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Diffstat (limited to 'mm/migrate.c')
-rw-r--r--mm/migrate.c180
1 files changed, 121 insertions, 59 deletions
diff --git a/mm/migrate.c b/mm/migrate.c
index 6f0c24438bba..bb940045fe85 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -100,10 +100,14 @@ void putback_movable_pages(struct list_head *l)
struct page *page2;
list_for_each_entry_safe(page, page2, l, lru) {
+ if (unlikely(PageHuge(page))) {
+ putback_active_hugepage(page);
+ continue;
+ }
list_del(&page->lru);
dec_zone_page_state(page, NR_ISOLATED_ANON +
page_is_file_cache(page));
- if (unlikely(balloon_page_movable(page)))
+ if (unlikely(isolated_balloon_page(page)))
balloon_page_putback(page);
else
putback_lru_page(page);
@@ -126,7 +130,7 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma,
ptep = huge_pte_offset(mm, addr);
if (!ptep)
goto out;
- ptl = &mm->page_table_lock;
+ ptl = huge_pte_lockptr(hstate_vma(vma), mm, ptep);
} else {
pmd = mm_find_pmd(mm, addr);
if (!pmd)
@@ -157,6 +161,8 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma,
get_page(new);
pte = pte_mkold(mk_pte(new, vma->vm_page_prot));
+ if (pte_swp_soft_dirty(*ptep))
+ pte = pte_mksoft_dirty(pte);
if (is_write_migration_entry(entry))
pte = pte_mkwrite(pte);
#ifdef CONFIG_HUGETLB_PAGE
@@ -243,9 +249,10 @@ void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd,
__migration_entry_wait(mm, ptep, ptl);
}
-void migration_entry_wait_huge(struct mm_struct *mm, pte_t *pte)
+void migration_entry_wait_huge(struct vm_area_struct *vma,
+ struct mm_struct *mm, pte_t *pte)
{
- spinlock_t *ptl = &(mm)->page_table_lock;
+ spinlock_t *ptl = huge_pte_lockptr(hstate_vma(vma), mm, pte);
__migration_entry_wait(mm, pte, ptl);
}
@@ -307,7 +314,7 @@ static inline bool buffer_migrate_lock_buffers(struct buffer_head *head,
* 2 for pages with a mapping
* 3 for pages with a mapping and PagePrivate/PagePrivate2 set.
*/
-static int migrate_page_move_mapping(struct address_space *mapping,
+int migrate_page_move_mapping(struct address_space *mapping,
struct page *newpage, struct page *page,
struct buffer_head *head, enum migrate_mode mode)
{
@@ -435,10 +442,60 @@ int migrate_huge_page_move_mapping(struct address_space *mapping,
}
/*
+ * Gigantic pages are so large that we do not guarantee that page++ pointer
+ * arithmetic will work across the entire page. We need something more
+ * specialized.
+ */
+static void __copy_gigantic_page(struct page *dst, struct page *src,
+ int nr_pages)
+{
+ int i;
+ struct page *dst_base = dst;
+ struct page *src_base = src;
+
+ for (i = 0; i < nr_pages; ) {
+ cond_resched();
+ copy_highpage(dst, src);
+
+ i++;
+ dst = mem_map_next(dst, dst_base, i);
+ src = mem_map_next(src, src_base, i);
+ }
+}
+
+static void copy_huge_page(struct page *dst, struct page *src)
+{
+ int i;
+ int nr_pages;
+
+ if (PageHuge(src)) {
+ /* hugetlbfs page */
+ struct hstate *h = page_hstate(src);
+ nr_pages = pages_per_huge_page(h);
+
+ if (unlikely(nr_pages > MAX_ORDER_NR_PAGES)) {
+ __copy_gigantic_page(dst, src, nr_pages);
+ return;
+ }
+ } else {
+ /* thp page */
+ BUG_ON(!PageTransHuge(src));
+ nr_pages = hpage_nr_pages(src);
+ }
+
+ for (i = 0; i < nr_pages; i++) {
+ cond_resched();
+ copy_highpage(dst + i, src + i);
+ }
+}
+
+/*
* Copy the page to its new location
*/
void migrate_page_copy(struct page *newpage, struct page *page)
{
+ int cpupid;
+
if (PageHuge(page) || PageTransHuge(page))
copy_huge_page(newpage, page);
else
@@ -475,6 +532,13 @@ void migrate_page_copy(struct page *newpage, struct page *page)
__set_page_dirty_nobuffers(newpage);
}
+ /*
+ * Copy NUMA information to the new page, to prevent over-eager
+ * future migrations of this same page.
+ */
+ cpupid = page_cpupid_xchg_last(page, -1);
+ page_cpupid_xchg_last(newpage, cpupid);
+
mlock_migrate_page(newpage, page);
ksm_migrate_page(newpage, page);
/*
@@ -945,6 +1009,16 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
struct page *new_hpage = get_new_page(hpage, private, &result);
struct anon_vma *anon_vma = NULL;
+ /*
+ * Movability of hugepages depends on architectures and hugepage size.
+ * This check is necessary because some callers of hugepage migration
+ * like soft offline and memory hotremove don't walk through page
+ * tables or check whether the hugepage is pmd-based or not before
+ * kicking migration.
+ */
+ if (!hugepage_migration_support(page_hstate(hpage)))
+ return -ENOSYS;
+
if (!new_hpage)
return -ENOMEM;
@@ -975,6 +1049,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
unlock_page(hpage);
out:
+ if (rc != -EAGAIN)
+ putback_active_hugepage(hpage);
put_page(new_hpage);
if (result) {
if (rc)
@@ -1025,7 +1101,11 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
list_for_each_entry_safe(page, page2, from, lru) {
cond_resched();
- rc = unmap_and_move(get_new_page, private,
+ if (PageHuge(page))
+ rc = unmap_and_move_huge_page(get_new_page,
+ private, page, pass > 2, mode);
+ else
+ rc = unmap_and_move(get_new_page, private,
page, pass > 2, mode);
switch(rc) {
@@ -1058,32 +1138,6 @@ out:
return rc;
}
-int migrate_huge_page(struct page *hpage, new_page_t get_new_page,
- unsigned long private, enum migrate_mode mode)
-{
- int pass, rc;
-
- for (pass = 0; pass < 10; pass++) {
- rc = unmap_and_move_huge_page(get_new_page, private,
- hpage, pass > 2, mode);
- switch (rc) {
- case -ENOMEM:
- goto out;
- case -EAGAIN:
- /* try again */
- cond_resched();
- break;
- case MIGRATEPAGE_SUCCESS:
- goto out;
- default:
- rc = -EIO;
- goto out;
- }
- }
-out:
- return rc;
-}
-
#ifdef CONFIG_NUMA
/*
* Move a list of individual pages
@@ -1108,7 +1162,11 @@ static struct page *new_page_node(struct page *p, unsigned long private,
*result = &pm->status;
- return alloc_pages_exact_node(pm->node,
+ if (PageHuge(p))
+ return alloc_huge_page_node(page_hstate(compound_head(p)),
+ pm->node);
+ else
+ return alloc_pages_exact_node(pm->node,
GFP_HIGHUSER_MOVABLE | GFP_THISNODE, 0);
}
@@ -1168,6 +1226,11 @@ static int do_move_page_to_node_array(struct mm_struct *mm,
!migrate_all)
goto put_and_set;
+ if (PageHuge(page)) {
+ isolate_huge_page(page, &pagelist);
+ goto put_and_set;
+ }
+
err = isolate_lru_page(page);
if (!err) {
list_add_tail(&page->lru, &pagelist);
@@ -1190,7 +1253,7 @@ set_status:
err = migrate_pages(&pagelist, new_page_node,
(unsigned long)pm, MIGRATE_SYNC, MR_SYSCALL);
if (err)
- putback_lru_pages(&pagelist);
+ putback_movable_pages(&pagelist);
}
up_read(&mm->mmap_sem);
@@ -1468,7 +1531,7 @@ static bool migrate_balanced_pgdat(struct pglist_data *pgdat,
if (!populated_zone(zone))
continue;
- if (zone->all_unreclaimable)
+ if (!zone_reclaimable(zone))
continue;
/* Avoid waking kswapd by allocating pages_to_migrate pages. */
@@ -1495,7 +1558,7 @@ static struct page *alloc_misplaced_dst_page(struct page *page,
__GFP_NOWARN) &
~GFP_IOFS, 0);
if (newpage)
- page_nid_xchg_last(newpage, page_nid_last(page));
+ page_cpupid_xchg_last(newpage, page_cpupid_last(page));
return newpage;
}
@@ -1596,7 +1659,8 @@ int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
* node. Caller is expected to have an elevated reference count on
* the page that will be dropped by this function before returning.
*/
-int migrate_misplaced_page(struct page *page, int node)
+int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
+ int node)
{
pg_data_t *pgdat = NODE_DATA(node);
int isolated;
@@ -1604,10 +1668,11 @@ int migrate_misplaced_page(struct page *page, int node)
LIST_HEAD(migratepages);
/*
- * Don't migrate pages that are mapped in multiple processes.
- * TODO: Handle false sharing detection instead of this hammer
+ * Don't migrate file pages that are mapped in multiple processes
+ * with execute permissions as they are probably shared libraries.
*/
- if (page_mapcount(page) != 1)
+ if (page_mapcount(page) != 1 && page_is_file_cache(page) &&
+ (vma->vm_flags & VM_EXEC))
goto out;
/*
@@ -1650,6 +1715,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
unsigned long address,
struct page *page, int node)
{
+ spinlock_t *ptl;
unsigned long haddr = address & HPAGE_PMD_MASK;
pg_data_t *pgdat = NODE_DATA(node);
int isolated = 0;
@@ -1658,13 +1724,6 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
int page_lru = page_is_file_cache(page);
/*
- * Don't migrate pages that are mapped in multiple processes.
- * TODO: Handle false sharing detection instead of this hammer
- */
- if (page_mapcount(page) != 1)
- goto out_dropref;
-
- /*
* Rate-limit the amount of data that is being migrated to a node.
* Optimal placement is no good if the memory bus is saturated and
* all the time is being spent migrating!
@@ -1677,7 +1736,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
if (!new_page)
goto out_fail;
- page_nid_xchg_last(new_page, page_nid_last(page));
+ page_cpupid_xchg_last(new_page, page_cpupid_last(page));
isolated = numamigrate_isolate_page(pgdat, page);
if (!isolated) {
@@ -1696,9 +1755,9 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
WARN_ON(PageLRU(new_page));
/* Recheck the target PMD */
- spin_lock(&mm->page_table_lock);
+ ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_same(*pmd, entry))) {
- spin_unlock(&mm->page_table_lock);
+ spin_unlock(ptl);
/* Reverse changes made by migrate_page_copy() */
if (TestClearPageActive(new_page))
@@ -1710,12 +1769,12 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
unlock_page(new_page);
put_page(new_page); /* Free it */
- unlock_page(page);
+ /* Retake the callers reference and putback on LRU */
+ get_page(page);
putback_lru_page(page);
-
- count_vm_events(PGMIGRATE_FAIL, HPAGE_PMD_NR);
- isolated = 0;
- goto out;
+ mod_zone_page_state(page_zone(page),
+ NR_ISOLATED_ANON + page_lru, -HPAGE_PMD_NR);
+ goto out_fail;
}
/*
@@ -1732,9 +1791,9 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
entry = pmd_mkhuge(entry);
- page_add_new_anon_rmap(new_page, vma, haddr);
-
+ pmdp_clear_flush(vma, haddr, pmd);
set_pmd_at(mm, haddr, pmd, entry);
+ page_add_new_anon_rmap(new_page, vma, haddr);
update_mmu_cache_pmd(vma, address, &entry);
page_remove_rmap(page);
/*
@@ -1743,7 +1802,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
* before it's fully transferred to the new page.
*/
mem_cgroup_end_migration(memcg, page, new_page, true);
- spin_unlock(&mm->page_table_lock);
+ spin_unlock(ptl);
unlock_page(new_page);
unlock_page(page);
@@ -1753,7 +1812,6 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
count_vm_events(PGMIGRATE_SUCCESS, HPAGE_PMD_NR);
count_vm_numa_events(NUMA_PAGE_MIGRATE, HPAGE_PMD_NR);
-out:
mod_zone_page_state(page_zone(page),
NR_ISOLATED_ANON + page_lru,
-HPAGE_PMD_NR);
@@ -1762,6 +1820,10 @@ out:
out_fail:
count_vm_events(PGMIGRATE_FAIL, HPAGE_PMD_NR);
out_dropref:
+ entry = pmd_mknonnuma(entry);
+ set_pmd_at(mm, haddr, pmd, entry);
+ update_mmu_cache_pmd(vma, address, &entry);
+
unlock_page(page);
put_page(page);
return 0;