git://bbs.cooldavid.org / net-next-2.6.git / blame
| Commit | Line | Data |
|---|---|---|
| 748446bb MG |
1 | #ifndef _LINUX_COMPACTION_H |
| 2 | #define _LINUX_COMPACTION_H | |
| 3 | ||
| 56de7263 MG |
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 | |
| 748446bb | 13 | |
| 76ab0f53 MG |
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); | |
| 5e771905 MG |
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); | |
| 56de7263 MG |
21 | |
| 22 | extern int fragmentation_index(struct zone *zone, unsigned int order); | |
| 23 | extern unsigned long try_to_compact_pages(struct zonelist *zonelist, | |
| 24 | int order, gfp_t gfp_mask, nodemask_t *mask); | |
| 4f92e258 MG |
25 | |
| 26 | /* Do not skip compaction more than 64 times */ | |
| 27 | #define COMPACT_MAX_DEFER_SHIFT 6 | |
| 28 | ||
| 29 | /* | |
| 30 | * Compaction is deferred when compaction fails to result in a page | |
| 31 | * allocation success. 1 << compact_defer_limit compactions are skipped up | |
| 32 | * to a limit of 1 << COMPACT_MAX_DEFER_SHIFT | |
| 33 | */ | |
| 34 | static inline void defer_compaction(struct zone *zone) | |
| 35 | { | |
| 36 | zone->compact_considered = 0; | |
| 37 | zone->compact_defer_shift++; | |
| 38 | ||
| 39 | if (zone->compact_defer_shift > COMPACT_MAX_DEFER_SHIFT) | |
| 40 | zone->compact_defer_shift = COMPACT_MAX_DEFER_SHIFT; | |
| 41 | } | |
| 42 | ||
| 43 | /* Returns true if compaction should be skipped this time */ | |
| 44 | static inline bool compaction_deferred(struct zone *zone) | |
| 45 | { | |
| 46 | unsigned long defer_limit = 1UL << zone->compact_defer_shift; | |
| 47 | ||
| 48 | /* Avoid possible overflow */ | |
| 49 | if (++zone->compact_considered > defer_limit) | |
| 50 | zone->compact_considered = defer_limit; | |
| 51 | ||
| 52 | return zone->compact_considered < (1UL << zone->compact_defer_shift); | |
| 53 | } | |
| 54 | ||
| 56de7263 MG |
55 | #else |
| 56 | static inline unsigned long try_to_compact_pages(struct zonelist *zonelist, | |
| 57 | int order, gfp_t gfp_mask, nodemask_t *nodemask) | |
| 58 | { | |
| 59 | return COMPACT_CONTINUE; | |
| 60 | } | |
| 61 | ||
| 4f92e258 MG |
62 | static inline void defer_compaction(struct zone *zone) |
| 63 | { | |
| 64 | } | |
| 65 | ||
| 66 | static inline bool compaction_deferred(struct zone *zone) | |
| 67 | { | |
| 68 | return 1; | |
| 69 | } | |
| 70 | ||
| 76ab0f53 MG |
71 | #endif /* CONFIG_COMPACTION */ |
| 72 | ||
| ed4a6d7f MG |
73 | #if defined(CONFIG_COMPACTION) && defined(CONFIG_SYSFS) && defined(CONFIG_NUMA) |
| 74 | extern int compaction_register_node(struct node *node); | |
| 75 | extern void compaction_unregister_node(struct node *node); | |
| 76 | ||
| 77 | #else | |
| 78 | ||
| 79 | static inline int compaction_register_node(struct node *node) | |
| 80 | { | |
| 81 | return 0; | |
| 82 | } | |
| 83 | ||
| 84 | static inline void compaction_unregister_node(struct node *node) | |
| 85 | { | |
| 86 | } | |
| 87 | #endif /* CONFIG_COMPACTION && CONFIG_SYSFS && CONFIG_NUMA */ | |
| 88 | ||
| 748446bb | 89 | #endif /* _LINUX_COMPACTION_H */ |