Mel Gorman | 748446b | 2010-05-24 14:32:27 -0700 | [diff] [blame] | 1 | #ifndef _LINUX_COMPACTION_H |
| 2 | #define _LINUX_COMPACTION_H |
| 3 | |
Mel Gorman | 56de726 | 2010-05-24 14:32:30 -0700 | [diff] [blame] | 4 | /* Return values for compact_zone() and try_to_compact_pages() */ |
| 5 | /* compaction didn't start as it was not possible or direct reclaim was more suitable */ |
| 6 | #define COMPACT_SKIPPED 0 |
| 7 | /* compaction should continue to another pageblock */ |
| 8 | #define COMPACT_CONTINUE 1 |
| 9 | /* direct compaction partially compacted a zone and there are suitable pages */ |
| 10 | #define COMPACT_PARTIAL 2 |
| 11 | /* The full zone was compacted */ |
| 12 | #define COMPACT_COMPLETE 3 |
Mel Gorman | 748446b | 2010-05-24 14:32:27 -0700 | [diff] [blame] | 13 | |
Mel Gorman | 76ab0f5 | 2010-05-24 14:32:28 -0700 | [diff] [blame] | 14 | #ifdef CONFIG_COMPACTION |
| 15 | extern int sysctl_compact_memory; |
| 16 | extern int sysctl_compaction_handler(struct ctl_table *table, int write, |
| 17 | void __user *buffer, size_t *length, loff_t *ppos); |
Mel Gorman | 5e77190 | 2010-05-24 14:32:31 -0700 | [diff] [blame] | 18 | extern int sysctl_extfrag_threshold; |
| 19 | extern int sysctl_extfrag_handler(struct ctl_table *table, int write, |
| 20 | void __user *buffer, size_t *length, loff_t *ppos); |
Mel Gorman | 56de726 | 2010-05-24 14:32:30 -0700 | [diff] [blame] | 21 | |
| 22 | extern int fragmentation_index(struct zone *zone, unsigned int order); |
| 23 | extern unsigned long try_to_compact_pages(struct zonelist *zonelist, |
Mel Gorman | 77f1fe6 | 2011-01-13 15:45:57 -0800 | [diff] [blame] | 24 | int order, gfp_t gfp_mask, nodemask_t *mask, |
Mel Gorman | 47ecfcb | 2013-01-11 09:27:01 +0000 | [diff] [blame] | 25 | bool sync, bool *contended); |
Rik van Riel | 7be62de | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 26 | extern int compact_pgdat(pg_data_t *pgdat, int order); |
Mel Gorman | 6299702 | 2012-10-08 16:32:47 -0700 | [diff] [blame] | 27 | extern void reset_isolation_suitable(pg_data_t *pgdat); |
Mel Gorman | 3e7d344 | 2011-01-13 15:45:56 -0800 | [diff] [blame] | 28 | extern unsigned long compaction_suitable(struct zone *zone, int order); |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 29 | |
| 30 | /* Do not skip compaction more than 64 times */ |
| 31 | #define COMPACT_MAX_DEFER_SHIFT 6 |
| 32 | |
| 33 | /* |
| 34 | * Compaction is deferred when compaction fails to result in a page |
| 35 | * allocation success. 1 << compact_defer_limit compactions are skipped up |
| 36 | * to a limit of 1 << COMPACT_MAX_DEFER_SHIFT |
| 37 | */ |
Rik van Riel | aff6224 | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 38 | static inline void defer_compaction(struct zone *zone, int order) |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 39 | { |
| 40 | zone->compact_considered = 0; |
| 41 | zone->compact_defer_shift++; |
| 42 | |
Rik van Riel | aff6224 | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 43 | if (order < zone->compact_order_failed) |
| 44 | zone->compact_order_failed = order; |
| 45 | |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 46 | if (zone->compact_defer_shift > COMPACT_MAX_DEFER_SHIFT) |
| 47 | zone->compact_defer_shift = COMPACT_MAX_DEFER_SHIFT; |
| 48 | } |
| 49 | |
| 50 | /* Returns true if compaction should be skipped this time */ |
Rik van Riel | aff6224 | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 51 | static inline bool compaction_deferred(struct zone *zone, int order) |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 52 | { |
| 53 | unsigned long defer_limit = 1UL << zone->compact_defer_shift; |
| 54 | |
Rik van Riel | aff6224 | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 55 | if (order < zone->compact_order_failed) |
| 56 | return false; |
| 57 | |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 58 | /* Avoid possible overflow */ |
| 59 | if (++zone->compact_considered > defer_limit) |
| 60 | zone->compact_considered = defer_limit; |
| 61 | |
Gavin Shan | c59e261 | 2012-07-31 16:42:49 -0700 | [diff] [blame] | 62 | return zone->compact_considered < defer_limit; |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 63 | } |
| 64 | |
Mel Gorman | 6299702 | 2012-10-08 16:32:47 -0700 | [diff] [blame] | 65 | /* Returns true if restarting compaction after many failures */ |
| 66 | static inline bool compaction_restarting(struct zone *zone, int order) |
| 67 | { |
| 68 | if (order < zone->compact_order_failed) |
| 69 | return false; |
| 70 | |
| 71 | return zone->compact_defer_shift == COMPACT_MAX_DEFER_SHIFT && |
| 72 | zone->compact_considered >= 1UL << zone->compact_defer_shift; |
| 73 | } |
| 74 | |
Mel Gorman | 56de726 | 2010-05-24 14:32:30 -0700 | [diff] [blame] | 75 | #else |
| 76 | static inline unsigned long try_to_compact_pages(struct zonelist *zonelist, |
Mel Gorman | 77f1fe6 | 2011-01-13 15:45:57 -0800 | [diff] [blame] | 77 | int order, gfp_t gfp_mask, nodemask_t *nodemask, |
Mel Gorman | 47ecfcb | 2013-01-11 09:27:01 +0000 | [diff] [blame] | 78 | bool sync, bool *contended) |
Mel Gorman | 56de726 | 2010-05-24 14:32:30 -0700 | [diff] [blame] | 79 | { |
| 80 | return COMPACT_CONTINUE; |
| 81 | } |
| 82 | |
Rik van Riel | 7be62de | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 83 | static inline int compact_pgdat(pg_data_t *pgdat, int order) |
| 84 | { |
| 85 | return COMPACT_CONTINUE; |
| 86 | } |
| 87 | |
Mel Gorman | 6299702 | 2012-10-08 16:32:47 -0700 | [diff] [blame] | 88 | static inline void reset_isolation_suitable(pg_data_t *pgdat) |
| 89 | { |
| 90 | } |
| 91 | |
Mel Gorman | 3e7d344 | 2011-01-13 15:45:56 -0800 | [diff] [blame] | 92 | static inline unsigned long compaction_suitable(struct zone *zone, int order) |
| 93 | { |
| 94 | return COMPACT_SKIPPED; |
| 95 | } |
| 96 | |
Rik van Riel | aff6224 | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 97 | static inline void defer_compaction(struct zone *zone, int order) |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 98 | { |
| 99 | } |
| 100 | |
Rik van Riel | aff6224 | 2012-03-21 16:33:52 -0700 | [diff] [blame] | 101 | static inline bool compaction_deferred(struct zone *zone, int order) |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 102 | { |
Gavin Shan | c59e261 | 2012-07-31 16:42:49 -0700 | [diff] [blame] | 103 | return true; |
Mel Gorman | 4f92e25 | 2010-05-24 14:32:32 -0700 | [diff] [blame] | 104 | } |
| 105 | |
Mel Gorman | 76ab0f5 | 2010-05-24 14:32:28 -0700 | [diff] [blame] | 106 | #endif /* CONFIG_COMPACTION */ |
| 107 | |
Mel Gorman | ed4a6d7 | 2010-05-24 14:32:29 -0700 | [diff] [blame] | 108 | #if defined(CONFIG_COMPACTION) && defined(CONFIG_SYSFS) && defined(CONFIG_NUMA) |
| 109 | extern int compaction_register_node(struct node *node); |
| 110 | extern void compaction_unregister_node(struct node *node); |
| 111 | |
| 112 | #else |
| 113 | |
| 114 | static inline int compaction_register_node(struct node *node) |
| 115 | { |
| 116 | return 0; |
| 117 | } |
| 118 | |
| 119 | static inline void compaction_unregister_node(struct node *node) |
| 120 | { |
| 121 | } |
| 122 | #endif /* CONFIG_COMPACTION && CONFIG_SYSFS && CONFIG_NUMA */ |
| 123 | |
Mel Gorman | 748446b | 2010-05-24 14:32:27 -0700 | [diff] [blame] | 124 | #endif /* _LINUX_COMPACTION_H */ |