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-rw-r--r--mm/migrate.c89
1 files changed, 45 insertions, 44 deletions
diff --git a/mm/migrate.c b/mm/migrate.c
index 9194375b2307..a8025befc323 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -72,28 +72,12 @@ int migrate_prep_local(void)
}
/*
- * Add isolated pages on the list back to the LRU under page lock
- * to avoid leaking evictable pages back onto unevictable list.
- */
-void putback_lru_pages(struct list_head *l)
-{
- struct page *page;
- struct page *page2;
-
- list_for_each_entry_safe(page, page2, l, lru) {
- list_del(&page->lru);
- dec_zone_page_state(page, NR_ISOLATED_ANON +
- page_is_file_cache(page));
- putback_lru_page(page);
- }
-}
-
-/*
* Put previously isolated pages back onto the appropriate lists
* from where they were once taken off for compaction/migration.
*
- * This function shall be used instead of putback_lru_pages(),
- * whenever the isolated pageset has been built by isolate_migratepages_range()
+ * This function shall be used whenever the isolated pageset has been
+ * built from lru, balloon, hugetlbfs page. See isolate_migratepages_range()
+ * and isolate_huge_page().
*/
void putback_movable_pages(struct list_head *l)
{
@@ -199,7 +183,12 @@ out:
*/
static void remove_migration_ptes(struct page *old, struct page *new)
{
- rmap_walk(new, remove_migration_pte, old);
+ struct rmap_walk_control rwc = {
+ .rmap_one = remove_migration_pte,
+ .arg = old,
+ };
+
+ rmap_walk(new, &rwc);
}
/*
@@ -563,14 +552,6 @@ void migrate_page_copy(struct page *newpage, struct page *page)
* Migration functions
***********************************************************/
-/* Always fail migration. Used for mappings that are not movable */
-int fail_migrate_page(struct address_space *mapping,
- struct page *newpage, struct page *page)
-{
- return -EIO;
-}
-EXPORT_SYMBOL(fail_migrate_page);
-
/*
* Common logic to directly migrate a single page suitable for
* pages that do not use PagePrivate/PagePrivate2.
@@ -1008,7 +989,7 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
{
int rc = 0;
int *result = NULL;
- struct page *new_hpage = get_new_page(hpage, private, &result);
+ struct page *new_hpage;
struct anon_vma *anon_vma = NULL;
/*
@@ -1018,9 +999,12 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
* tables or check whether the hugepage is pmd-based or not before
* kicking migration.
*/
- if (!hugepage_migration_support(page_hstate(hpage)))
+ if (!hugepage_migration_support(page_hstate(hpage))) {
+ putback_active_hugepage(hpage);
return -ENOSYS;
+ }
+ new_hpage = get_new_page(hpage, private, &result);
if (!new_hpage)
return -ENOMEM;
@@ -1120,7 +1104,12 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
nr_succeeded++;
break;
default:
- /* Permanent failure */
+ /*
+ * Permanent failure (-EBUSY, -ENOSYS, etc.):
+ * unlike -EAGAIN case, the failed page is
+ * removed from migration page list and not
+ * retried in the next outer loop.
+ */
nr_failed++;
break;
}
@@ -1594,31 +1583,38 @@ bool migrate_ratelimited(int node)
}
/* Returns true if the node is migrate rate-limited after the update */
-bool numamigrate_update_ratelimit(pg_data_t *pgdat, unsigned long nr_pages)
+static bool numamigrate_update_ratelimit(pg_data_t *pgdat,
+ unsigned long nr_pages)
{
- bool rate_limited = false;
-
/*
* 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!
*/
- spin_lock(&pgdat->numabalancing_migrate_lock);
if (time_after(jiffies, pgdat->numabalancing_migrate_next_window)) {
+ spin_lock(&pgdat->numabalancing_migrate_lock);
pgdat->numabalancing_migrate_nr_pages = 0;
pgdat->numabalancing_migrate_next_window = jiffies +
msecs_to_jiffies(migrate_interval_millisecs);
+ spin_unlock(&pgdat->numabalancing_migrate_lock);
}
- if (pgdat->numabalancing_migrate_nr_pages > ratelimit_pages)
- rate_limited = true;
- else
- pgdat->numabalancing_migrate_nr_pages += nr_pages;
- spin_unlock(&pgdat->numabalancing_migrate_lock);
-
- return rate_limited;
+ if (pgdat->numabalancing_migrate_nr_pages > ratelimit_pages) {
+ trace_mm_numa_migrate_ratelimit(current, pgdat->node_id,
+ nr_pages);
+ return true;
+ }
+
+ /*
+ * This is an unlocked non-atomic update so errors are possible.
+ * The consequences are failing to migrate when we potentiall should
+ * have which is not severe enough to warrant locking. If it is ever
+ * a problem, it can be converted to a per-cpu counter.
+ */
+ pgdat->numabalancing_migrate_nr_pages += nr_pages;
+ return false;
}
-int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
+static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
{
int page_lru;
@@ -1705,7 +1701,12 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_page,
node, MIGRATE_ASYNC, MR_NUMA_MISPLACED);
if (nr_remaining) {
- putback_lru_pages(&migratepages);
+ if (!list_empty(&migratepages)) {
+ list_del(&page->lru);
+ dec_zone_page_state(page, NR_ISOLATED_ANON +
+ page_is_file_cache(page));
+ putback_lru_page(page);
+ }
isolated = 0;
} else
count_vm_numa_event(NUMA_PAGE_MIGRATE);