xref: /freebsd/contrib/jemalloc/include/jemalloc/internal/base.h (revision c43cad87172039ccf38172129c79755ea79e6102)
1 #ifndef JEMALLOC_INTERNAL_BASE_H
2 #define JEMALLOC_INTERNAL_BASE_H
3 
4 #include "jemalloc/internal/edata.h"
5 #include "jemalloc/internal/ehooks.h"
6 #include "jemalloc/internal/mutex.h"
7 
8 enum metadata_thp_mode_e {
9 	metadata_thp_disabled   = 0,
10 	/*
11 	 * Lazily enable hugepage for metadata. To avoid high RSS caused by THP
12 	 * + low usage arena (i.e. THP becomes a significant percentage), the
13 	 * "auto" option only starts using THP after a base allocator used up
14 	 * the first THP region.  Starting from the second hugepage (in a single
15 	 * arena), "auto" behaves the same as "always", i.e. madvise hugepage
16 	 * right away.
17 	 */
18 	metadata_thp_auto       = 1,
19 	metadata_thp_always     = 2,
20 	metadata_thp_mode_limit = 3
21 };
22 typedef enum metadata_thp_mode_e metadata_thp_mode_t;
23 
24 #define METADATA_THP_DEFAULT metadata_thp_disabled
25 extern metadata_thp_mode_t opt_metadata_thp;
26 extern const char *metadata_thp_mode_names[];
27 
28 
29 /* Embedded at the beginning of every block of base-managed virtual memory. */
30 typedef struct base_block_s base_block_t;
31 struct base_block_s {
32 	/* Total size of block's virtual memory mapping. */
33 	size_t size;
34 
35 	/* Next block in list of base's blocks. */
36 	base_block_t *next;
37 
38 	/* Tracks unused trailing space. */
39 	edata_t edata;
40 };
41 
42 typedef struct base_s base_t;
43 struct base_s {
44 	/*
45 	 * User-configurable extent hook functions.
46 	 */
47 	ehooks_t ehooks;
48 
49 	/*
50 	 * User-configurable extent hook functions for metadata allocations.
51 	 */
52 	ehooks_t ehooks_base;
53 
54 	/* Protects base_alloc() and base_stats_get() operations. */
55 	malloc_mutex_t mtx;
56 
57 	/* Using THP when true (metadata_thp auto mode). */
58 	bool auto_thp_switched;
59 	/*
60 	 * Most recent size class in the series of increasingly large base
61 	 * extents.  Logarithmic spacing between subsequent allocations ensures
62 	 * that the total number of distinct mappings remains small.
63 	 */
64 	pszind_t pind_last;
65 
66 	/* Serial number generation state. */
67 	size_t extent_sn_next;
68 
69 	/* Chain of all blocks associated with base. */
70 	base_block_t *blocks;
71 
72 	/* Heap of extents that track unused trailing space within blocks. */
73 	edata_heap_t avail[SC_NSIZES];
74 
75 	/* Stats, only maintained if config_stats. */
76 	size_t allocated;
77 	size_t resident;
78 	size_t mapped;
79 	/* Number of THP regions touched. */
80 	size_t n_thp;
81 };
82 
83 static inline unsigned
84 base_ind_get(const base_t *base) {
85 	return ehooks_ind_get(&base->ehooks);
86 }
87 
88 static inline bool
89 metadata_thp_enabled(void) {
90 	return (opt_metadata_thp != metadata_thp_disabled);
91 }
92 
93 base_t *b0get(void);
94 base_t *base_new(tsdn_t *tsdn, unsigned ind,
95     const extent_hooks_t *extent_hooks, bool metadata_use_hooks);
96 void base_delete(tsdn_t *tsdn, base_t *base);
97 ehooks_t *base_ehooks_get(base_t *base);
98 ehooks_t *base_ehooks_get_for_metadata(base_t *base);
99 extent_hooks_t *base_extent_hooks_set(base_t *base,
100     extent_hooks_t *extent_hooks);
101 void *base_alloc(tsdn_t *tsdn, base_t *base, size_t size, size_t alignment);
102 edata_t *base_alloc_edata(tsdn_t *tsdn, base_t *base);
103 void base_stats_get(tsdn_t *tsdn, base_t *base, size_t *allocated,
104     size_t *resident, size_t *mapped, size_t *n_thp);
105 void base_prefork(tsdn_t *tsdn, base_t *base);
106 void base_postfork_parent(tsdn_t *tsdn, base_t *base);
107 void base_postfork_child(tsdn_t *tsdn, base_t *base);
108 bool base_boot(tsdn_t *tsdn);
109 
110 #endif /* JEMALLOC_INTERNAL_BASE_H */
111