From: Mel Gorman <mgorman@xxxxxxx>
The global variable page_group_by_mobility_disabled remembers if page grouping
by mobility was disabled at boot time. It's more efficient to do this by jump
label.
Signed-off-by: Mel Gorman <mgorman@xxxxxxx>
---
include/linux/gfp.h | 2 +-
include/linux/mmzone.h | 7 ++++++-
mm/page_alloc.c | 15 ++++++---------
3 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 6d3a2d430715..5a27bbba63ed 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -151,7 +151,7 @@ static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
{
WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
- if (unlikely(page_group_by_mobility_disabled))
+ if (page_group_by_mobility_disabled())
return MIGRATE_UNMOVABLE;
/* Group based on mobility */
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 672ac437c43c..c9497519340a 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -73,7 +73,12 @@ enum {
for (order = 0; order < MAX_ORDER; order++) \
for (type = 0; type < MIGRATE_TYPES; type++)
-extern int page_group_by_mobility_disabled;
+extern struct static_key page_group_by_mobility_key;
+
+static inline bool page_group_by_mobility_disabled(void)
+{
+ return static_key_false(&page_group_by_mobility_key);
+}
#define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1)
#define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 56432b59b797..403cf31f8cf9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -228,7 +228,7 @@ EXPORT_SYMBOL(nr_node_ids);
EXPORT_SYMBOL(nr_online_nodes);
#endif
-int page_group_by_mobility_disabled __read_mostly;
+struct static_key page_group_by_mobility_key __read_mostly = STATIC_KEY_INIT_FALSE;
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
static inline void reset_deferred_meminit(pg_data_t *pgdat)
@@ -303,8 +303,7 @@ static inline bool update_defer_init(pg_data_t *pgdat,
void set_pageblock_migratetype(struct page *page, int migratetype)
{
- if (unlikely(page_group_by_mobility_disabled &&
- migratetype < MIGRATE_PCPTYPES))
+ if (page_group_by_mobility_disabled() && migratetype < MIGRATE_PCPTYPES)
migratetype = MIGRATE_UNMOVABLE;
set_pageblock_flags_group(page, (unsigned long)migratetype,
@@ -1501,7 +1500,7 @@ static bool can_steal_fallback(unsigned int order, int start_mt)
if (order >= pageblock_order / 2 ||
start_mt == MIGRATE_RECLAIMABLE ||
start_mt == MIGRATE_UNMOVABLE ||
- page_group_by_mobility_disabled)
+ page_group_by_mobility_disabled())
return true;
return false;
@@ -1530,7 +1529,7 @@ static void steal_suitable_fallback(struct zone *zone, struct page *page,
/* Claim the whole block if over half of it is free */
if (pages >= (1 << (pageblock_order-1)) ||
- page_group_by_mobility_disabled)
+ page_group_by_mobility_disabled())
set_pageblock_migratetype(page, start_type);
}
@@ -4156,15 +4155,13 @@ void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone)
* disabled and enable it later
*/
if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
- page_group_by_mobility_disabled = 1;
- else
- page_group_by_mobility_disabled = 0;
+ static_key_slow_inc(&page_group_by_mobility_key);
pr_info("Built %i zonelists in %s order, mobility grouping %s. "
"Total pages: %ld\n",
nr_online_nodes,
zonelist_order_name[current_zonelist_order],
- page_group_by_mobility_disabled ? "off" : "on",
+ page_group_by_mobility_disabled() ? "off" : "on",
vm_total_pages);
#ifdef CONFIG_NUMA
pr_info("Policy zone: %s\n", zone_names[policy_zone]);
--
2.4.3
--
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