ &shmem_enabled_attr.attr,
+#endif
#ifdef CONFIG_DEBUG_VM
&debug_cow_attr.attr,
#endif
__ATTR(max_ptes_none, 0644, khugepaged_max_ptes_none_show,
khugepaged_max_ptes_none_store);
+static ssize_t khugepaged_max_ptes_swap_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", khugepaged_max_ptes_swap);
+}
+
+static ssize_t khugepaged_max_ptes_swap_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ int err;
+ unsigned long max_ptes_swap;
+
+ err = kstrtoul(buf, 10, &max_ptes_swap);
+ if (err || max_ptes_swap > HPAGE_PMD_NR-1)
+ return -EINVAL;
+
+ khugepaged_max_ptes_swap = max_ptes_swap;
+
+ return count;
+}
+
+static struct kobj_attribute khugepaged_max_ptes_swap_attr =
+ __ATTR(max_ptes_swap, 0644, khugepaged_max_ptes_swap_show,
+ khugepaged_max_ptes_swap_store);
+
static struct attribute *khugepaged_attr[] = {
&khugepaged_defrag_attr.attr,
&khugepaged_max_ptes_none_attr.attr,
&full_scans_attr.attr,
&scan_sleep_millisecs_attr.attr,
&alloc_sleep_millisecs_attr.attr,
+ &khugepaged_max_ptes_swap_attr.attr,
NULL,
};
khugepaged_pages_to_scan = HPAGE_PMD_NR * 8;
khugepaged_max_ptes_none = HPAGE_PMD_NR - 1;
+ khugepaged_max_ptes_swap = HPAGE_PMD_NR / 8;
/*
* hugepages can't be allocated by the buddy allocator
*/
return pmd;
}
-static inline pmd_t mk_huge_pmd(struct page *page, pgprot_t prot)
-{
- return pmd_mkhuge(mk_pmd(page, prot));
-}
-
static inline struct list_head *page_deferred_list(struct page *page)
{
/*
set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);
}
-static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
- struct vm_area_struct *vma,
- unsigned long address, pmd_t *pmd,
- struct page *page, gfp_t gfp,
- unsigned int flags)
+static int __do_huge_pmd_anonymous_page(struct fault_env *fe, struct page *page,
+ gfp_t gfp)
{
+ struct vm_area_struct *vma = fe->vma;
struct mem_cgroup *memcg;
pgtable_t pgtable;
- spinlock_t *ptl;
- unsigned long haddr = address & HPAGE_PMD_MASK;
+ unsigned long haddr = fe->address & HPAGE_PMD_MASK;
VM_BUG_ON_PAGE(!PageCompound(page), page);
- if (mem_cgroup_try_charge(page, mm, gfp, &memcg, true)) {
+ if (mem_cgroup_try_charge(page, vma->vm_mm, gfp, &memcg, true)) {
put_page(page);
count_vm_event(THP_FAULT_FALLBACK);
return VM_FAULT_FALLBACK;
}
- pgtable = pte_alloc_one(mm, haddr);
+ pgtable = pte_alloc_one(vma->vm_mm, haddr);
if (unlikely(!pgtable)) {
mem_cgroup_cancel_charge(page, memcg, true);
put_page(page);
*/
__SetPageUptodate(page);
- ptl = pmd_lock(mm, pmd);
- if (unlikely(!pmd_none(*pmd))) {
- spin_unlock(ptl);
+ fe->ptl = pmd_lock(vma->vm_mm, fe->pmd);
+ if (unlikely(!pmd_none(*fe->pmd))) {
+ spin_unlock(fe->ptl);
mem_cgroup_cancel_charge(page, memcg, true);
put_page(page);
- pte_free(mm, pgtable);
+ pte_free(vma->vm_mm, pgtable);
} else {
pmd_t entry;
if (userfaultfd_missing(vma)) {
int ret;
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
mem_cgroup_cancel_charge(page, memcg, true);
put_page(page);
- pte_free(mm, pgtable);
- ret = handle_userfault(vma, address, flags,
- VM_UFFD_MISSING);
+ pte_free(vma->vm_mm, pgtable);
+ ret = handle_userfault(fe, VM_UFFD_MISSING);
VM_BUG_ON(ret & VM_FAULT_FALLBACK);
return ret;
}
page_add_new_anon_rmap(page, vma, haddr, true);
mem_cgroup_commit_charge(page, memcg, false, true);
lru_cache_add_active_or_unevictable(page, vma);
- pgtable_trans_huge_deposit(mm, pmd, pgtable);
- set_pmd_at(mm, haddr, pmd, entry);
- add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
- atomic_long_inc(&mm->nr_ptes);
- spin_unlock(ptl);
+ pgtable_trans_huge_deposit(vma->vm_mm, fe->pmd, pgtable);
+ set_pmd_at(vma->vm_mm, haddr, fe->pmd, entry);
+ add_mm_counter(vma->vm_mm, MM_ANONPAGES, HPAGE_PMD_NR);
+ atomic_long_inc(&vma->vm_mm->nr_ptes);
+ spin_unlock(fe->ptl);
count_vm_event(THP_FAULT_ALLOC);
}
return true;
}
-int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
- unsigned long address, pmd_t *pmd,
- unsigned int flags)
+int do_huge_pmd_anonymous_page(struct fault_env *fe)
{
+ struct vm_area_struct *vma = fe->vma;
gfp_t gfp;
struct page *page;
- unsigned long haddr = address & HPAGE_PMD_MASK;
+ unsigned long haddr = fe->address & HPAGE_PMD_MASK;
if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
return VM_FAULT_FALLBACK;
return VM_FAULT_OOM;
if (unlikely(khugepaged_enter(vma, vma->vm_flags)))
return VM_FAULT_OOM;
- if (!(flags & FAULT_FLAG_WRITE) && !mm_forbids_zeropage(mm) &&
+ if (!(fe->flags & FAULT_FLAG_WRITE) &&
+ !mm_forbids_zeropage(vma->vm_mm) &&
transparent_hugepage_use_zero_page()) {
- spinlock_t *ptl;
pgtable_t pgtable;
struct page *zero_page;
bool set;
int ret;
- pgtable = pte_alloc_one(mm, haddr);
+ pgtable = pte_alloc_one(vma->vm_mm, haddr);
if (unlikely(!pgtable))
return VM_FAULT_OOM;
zero_page = get_huge_zero_page();
if (unlikely(!zero_page)) {
- pte_free(mm, pgtable);
+ pte_free(vma->vm_mm, pgtable);
count_vm_event(THP_FAULT_FALLBACK);
return VM_FAULT_FALLBACK;
}
- ptl = pmd_lock(mm, pmd);
+ fe->ptl = pmd_lock(vma->vm_mm, fe->pmd);
ret = 0;
set = false;
- if (pmd_none(*pmd)) {
+ if (pmd_none(*fe->pmd)) {
if (userfaultfd_missing(vma)) {
- spin_unlock(ptl);
- ret = handle_userfault(vma, address, flags,
- VM_UFFD_MISSING);
+ spin_unlock(fe->ptl);
+ ret = handle_userfault(fe, VM_UFFD_MISSING);
VM_BUG_ON(ret & VM_FAULT_FALLBACK);
} else {
- set_huge_zero_page(pgtable, mm, vma,
- haddr, pmd,
- zero_page);
- spin_unlock(ptl);
+ set_huge_zero_page(pgtable, vma->vm_mm, vma,
+ haddr, fe->pmd, zero_page);
+ spin_unlock(fe->ptl);
set = true;
}
} else
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
if (!set) {
- pte_free(mm, pgtable);
+ pte_free(vma->vm_mm, pgtable);
put_huge_zero_page();
}
return ret;
return VM_FAULT_FALLBACK;
}
prep_transhuge_page(page);
- return __do_huge_pmd_anonymous_page(mm, vma, address, pmd, page, gfp,
- flags);
+ return __do_huge_pmd_anonymous_page(fe, page, gfp);
}
static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
struct page *src_page;
pmd_t pmd;
pgtable_t pgtable = NULL;
- int ret;
+ int ret = -ENOMEM;
- if (!vma_is_dax(vma)) {
- ret = -ENOMEM;
- pgtable = pte_alloc_one(dst_mm, addr);
- if (unlikely(!pgtable))
- goto out;
- }
+ /* Skip if can be re-fill on fault */
+ if (!vma_is_anonymous(vma))
+ return 0;
+
+ pgtable = pte_alloc_one(dst_mm, addr);
+ if (unlikely(!pgtable))
+ goto out;
dst_ptl = pmd_lock(dst_mm, dst_pmd);
src_ptl = pmd_lockptr(src_mm, src_pmd);
ret = -EAGAIN;
pmd = *src_pmd;
- if (unlikely(!pmd_trans_huge(pmd) && !pmd_devmap(pmd))) {
+ if (unlikely(!pmd_trans_huge(pmd))) {
pte_free(dst_mm, pgtable);
goto out_unlock;
}
goto out_unlock;
}
- if (!vma_is_dax(vma)) {
- /* thp accounting separate from pmd_devmap accounting */
- src_page = pmd_page(pmd);
- VM_BUG_ON_PAGE(!PageHead(src_page), src_page);
- get_page(src_page);
- page_dup_rmap(src_page, true);
- add_mm_counter(dst_mm, MM_ANONPAGES, HPAGE_PMD_NR);
- atomic_long_inc(&dst_mm->nr_ptes);
- pgtable_trans_huge_deposit(dst_mm, dst_pmd, pgtable);
- }
+ src_page = pmd_page(pmd);
+ VM_BUG_ON_PAGE(!PageHead(src_page), src_page);
+ get_page(src_page);
+ page_dup_rmap(src_page, true);
+ add_mm_counter(dst_mm, MM_ANONPAGES, HPAGE_PMD_NR);
+ atomic_long_inc(&dst_mm->nr_ptes);
+ pgtable_trans_huge_deposit(dst_mm, dst_pmd, pgtable);
pmdp_set_wrprotect(src_mm, addr, src_pmd);
pmd = pmd_mkold(pmd_wrprotect(pmd));
return ret;
}
-void huge_pmd_set_accessed(struct mm_struct *mm,
- struct vm_area_struct *vma,
- unsigned long address,
- pmd_t *pmd, pmd_t orig_pmd,
- int dirty)
+void huge_pmd_set_accessed(struct fault_env *fe, pmd_t orig_pmd)
{
- spinlock_t *ptl;
pmd_t entry;
unsigned long haddr;
- ptl = pmd_lock(mm, pmd);
- if (unlikely(!pmd_same(*pmd, orig_pmd)))
+ fe->ptl = pmd_lock(fe->vma->vm_mm, fe->pmd);
+ if (unlikely(!pmd_same(*fe->pmd, orig_pmd)))
goto unlock;
entry = pmd_mkyoung(orig_pmd);
- haddr = address & HPAGE_PMD_MASK;
- if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
- update_mmu_cache_pmd(vma, address, pmd);
+ haddr = fe->address & HPAGE_PMD_MASK;
+ if (pmdp_set_access_flags(fe->vma, haddr, fe->pmd, entry,
+ fe->flags & FAULT_FLAG_WRITE))
+ update_mmu_cache_pmd(fe->vma, fe->address, fe->pmd);
unlock:
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
}
-static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
- struct vm_area_struct *vma,
- unsigned long address,
- pmd_t *pmd, pmd_t orig_pmd,
- struct page *page,
- unsigned long haddr)
+static int do_huge_pmd_wp_page_fallback(struct fault_env *fe, pmd_t orig_pmd,
+ struct page *page)
{
+ struct vm_area_struct *vma = fe->vma;
+ unsigned long haddr = fe->address & HPAGE_PMD_MASK;
struct mem_cgroup *memcg;
- spinlock_t *ptl;
pgtable_t pgtable;
pmd_t _pmd;
int ret = 0, i;
for (i = 0; i < HPAGE_PMD_NR; i++) {
pages[i] = alloc_page_vma_node(GFP_HIGHUSER_MOVABLE |
- __GFP_OTHER_NODE,
- vma, address, page_to_nid(page));
+ __GFP_OTHER_NODE, vma,
+ fe->address, page_to_nid(page));
if (unlikely(!pages[i] ||
- mem_cgroup_try_charge(pages[i], mm, GFP_KERNEL,
- &memcg, false))) {
+ mem_cgroup_try_charge(pages[i], vma->vm_mm,
+ GFP_KERNEL, &memcg, false))) {
if (pages[i])
put_page(pages[i]);
while (--i >= 0) {
mmun_start = haddr;
mmun_end = haddr + HPAGE_PMD_SIZE;
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(vma->vm_mm, mmun_start, mmun_end);
- ptl = pmd_lock(mm, pmd);
- if (unlikely(!pmd_same(*pmd, orig_pmd)))
+ fe->ptl = pmd_lock(vma->vm_mm, fe->pmd);
+ if (unlikely(!pmd_same(*fe->pmd, orig_pmd)))
goto out_free_pages;
VM_BUG_ON_PAGE(!PageHead(page), page);
- pmdp_huge_clear_flush_notify(vma, haddr, pmd);
+ pmdp_huge_clear_flush_notify(vma, haddr, fe->pmd);
/* leave pmd empty until pte is filled */
- pgtable = pgtable_trans_huge_withdraw(mm, pmd);
- pmd_populate(mm, &_pmd, pgtable);
+ pgtable = pgtable_trans_huge_withdraw(vma->vm_mm, fe->pmd);
+ pmd_populate(vma->vm_mm, &_pmd, pgtable);
for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) {
- pte_t *pte, entry;
+ pte_t entry;
entry = mk_pte(pages[i], vma->vm_page_prot);
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
memcg = (void *)page_private(pages[i]);
set_page_private(pages[i], 0);
- page_add_new_anon_rmap(pages[i], vma, haddr, false);
+ page_add_new_anon_rmap(pages[i], fe->vma, haddr, false);
mem_cgroup_commit_charge(pages[i], memcg, false, false);
lru_cache_add_active_or_unevictable(pages[i], vma);
- pte = pte_offset_map(&_pmd, haddr);
- VM_BUG_ON(!pte_none(*pte));
- set_pte_at(mm, haddr, pte, entry);
- pte_unmap(pte);
+ fe->pte = pte_offset_map(&_pmd, haddr);
+ VM_BUG_ON(!pte_none(*fe->pte));
+ set_pte_at(vma->vm_mm, haddr, fe->pte, entry);
+ pte_unmap(fe->pte);
}
kfree(pages);
smp_wmb(); /* make pte visible before pmd */
- pmd_populate(mm, pmd, pgtable);
+ pmd_populate(vma->vm_mm, fe->pmd, pgtable);
page_remove_rmap(page, true);
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(vma->vm_mm, mmun_start, mmun_end);
ret |= VM_FAULT_WRITE;
put_page(page);
return ret;
out_free_pages:
- spin_unlock(ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ spin_unlock(fe->ptl);
+ mmu_notifier_invalidate_range_end(vma->vm_mm, mmun_start, mmun_end);
for (i = 0; i < HPAGE_PMD_NR; i++) {
memcg = (void *)page_private(pages[i]);
set_page_private(pages[i], 0);
goto out;
}
-int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
- unsigned long address, pmd_t *pmd, pmd_t orig_pmd)
+int do_huge_pmd_wp_page(struct fault_env *fe, pmd_t orig_pmd)
{
- spinlock_t *ptl;
- int ret = 0;
+ struct vm_area_struct *vma = fe->vma;
struct page *page = NULL, *new_page;
struct mem_cgroup *memcg;
- unsigned long haddr;
+ unsigned long haddr = fe->address & HPAGE_PMD_MASK;
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
gfp_t huge_gfp; /* for allocation and charge */
+ int ret = 0;
- ptl = pmd_lockptr(mm, pmd);
+ fe->ptl = pmd_lockptr(vma->vm_mm, fe->pmd);
VM_BUG_ON_VMA(!vma->anon_vma, vma);
- haddr = address & HPAGE_PMD_MASK;
if (is_huge_zero_pmd(orig_pmd))
goto alloc;
- spin_lock(ptl);
- if (unlikely(!pmd_same(*pmd, orig_pmd)))
+ spin_lock(fe->ptl);
+ if (unlikely(!pmd_same(*fe->pmd, orig_pmd)))
goto out_unlock;
page = pmd_page(orig_pmd);
pmd_t entry;
entry = pmd_mkyoung(orig_pmd);
entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
- if (pmdp_set_access_flags(vma, haddr, pmd, entry, 1))
- update_mmu_cache_pmd(vma, address, pmd);
+ if (pmdp_set_access_flags(vma, haddr, fe->pmd, entry, 1))
+ update_mmu_cache_pmd(vma, fe->address, fe->pmd);
ret |= VM_FAULT_WRITE;
goto out_unlock;
}
get_page(page);
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
alloc:
if (transparent_hugepage_enabled(vma) &&
!transparent_hugepage_debug_cow()) {
prep_transhuge_page(new_page);
} else {
if (!page) {
- split_huge_pmd(vma, pmd, address);
+ split_huge_pmd(vma, fe->pmd, fe->address);
ret |= VM_FAULT_FALLBACK;
} else {
- ret = do_huge_pmd_wp_page_fallback(mm, vma, address,
- pmd, orig_pmd, page, haddr);
+ ret = do_huge_pmd_wp_page_fallback(fe, orig_pmd, page);
if (ret & VM_FAULT_OOM) {
- split_huge_pmd(vma, pmd, address);
+ split_huge_pmd(vma, fe->pmd, fe->address);
ret |= VM_FAULT_FALLBACK;
}
put_page(page);
goto out;
}
- if (unlikely(mem_cgroup_try_charge(new_page, mm, huge_gfp, &memcg,
- true))) {
+ if (unlikely(mem_cgroup_try_charge(new_page, vma->vm_mm,
+ huge_gfp, &memcg, true))) {
put_page(new_page);
- if (page) {
- split_huge_pmd(vma, pmd, address);
+ split_huge_pmd(vma, fe->pmd, fe->address);
+ if (page)
put_page(page);
- } else
- split_huge_pmd(vma, pmd, address);
ret |= VM_FAULT_FALLBACK;
count_vm_event(THP_FAULT_FALLBACK);
goto out;
mmun_start = haddr;
mmun_end = haddr + HPAGE_PMD_SIZE;
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(vma->vm_mm, mmun_start, mmun_end);
- spin_lock(ptl);
+ spin_lock(fe->ptl);
if (page)
put_page(page);
- if (unlikely(!pmd_same(*pmd, orig_pmd))) {
- spin_unlock(ptl);
+ if (unlikely(!pmd_same(*fe->pmd, orig_pmd))) {
+ spin_unlock(fe->ptl);
mem_cgroup_cancel_charge(new_page, memcg, true);
put_page(new_page);
goto out_mn;
pmd_t entry;
entry = mk_huge_pmd(new_page, vma->vm_page_prot);
entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
- pmdp_huge_clear_flush_notify(vma, haddr, pmd);
+ pmdp_huge_clear_flush_notify(vma, haddr, fe->pmd);
page_add_new_anon_rmap(new_page, vma, haddr, true);
mem_cgroup_commit_charge(new_page, memcg, false, true);
lru_cache_add_active_or_unevictable(new_page, vma);
- set_pmd_at(mm, haddr, pmd, entry);
- update_mmu_cache_pmd(vma, address, pmd);
+ set_pmd_at(vma->vm_mm, haddr, fe->pmd, entry);
+ update_mmu_cache_pmd(vma, fe->address, fe->pmd);
if (!page) {
- add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
+ add_mm_counter(vma->vm_mm, MM_ANONPAGES, HPAGE_PMD_NR);
put_huge_zero_page();
} else {
VM_BUG_ON_PAGE(!PageHead(page), page);
}
ret |= VM_FAULT_WRITE;
}
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
out_mn:
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(vma->vm_mm, mmun_start, mmun_end);
out:
return ret;
out_unlock:
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
return ret;
}
* We don't mlock() pte-mapped THPs. This way we can avoid
* leaking mlocked pages into non-VM_LOCKED VMAs.
*
+ * For anon THP:
+ *
* In most cases the pmd is the only mapping of the page as we
* break COW for the mlock() -- see gup_flags |= FOLL_WRITE for
* writable private mappings in populate_vma_page_range().
* The only scenario when we have the page shared here is if we
* mlocking read-only mapping shared over fork(). We skip
* mlocking such pages.
+ *
+ * For file THP:
+ *
+ * We can expect PageDoubleMap() to be stable under page lock:
+ * for file pages we set it in page_add_file_rmap(), which
+ * requires page to be locked.
*/
- if (compound_mapcount(page) == 1 && !PageDoubleMap(page) &&
- page->mapping && trylock_page(page)) {
- lru_add_drain();
- if (page->mapping)
- mlock_vma_page(page);
- unlock_page(page);
- }
+
+ if (PageAnon(page) && compound_mapcount(page) != 1)
+ goto skip_mlock;
+ if (PageDoubleMap(page) || !page->mapping)
+ goto skip_mlock;
+ if (!trylock_page(page))
+ goto skip_mlock;
+ lru_add_drain();
+ if (page->mapping && !PageDoubleMap(page))
+ mlock_vma_page(page);
+ unlock_page(page);
}
+skip_mlock:
page += (addr & ~HPAGE_PMD_MASK) >> PAGE_SHIFT;
VM_BUG_ON_PAGE(!PageCompound(page), page);
if (flags & FOLL_GET)
}
/* NUMA hinting page fault entry point for trans huge pmds */
-int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
- unsigned long addr, pmd_t pmd, pmd_t *pmdp)
+int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t pmd)
{
- spinlock_t *ptl;
+ struct vm_area_struct *vma = fe->vma;
struct anon_vma *anon_vma = NULL;
struct page *page;
- unsigned long haddr = addr & HPAGE_PMD_MASK;
+ unsigned long haddr = fe->address & HPAGE_PMD_MASK;
int page_nid = -1, this_nid = numa_node_id();
int target_nid, last_cpupid = -1;
bool page_locked;
/* A PROT_NONE fault should not end up here */
BUG_ON(!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)));
- ptl = pmd_lock(mm, pmdp);
- if (unlikely(!pmd_same(pmd, *pmdp)))
+ fe->ptl = pmd_lock(vma->vm_mm, fe->pmd);
+ if (unlikely(!pmd_same(pmd, *fe->pmd)))
goto out_unlock;
/*
* without disrupting NUMA hinting information. Do not relock and
* check_same as the page may no longer be mapped.
*/
- if (unlikely(pmd_trans_migrating(*pmdp))) {
- page = pmd_page(*pmdp);
- spin_unlock(ptl);
+ if (unlikely(pmd_trans_migrating(*fe->pmd))) {
+ page = pmd_page(*fe->pmd);
+ spin_unlock(fe->ptl);
wait_on_page_locked(page);
goto out;
}
/* Migration could have started since the pmd_trans_migrating check */
if (!page_locked) {
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
wait_on_page_locked(page);
page_nid = -1;
goto out;
* to serialises splits
*/
get_page(page);
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
anon_vma = page_lock_anon_vma_read(page);
/* Confirm the PMD did not change while page_table_lock was released */
- spin_lock(ptl);
- if (unlikely(!pmd_same(pmd, *pmdp))) {
+ spin_lock(fe->ptl);
+ if (unlikely(!pmd_same(pmd, *fe->pmd))) {
unlock_page(page);
put_page(page);
page_nid = -1;
* Migrate the THP to the requested node, returns with page unlocked
* and access rights restored.
*/
- spin_unlock(ptl);
- migrated = migrate_misplaced_transhuge_page(mm, vma,
- pmdp, pmd, addr, page, target_nid);
+ spin_unlock(fe->ptl);
+ migrated = migrate_misplaced_transhuge_page(vma->vm_mm, vma,
+ fe->pmd, pmd, fe->address, page, target_nid);
if (migrated) {
flags |= TNF_MIGRATED;
page_nid = target_nid;
pmd = pmd_mkyoung(pmd);
if (was_writable)
pmd = pmd_mkwrite(pmd);
- set_pmd_at(mm, haddr, pmdp, pmd);
- update_mmu_cache_pmd(vma, addr, pmdp);
+ set_pmd_at(vma->vm_mm, haddr, fe->pmd, pmd);
+ update_mmu_cache_pmd(vma, fe->address, fe->pmd);
unlock_page(page);
out_unlock:
- spin_unlock(ptl);
+ spin_unlock(fe->ptl);
out:
if (anon_vma)
page_unlock_anon_vma_read(anon_vma);
if (page_nid != -1)
- task_numa_fault(last_cpupid, page_nid, HPAGE_PMD_NR, flags);
+ task_numa_fault(last_cpupid, page_nid, HPAGE_PMD_NR, fe->flags);
return 0;
}
if (next - addr != HPAGE_PMD_SIZE) {
get_page(page);
spin_unlock(ptl);
- if (split_huge_page(page)) {
- put_page(page);
- unlock_page(page);
- goto out_unlocked;
- }
+ split_huge_page(page);
put_page(page);
unlock_page(page);
- ret = 1;
goto out_unlocked;
}
struct page *page = pmd_page(orig_pmd);
page_remove_rmap(page, true);
VM_BUG_ON_PAGE(page_mapcount(page) < 0, page);
- add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
VM_BUG_ON_PAGE(!PageHead(page), page);
- pte_free(tlb->mm, pgtable_trans_huge_withdraw(tlb->mm, pmd));
- atomic_long_dec(&tlb->mm->nr_ptes);
+ if (PageAnon(page)) {
+ pgtable_t pgtable;
+ pgtable = pgtable_trans_huge_withdraw(tlb->mm, pmd);
+ pte_free(tlb->mm, pgtable);
+ atomic_long_dec(&tlb->mm->nr_ptes);
+ add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
+ } else {
+ add_mm_counter(tlb->mm, MM_FILEPAGES, -HPAGE_PMD_NR);
+ }
spin_unlock(ptl);
- tlb_remove_page(tlb, page);
+ tlb_remove_page_size(tlb, page, HPAGE_PMD_SIZE);
}
return 1;
}
entry = pmd_mkwrite(entry);
ret = HPAGE_PMD_NR;
set_pmd_at(mm, addr, pmd, entry);
- BUG_ON(!preserve_write && pmd_write(entry));
+ BUG_ON(vma_is_anonymous(vma) && !preserve_write &&
+ pmd_write(entry));
}
spin_unlock(ptl);
}
return !(vma->vm_flags & VM_NO_THP);
}
+/*
+ * If mmap_sem temporarily dropped, revalidate vma
+ * before taking mmap_sem.
+ * Return 0 if succeeds, otherwise return none-zero
+ * value (scan code).
+ */
+
+static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address)
+{
+ struct vm_area_struct *vma;
+ unsigned long hstart, hend;
+
+ if (unlikely(khugepaged_test_exit(mm)))
+ return SCAN_ANY_PROCESS;
+
+ vma = find_vma(mm, address);
+ if (!vma)
+ return SCAN_VMA_NULL;
+
+ hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
+ hend = vma->vm_end & HPAGE_PMD_MASK;
+ if (address < hstart || address + HPAGE_PMD_SIZE > hend)
+ return SCAN_ADDRESS_RANGE;
+ if (!hugepage_vma_check(vma))
+ return SCAN_VMA_CHECK;
+ return 0;
+}
+
+/*
+ * Bring missing pages in from swap, to complete THP collapse.
+ * Only done if khugepaged_scan_pmd believes it is worthwhile.
+ *
+ * Called and returns without pte mapped or spinlocks held,
+ * but with mmap_sem held to protect against vma changes.
+ */
+
+static bool __collapse_huge_page_swapin(struct mm_struct *mm,
+ struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmd)
+{
+ pte_t pteval;
+ int swapped_in = 0, ret = 0;
+ struct fault_env fe = {
+ .vma = vma,
+ .address = address,
+ .flags = FAULT_FLAG_ALLOW_RETRY,
+ .pmd = pmd,
+ };
+
+ fe.pte = pte_offset_map(pmd, address);
+ for (; fe.address < address + HPAGE_PMD_NR*PAGE_SIZE;
+ fe.pte++, fe.address += PAGE_SIZE) {
+ pteval = *fe.pte;
+ if (!is_swap_pte(pteval))
+ continue;
+ swapped_in++;
+ ret = do_swap_page(&fe, pteval);
+ /* do_swap_page returns VM_FAULT_RETRY with released mmap_sem */
+ if (ret & VM_FAULT_RETRY) {
+ down_read(&mm->mmap_sem);
+ /* vma is no longer available, don't continue to swapin */
+ if (hugepage_vma_revalidate(mm, address))
+ return false;
+ /* check if the pmd is still valid */
+ if (mm_find_pmd(mm, address) != pmd)
+ return false;
+ }
+ if (ret & VM_FAULT_ERROR) {
+ trace_mm_collapse_huge_page_swapin(mm, swapped_in, 0);
+ return false;
+ }
+ /* pte is unmapped now, we need to map it */
+ fe.pte = pte_offset_map(pmd, fe.address);
+ }
+ fe.pte--;
+ pte_unmap(fe.pte);
+ trace_mm_collapse_huge_page_swapin(mm, swapped_in, 1);
+ return true;
+}
+
static void collapse_huge_page(struct mm_struct *mm,
unsigned long address,
struct page **hpage,
struct page *new_page;
spinlock_t *pmd_ptl, *pte_ptl;
int isolated = 0, result = 0;
- unsigned long hstart, hend;
struct mem_cgroup *memcg;
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
goto out_nolock;
}
+ down_read(&mm->mmap_sem);
+ result = hugepage_vma_revalidate(mm, address);
+ if (result) {
+ mem_cgroup_cancel_charge(new_page, memcg, true);
+ up_read(&mm->mmap_sem);
+ goto out_nolock;
+ }
+
+ pmd = mm_find_pmd(mm, address);
+ if (!pmd) {
+ result = SCAN_PMD_NULL;
+ mem_cgroup_cancel_charge(new_page, memcg, true);
+ up_read(&mm->mmap_sem);
+ goto out_nolock;
+ }
+
+ /*
+ * __collapse_huge_page_swapin always returns with mmap_sem locked.
+ * If it fails, release mmap_sem and jump directly out.
+ * Continuing to collapse causes inconsistency.
+ */
+ if (!__collapse_huge_page_swapin(mm, vma, address, pmd)) {
+ mem_cgroup_cancel_charge(new_page, memcg, true);
+ up_read(&mm->mmap_sem);
+ goto out_nolock;
+ }
+
+ up_read(&mm->mmap_sem);
/*
* Prevent all access to pagetables with the exception of
- * gup_fast later hanlded by the ptep_clear_flush and the VM
+ * gup_fast later handled by the ptep_clear_flush and the VM
* handled by the anon_vma lock + PG_lock.
*/
down_write(&mm->mmap_sem);
- if (unlikely(khugepaged_test_exit(mm))) {
- result = SCAN_ANY_PROCESS;
- goto out;
- }
-
- vma = find_vma(mm, address);
- if (!vma) {
- result = SCAN_VMA_NULL;
- goto out;
- }
- hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
- hend = vma->vm_end & HPAGE_PMD_MASK;
- if (address < hstart || address + HPAGE_PMD_SIZE > hend) {
- result = SCAN_ADDRESS_RANGE;
+ result = hugepage_vma_revalidate(mm, address);
+ if (result)
goto out;
- }
- if (!hugepage_vma_check(vma)) {
- result = SCAN_VMA_CHECK;
- goto out;
- }
- pmd = mm_find_pmd(mm, address);
- if (!pmd) {
- result = SCAN_PMD_NULL;
+ /* check if the pmd is still valid */
+ if (mm_find_pmd(mm, address) != pmd)
goto out;
- }
anon_vma_lock_write(vma->anon_vma);
result = SCAN_SUCCEED;
out_up_write:
up_write(&mm->mmap_sem);
- trace_mm_collapse_huge_page(mm, isolated, result);
- return;
-
out_nolock:
trace_mm_collapse_huge_page(mm, isolated, result);
return;
struct page *page = NULL;
unsigned long _address;
spinlock_t *ptl;
- int node = NUMA_NO_NODE;
+ int node = NUMA_NO_NODE, unmapped = 0;
bool writable = false, referenced = false;
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
for (_address = address, _pte = pte; _pte < pte+HPAGE_PMD_NR;
_pte++, _address += PAGE_SIZE) {
pte_t pteval = *_pte;
+ if (is_swap_pte(pteval)) {
+ if (++unmapped <= khugepaged_max_ptes_swap) {
+ continue;
+ } else {
+ result = SCAN_EXCEED_SWAP_PTE;
+ goto out_unmap;
+ }
+ }
if (pte_none(pteval) || is_zero_pfn(pte_pfn(pteval))) {
if (!userfaultfd_armed(vma) &&
++none_or_zero <= khugepaged_max_ptes_none) {
}
out:
trace_mm_khugepaged_scan_pmd(mm, page, writable, referenced,
- none_or_zero, result);
+ none_or_zero, result, unmapped);
return ret;
}
count_vm_event(THP_SPLIT_PMD);
- if (vma_is_dax(vma)) {
- pmd_t _pmd = pmdp_huge_clear_flush_notify(vma, haddr, pmd);
+ if (!vma_is_anonymous(vma)) {
+ _pmd = pmdp_huge_clear_flush_notify(vma, haddr, pmd);
if (is_huge_zero_pmd(_pmd))
put_huge_zero_page();
+ if (vma_is_dax(vma))
+ return;
+ page = pmd_page(_pmd);
+ if (!PageReferenced(page) && pmd_young(_pmd))
+ SetPageReferenced(page);
+ page_remove_rmap(page, true);
+ put_page(page);
+ add_mm_counter(mm, MM_FILEPAGES, -HPAGE_PMD_NR);
return;
} else if (is_huge_zero_pmd(*pmd)) {
return __split_huge_zero_page_pmd(vma, haddr, pmd);
if (atomic_add_negative(-1, compound_mapcount_ptr(page))) {
/* Last compound_mapcount is gone. */
- __dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES);
+ __dec_zone_page_state(page, NR_ANON_THPS);
if (TestClearPageDoubleMap(page)) {
/* No need in mapcount reference anymore */
for (i = 0; i < HPAGE_PMD_NR; i++)
}
void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
- unsigned long address, bool freeze)
+ unsigned long address, bool freeze, struct page *page)
{
spinlock_t *ptl;
struct mm_struct *mm = vma->vm_mm;
mmu_notifier_invalidate_range_start(mm, haddr, haddr + HPAGE_PMD_SIZE);
ptl = pmd_lock(mm, pmd);
+
+ /*
+ * If caller asks to setup a migration entries, we need a page to check
+ * pmd against. Otherwise we can end up replacing wrong page.
+ */
+ VM_BUG_ON(freeze && !page);
+ if (page && page != pmd_page(*pmd))
+ goto out;
+
if (pmd_trans_huge(*pmd)) {
- struct page *page = pmd_page(*pmd);
+ page = pmd_page(*pmd);
if (PageMlocked(page))
clear_page_mlock(page);
} else if (!pmd_devmap(*pmd))
return;
pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd) || (!pmd_trans_huge(*pmd) && !pmd_devmap(*pmd)))
- return;
- /*
- * If caller asks to setup a migration entries, we need a page to check
- * pmd against. Otherwise we can end up replacing wrong page.
- */
- VM_BUG_ON(freeze && !page);
- if (page && page != pmd_page(*pmd))
- return;
-
- /*
- * 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);
+ __split_huge_pmd(vma, pmd, address, freeze, page);
}
void vma_adjust_trans_huge(struct vm_area_struct *vma,
static void freeze_page(struct page *page)
{
- enum ttu_flags ttu_flags = TTU_MIGRATION | TTU_IGNORE_MLOCK |
- TTU_IGNORE_ACCESS | TTU_RMAP_LOCKED;
+ enum ttu_flags ttu_flags = TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS |
+ TTU_RMAP_LOCKED;
int i, ret;
VM_BUG_ON_PAGE(!PageHead(page), page);
+ if (PageAnon(page))
+ ttu_flags |= TTU_MIGRATION;
+
/* We only need TTU_SPLIT_HUGE_PMD once */
ret = try_to_unmap(page, ttu_flags | TTU_SPLIT_HUGE_PMD);
for (i = 1; !ret && i < HPAGE_PMD_NR; i++) {
ret = try_to_unmap(page + i, ttu_flags);
}
- VM_BUG_ON(ret);
+ VM_BUG_ON_PAGE(ret, page + i - 1);
}
static void unfreeze_page(struct page *page)
/*
* 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
+ * tail_page. If we used atomic_set() below instead of atomic_inc() or
+ * 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_inc().
+ * it's safer to use atomic_inc()/atomic_add().
*/
- page_ref_inc(page_tail);
+ if (PageAnon(head)) {
+ page_ref_inc(page_tail);
+ } else {
+ /* Additional pin to radix tree */
+ page_ref_add(page_tail, 2);
+ }
page_tail->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
page_tail->flags |= (head->flags &
lru_add_page_tail(head, page_tail, lruvec, list);
}
-static void __split_huge_page(struct page *page, struct list_head *list)
+static void __split_huge_page(struct page *page, struct list_head *list,
+ unsigned long flags)
{
struct page *head = compound_head(page);
struct zone *zone = page_zone(head);
struct lruvec *lruvec;
+ pgoff_t end = -1;
int i;
- /* prevent PageLRU to go away from under us, and freeze lru stats */
- spin_lock_irq(&zone->lru_lock);
lruvec = mem_cgroup_page_lruvec(head, zone);
/* complete memcg works before add pages to LRU */
mem_cgroup_split_huge_fixup(head);
- for (i = HPAGE_PMD_NR - 1; i >= 1; i--)
+ if (!PageAnon(page))
+ end = DIV_ROUND_UP(i_size_read(head->mapping->host), PAGE_SIZE);
+
+ for (i = HPAGE_PMD_NR - 1; i >= 1; i--) {
__split_huge_page_tail(head, i, lruvec, list);
+ /* Some pages can be beyond i_size: drop them from page cache */
+ if (head[i].index >= end) {
+ __ClearPageDirty(head + i);
+ __delete_from_page_cache(head + i, NULL);
+ if (IS_ENABLED(CONFIG_SHMEM) && PageSwapBacked(head))
+ shmem_uncharge(head->mapping->host, 1);
+ put_page(head + i);
+ }
+ }
ClearPageCompound(head);
- spin_unlock_irq(&zone->lru_lock);
+ /* See comment in __split_huge_page_tail() */
+ if (PageAnon(head)) {
+ page_ref_inc(head);
+ } else {
+ /* Additional pin to radix tree */
+ page_ref_add(head, 2);
+ spin_unlock(&head->mapping->tree_lock);
+ }
+
+ spin_unlock_irqrestore(&page_zone(head)->lru_lock, flags);
unfreeze_page(head);
int total_mapcount(struct page *page)
{
- int i, ret;
+ int i, compound, ret;
VM_BUG_ON_PAGE(PageTail(page), page);
if (likely(!PageCompound(page)))
return atomic_read(&page->_mapcount) + 1;
- ret = compound_mapcount(page);
+ compound = compound_mapcount(page);
if (PageHuge(page))
- return ret;
+ return compound;
+ ret = compound;
for (i = 0; i < HPAGE_PMD_NR; i++)
ret += atomic_read(&page[i]._mapcount) + 1;
+ /* File pages has compound_mapcount included in _mapcount */
+ if (!PageAnon(page))
+ return ret - compound * HPAGE_PMD_NR;
if (PageDoubleMap(page))
ret -= HPAGE_PMD_NR;
return ret;
{
struct page *head = compound_head(page);
struct pglist_data *pgdata = NODE_DATA(page_to_nid(head));
- struct anon_vma *anon_vma;
- int count, mapcount, ret;
+ struct anon_vma *anon_vma = NULL;
+ struct address_space *mapping = NULL;
+ int count, mapcount, extra_pins, ret;
bool mlocked;
unsigned long flags;
VM_BUG_ON_PAGE(is_huge_zero_page(page), page);
- VM_BUG_ON_PAGE(!PageAnon(page), page);
VM_BUG_ON_PAGE(!PageLocked(page), page);
VM_BUG_ON_PAGE(!PageSwapBacked(page), page);
VM_BUG_ON_PAGE(!PageCompound(page), page);
- /*
- * The caller does not necessarily hold an mmap_sem that would prevent
- * the anon_vma disappearing so we first we take a reference to it
- * and then lock the anon_vma for write. This is similar to
- * page_lock_anon_vma_read except the write lock is taken to serialise
- * against parallel split or collapse operations.
- */
- anon_vma = page_get_anon_vma(head);
- if (!anon_vma) {
- ret = -EBUSY;
- goto out;
+ if (PageAnon(head)) {
+ /*
+ * The caller does not necessarily hold an mmap_sem that would
+ * prevent the anon_vma disappearing so we first we take a
+ * reference to it and then lock the anon_vma for write. This
+ * is similar to page_lock_anon_vma_read except the write lock
+ * is taken to serialise against parallel split or collapse
+ * operations.
+ */
+ anon_vma = page_get_anon_vma(head);
+ if (!anon_vma) {
+ ret = -EBUSY;
+ goto out;
+ }
+ extra_pins = 0;
+ mapping = NULL;
+ anon_vma_lock_write(anon_vma);
+ } else {
+ mapping = head->mapping;
+
+ /* Truncated ? */
+ if (!mapping) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ /* Addidional pins from radix tree */
+ extra_pins = HPAGE_PMD_NR;
+ anon_vma = NULL;
+ i_mmap_lock_read(mapping);
}
- anon_vma_lock_write(anon_vma);
/*
* Racy check if we can split the page, before freeze_page() will
* split PMDs
*/
- if (total_mapcount(head) != page_count(head) - 1) {
+ if (total_mapcount(head) != page_count(head) - extra_pins - 1) {
ret = -EBUSY;
goto out_unlock;
}
if (mlocked)
lru_add_drain();
+ /* prevent PageLRU to go away from under us, and freeze lru stats */
+ spin_lock_irqsave(&page_zone(head)->lru_lock, flags);
+
+ if (mapping) {
+ void **pslot;
+
+ spin_lock(&mapping->tree_lock);
+ pslot = radix_tree_lookup_slot(&mapping->page_tree,
+ page_index(head));
+ /*
+ * Check if the head page is present in radix tree.
+ * We assume all tail are present too, if head is there.
+ */
+ if (radix_tree_deref_slot_protected(pslot,
+ &mapping->tree_lock) != head)
+ goto fail;
+ }
+
/* Prevent deferred_split_scan() touching ->_refcount */
- spin_lock_irqsave(&pgdata->split_queue_lock, flags);
+ spin_lock(&pgdata->split_queue_lock);
count = page_count(head);
mapcount = total_mapcount(head);
- if (!mapcount && count == 1) {
+ if (!mapcount && page_ref_freeze(head, 1 + extra_pins)) {
if (!list_empty(page_deferred_list(head))) {
pgdata->split_queue_len--;
list_del(page_deferred_list(head));
}
- spin_unlock_irqrestore(&pgdata->split_queue_lock, flags);
- __split_huge_page(page, list);
+ if (mapping)
+ __dec_zone_page_state(page, NR_SHMEM_THPS);
+ spin_unlock(&pgdata->split_queue_lock);
+ __split_huge_page(page, list, flags);
ret = 0;
- } else if (IS_ENABLED(CONFIG_DEBUG_VM) && mapcount) {
- spin_unlock_irqrestore(&pgdata->split_queue_lock, flags);
- pr_alert("total_mapcount: %u, page_count(): %u\n",
- mapcount, count);
- if (PageTail(page))
- dump_page(head, NULL);
- dump_page(page, "total_mapcount(head) > 0");
- BUG();
} else {
- spin_unlock_irqrestore(&pgdata->split_queue_lock, flags);
+ if (IS_ENABLED(CONFIG_DEBUG_VM) && mapcount) {
+ pr_alert("total_mapcount: %u, page_count(): %u\n",
+ mapcount, count);
+ if (PageTail(page))
+ dump_page(head, NULL);
+ dump_page(page, "total_mapcount(head) > 0");
+ BUG();
+ }
+ spin_unlock(&pgdata->split_queue_lock);
+fail: if (mapping)
+ spin_unlock(&mapping->tree_lock);
+ spin_unlock_irqrestore(&page_zone(head)->lru_lock, flags);
unfreeze_page(head);
ret = -EBUSY;
}
out_unlock:
- anon_vma_unlock_write(anon_vma);
- put_anon_vma(anon_vma);
+ if (anon_vma) {
+ anon_vma_unlock_write(anon_vma);
+ put_anon_vma(anon_vma);
+ }
+ if (mapping)
+ i_mmap_unlock_read(mapping);
out:
count_vm_event(!ret ? THP_SPLIT_PAGE : THP_SPLIT_PAGE_FAILED);
return ret;
if (zone != page_zone(page))
goto next;
- if (!PageHead(page) || !PageAnon(page) ||
- PageHuge(page))
+ if (!PageHead(page) || PageHuge(page) || !PageLRU(page))
goto next;
total++;