1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _MM_PERCPU_INTERNAL_H
3 #define _MM_PERCPU_INTERNAL_H
5 #include <linux/types.h>
6 #include <linux/percpu.h>
9 * pcpu_block_md is the metadata block struct.
10 * Each chunk's bitmap is split into a number of full blocks.
11 * All units are in terms of bits.
13 * The scan hint is the largest known contiguous area before the contig hint.
14 * It is not necessarily the actual largest contig hint though. There is an
15 * invariant that the scan_hint_start > contig_hint_start iff
16 * scan_hint == contig_hint. This is necessary because when scanning forward,
17 * we don't know if a new contig hint would be better than the current one.
19 struct pcpu_block_md {
20 int scan_hint; /* scan hint for block */
21 int scan_hint_start; /* block relative starting
22 position of the scan hint */
23 int contig_hint; /* contig hint for block */
24 int contig_hint_start; /* block relative starting
25 position of the contig hint */
26 int left_free; /* size of free space along
27 the left side of the block */
28 int right_free; /* size of free space along
29 the right side of the block */
30 int first_free; /* block position of first free */
34 #ifdef CONFIG_PERCPU_STATS
35 int nr_alloc; /* # of allocations */
36 size_t max_alloc_size; /* largest allocation size */
39 struct list_head list; /* linked to pcpu_slot lists */
40 int free_bytes; /* free bytes in the chunk */
41 int contig_bits; /* max contiguous size hint */
42 int contig_bits_start; /* contig_bits starting
44 void *base_addr; /* base address of this chunk */
46 unsigned long *alloc_map; /* allocation map */
47 unsigned long *bound_map; /* boundary map */
48 struct pcpu_block_md *md_blocks; /* metadata blocks */
50 void *data; /* chunk data */
51 int first_bit; /* no free below this */
52 bool immutable; /* no [de]population allowed */
53 int start_offset; /* the overlap with the previous
54 region to have a page aligned
56 int end_offset; /* additional area required to
57 have the region end page
60 int nr_pages; /* # of pages served by this chunk */
61 int nr_populated; /* # of populated pages */
62 int nr_empty_pop_pages; /* # of empty populated pages */
63 unsigned long populated[]; /* populated bitmap */
66 extern spinlock_t pcpu_lock;
68 extern struct list_head *pcpu_slot;
69 extern int pcpu_nr_slots;
70 extern int pcpu_nr_empty_pop_pages;
72 extern struct pcpu_chunk *pcpu_first_chunk;
73 extern struct pcpu_chunk *pcpu_reserved_chunk;
76 * pcpu_chunk_nr_blocks - converts nr_pages to # of md_blocks
77 * @chunk: chunk of interest
79 * This conversion is from the number of physical pages that the chunk
80 * serves to the number of bitmap blocks used.
82 static inline int pcpu_chunk_nr_blocks(struct pcpu_chunk *chunk)
84 return chunk->nr_pages * PAGE_SIZE / PCPU_BITMAP_BLOCK_SIZE;
88 * pcpu_nr_pages_to_map_bits - converts the pages to size of bitmap
89 * @pages: number of physical pages
91 * This conversion is from physical pages to the number of bits
92 * required in the bitmap.
94 static inline int pcpu_nr_pages_to_map_bits(int pages)
96 return pages * PAGE_SIZE / PCPU_MIN_ALLOC_SIZE;
100 * pcpu_chunk_map_bits - helper to convert nr_pages to size of bitmap
101 * @chunk: chunk of interest
103 * This conversion is from the number of physical pages that the chunk
104 * serves to the number of bits in the bitmap.
106 static inline int pcpu_chunk_map_bits(struct pcpu_chunk *chunk)
108 return pcpu_nr_pages_to_map_bits(chunk->nr_pages);
111 #ifdef CONFIG_PERCPU_STATS
113 #include <linux/spinlock.h>
115 struct percpu_stats {
116 u64 nr_alloc; /* lifetime # of allocations */
117 u64 nr_dealloc; /* lifetime # of deallocations */
118 u64 nr_cur_alloc; /* current # of allocations */
119 u64 nr_max_alloc; /* max # of live allocations */
120 u32 nr_chunks; /* current # of live chunks */
121 u32 nr_max_chunks; /* max # of live chunks */
122 size_t min_alloc_size; /* min allocaiton size */
123 size_t max_alloc_size; /* max allocation size */
126 extern struct percpu_stats pcpu_stats;
127 extern struct pcpu_alloc_info pcpu_stats_ai;
130 * For debug purposes. We don't care about the flexible array.
132 static inline void pcpu_stats_save_ai(const struct pcpu_alloc_info *ai)
134 memcpy(&pcpu_stats_ai, ai, sizeof(struct pcpu_alloc_info));
136 /* initialize min_alloc_size to unit_size */
137 pcpu_stats.min_alloc_size = pcpu_stats_ai.unit_size;
141 * pcpu_stats_area_alloc - increment area allocation stats
142 * @chunk: the location of the area being allocated
143 * @size: size of area to allocate in bytes
148 static inline void pcpu_stats_area_alloc(struct pcpu_chunk *chunk, size_t size)
150 lockdep_assert_held(&pcpu_lock);
152 pcpu_stats.nr_alloc++;
153 pcpu_stats.nr_cur_alloc++;
154 pcpu_stats.nr_max_alloc =
155 max(pcpu_stats.nr_max_alloc, pcpu_stats.nr_cur_alloc);
156 pcpu_stats.min_alloc_size =
157 min(pcpu_stats.min_alloc_size, size);
158 pcpu_stats.max_alloc_size =
159 max(pcpu_stats.max_alloc_size, size);
162 chunk->max_alloc_size = max(chunk->max_alloc_size, size);
166 * pcpu_stats_area_dealloc - decrement allocation stats
167 * @chunk: the location of the area being deallocated
172 static inline void pcpu_stats_area_dealloc(struct pcpu_chunk *chunk)
174 lockdep_assert_held(&pcpu_lock);
176 pcpu_stats.nr_dealloc++;
177 pcpu_stats.nr_cur_alloc--;
183 * pcpu_stats_chunk_alloc - increment chunk stats
185 static inline void pcpu_stats_chunk_alloc(void)
188 spin_lock_irqsave(&pcpu_lock, flags);
190 pcpu_stats.nr_chunks++;
191 pcpu_stats.nr_max_chunks =
192 max(pcpu_stats.nr_max_chunks, pcpu_stats.nr_chunks);
194 spin_unlock_irqrestore(&pcpu_lock, flags);
198 * pcpu_stats_chunk_dealloc - decrement chunk stats
200 static inline void pcpu_stats_chunk_dealloc(void)
203 spin_lock_irqsave(&pcpu_lock, flags);
205 pcpu_stats.nr_chunks--;
207 spin_unlock_irqrestore(&pcpu_lock, flags);
212 static inline void pcpu_stats_save_ai(const struct pcpu_alloc_info *ai)
216 static inline void pcpu_stats_area_alloc(struct pcpu_chunk *chunk, size_t size)
220 static inline void pcpu_stats_area_dealloc(struct pcpu_chunk *chunk)
224 static inline void pcpu_stats_chunk_alloc(void)
228 static inline void pcpu_stats_chunk_dealloc(void)
232 #endif /* !CONFIG_PERCPU_STATS */