From: Mel Gorman <[email protected]> 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 <[email protected]> --- 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
