1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _MM_PERCPU_INTERNAL_H 3 #define _MM_PERCPU_INTERNAL_H 4 5 #include <linux/types.h> 6 #include <linux/percpu.h> 7 #include <linux/memcontrol.h> 8 9 /* 10 * pcpu_block_md is the metadata block struct. 11 * Each chunk's bitmap is split into a number of full blocks. 12 * All units are in terms of bits. 13 * 14 * The scan hint is the largest known contiguous area before the contig hint. 15 * It is not necessarily the actual largest contig hint though. There is an 16 * invariant that the scan_hint_start > contig_hint_start iff 17 * scan_hint == contig_hint. This is necessary because when scanning forward, 18 * we don't know if a new contig hint would be better than the current one. 19 */ 20 struct pcpu_block_md { 21 int scan_hint; /* scan hint for block */ 22 int scan_hint_start; /* block relative starting 23 position of the scan hint */ 24 int contig_hint; /* contig hint for block */ 25 int contig_hint_start; /* block relative starting 26 position of the contig hint */ 27 int left_free; /* size of free space along 28 the left side of the block */ 29 int right_free; /* size of free space along 30 the right side of the block */ 31 int first_free; /* block position of first free */ 32 int nr_bits; /* total bits responsible for */ 33 }; 34 35 struct pcpuobj_ext { 36 #ifdef CONFIG_MEMCG_KMEM 37 struct obj_cgroup *cgroup; 38 #endif 39 #ifdef CONFIG_MEM_ALLOC_PROFILING 40 union codetag_ref tag; 41 #endif 42 }; 43 44 #if defined(CONFIG_MEMCG_KMEM) || defined(CONFIG_MEM_ALLOC_PROFILING) 45 #define NEED_PCPUOBJ_EXT 46 #endif 47 48 struct pcpu_chunk { 49 #ifdef CONFIG_PERCPU_STATS 50 int nr_alloc; /* # of allocations */ 51 size_t max_alloc_size; /* largest allocation size */ 52 #endif 53 54 struct list_head list; /* linked to pcpu_slot lists */ 55 int free_bytes; /* free bytes in the chunk */ 56 struct pcpu_block_md chunk_md; 57 unsigned long *bound_map; /* boundary map */ 58 59 /* 60 * base_addr is the base address of this chunk. 61 * To reduce false sharing, current layout is optimized to make sure 62 * base_addr locate in the different cacheline with free_bytes and 63 * chunk_md. 64 */ 65 void *base_addr ____cacheline_aligned_in_smp; 66 67 unsigned long *alloc_map; /* allocation map */ 68 struct pcpu_block_md *md_blocks; /* metadata blocks */ 69 70 void *data; /* chunk data */ 71 bool immutable; /* no [de]population allowed */ 72 bool isolated; /* isolated from active chunk 73 slots */ 74 int start_offset; /* the overlap with the previous 75 region to have a page aligned 76 base_addr */ 77 int end_offset; /* additional area required to 78 have the region end page 79 aligned */ 80 #ifdef NEED_PCPUOBJ_EXT 81 struct pcpuobj_ext *obj_exts; /* vector of object cgroups */ 82 #endif 83 84 int nr_pages; /* # of pages served by this chunk */ 85 int nr_populated; /* # of populated pages */ 86 int nr_empty_pop_pages; /* # of empty populated pages */ 87 unsigned long populated[]; /* populated bitmap */ 88 }; 89 90 static inline bool need_pcpuobj_ext(void) 91 { 92 if (IS_ENABLED(CONFIG_MEM_ALLOC_PROFILING)) 93 return true; 94 if (!mem_cgroup_kmem_disabled()) 95 return true; 96 return false; 97 } 98 99 extern spinlock_t pcpu_lock; 100 101 extern struct list_head *pcpu_chunk_lists; 102 extern int pcpu_nr_slots; 103 extern int pcpu_sidelined_slot; 104 extern int pcpu_to_depopulate_slot; 105 extern int pcpu_nr_empty_pop_pages; 106 107 extern struct pcpu_chunk *pcpu_first_chunk; 108 extern struct pcpu_chunk *pcpu_reserved_chunk; 109 110 /** 111 * pcpu_chunk_nr_blocks - converts nr_pages to # of md_blocks 112 * @chunk: chunk of interest 113 * 114 * This conversion is from the number of physical pages that the chunk 115 * serves to the number of bitmap blocks used. 116 */ 117 static inline int pcpu_chunk_nr_blocks(struct pcpu_chunk *chunk) 118 { 119 return chunk->nr_pages * PAGE_SIZE / PCPU_BITMAP_BLOCK_SIZE; 120 } 121 122 /** 123 * pcpu_nr_pages_to_map_bits - converts the pages to size of bitmap 124 * @pages: number of physical pages 125 * 126 * This conversion is from physical pages to the number of bits 127 * required in the bitmap. 128 */ 129 static inline int pcpu_nr_pages_to_map_bits(int pages) 130 { 131 return pages * PAGE_SIZE / PCPU_MIN_ALLOC_SIZE; 132 } 133 134 /** 135 * pcpu_chunk_map_bits - helper to convert nr_pages to size of bitmap 136 * @chunk: chunk of interest 137 * 138 * This conversion is from the number of physical pages that the chunk 139 * serves to the number of bits in the bitmap. 140 */ 141 static inline int pcpu_chunk_map_bits(struct pcpu_chunk *chunk) 142 { 143 return pcpu_nr_pages_to_map_bits(chunk->nr_pages); 144 } 145 146 /** 147 * pcpu_obj_full_size - helper to calculate size of each accounted object 148 * @size: size of area to allocate in bytes 149 * 150 * For each accounted object there is an extra space which is used to store 151 * obj_cgroup membership if kmemcg is not disabled. Charge it too. 152 */ 153 static inline size_t pcpu_obj_full_size(size_t size) 154 { 155 size_t extra_size = 0; 156 157 #ifdef CONFIG_MEMCG_KMEM 158 if (!mem_cgroup_kmem_disabled()) 159 extra_size += size / PCPU_MIN_ALLOC_SIZE * sizeof(struct obj_cgroup *); 160 #endif 161 162 return size * num_possible_cpus() + extra_size; 163 } 164 165 #ifdef CONFIG_PERCPU_STATS 166 167 #include <linux/spinlock.h> 168 169 struct percpu_stats { 170 u64 nr_alloc; /* lifetime # of allocations */ 171 u64 nr_dealloc; /* lifetime # of deallocations */ 172 u64 nr_cur_alloc; /* current # of allocations */ 173 u64 nr_max_alloc; /* max # of live allocations */ 174 u32 nr_chunks; /* current # of live chunks */ 175 u32 nr_max_chunks; /* max # of live chunks */ 176 size_t min_alloc_size; /* min allocation size */ 177 size_t max_alloc_size; /* max allocation size */ 178 }; 179 180 extern struct percpu_stats pcpu_stats; 181 extern struct pcpu_alloc_info pcpu_stats_ai; 182 183 /* 184 * For debug purposes. We don't care about the flexible array. 185 */ 186 static inline void pcpu_stats_save_ai(const struct pcpu_alloc_info *ai) 187 { 188 memcpy(&pcpu_stats_ai, ai, sizeof(struct pcpu_alloc_info)); 189 190 /* initialize min_alloc_size to unit_size */ 191 pcpu_stats.min_alloc_size = pcpu_stats_ai.unit_size; 192 } 193 194 /* 195 * pcpu_stats_area_alloc - increment area allocation stats 196 * @chunk: the location of the area being allocated 197 * @size: size of area to allocate in bytes 198 * 199 * CONTEXT: 200 * pcpu_lock. 201 */ 202 static inline void pcpu_stats_area_alloc(struct pcpu_chunk *chunk, size_t size) 203 { 204 lockdep_assert_held(&pcpu_lock); 205 206 pcpu_stats.nr_alloc++; 207 pcpu_stats.nr_cur_alloc++; 208 pcpu_stats.nr_max_alloc = 209 max(pcpu_stats.nr_max_alloc, pcpu_stats.nr_cur_alloc); 210 pcpu_stats.min_alloc_size = 211 min(pcpu_stats.min_alloc_size, size); 212 pcpu_stats.max_alloc_size = 213 max(pcpu_stats.max_alloc_size, size); 214 215 chunk->nr_alloc++; 216 chunk->max_alloc_size = max(chunk->max_alloc_size, size); 217 } 218 219 /* 220 * pcpu_stats_area_dealloc - decrement allocation stats 221 * @chunk: the location of the area being deallocated 222 * 223 * CONTEXT: 224 * pcpu_lock. 225 */ 226 static inline void pcpu_stats_area_dealloc(struct pcpu_chunk *chunk) 227 { 228 lockdep_assert_held(&pcpu_lock); 229 230 pcpu_stats.nr_dealloc++; 231 pcpu_stats.nr_cur_alloc--; 232 233 chunk->nr_alloc--; 234 } 235 236 /* 237 * pcpu_stats_chunk_alloc - increment chunk stats 238 */ 239 static inline void pcpu_stats_chunk_alloc(void) 240 { 241 unsigned long flags; 242 spin_lock_irqsave(&pcpu_lock, flags); 243 244 pcpu_stats.nr_chunks++; 245 pcpu_stats.nr_max_chunks = 246 max(pcpu_stats.nr_max_chunks, pcpu_stats.nr_chunks); 247 248 spin_unlock_irqrestore(&pcpu_lock, flags); 249 } 250 251 /* 252 * pcpu_stats_chunk_dealloc - decrement chunk stats 253 */ 254 static inline void pcpu_stats_chunk_dealloc(void) 255 { 256 unsigned long flags; 257 spin_lock_irqsave(&pcpu_lock, flags); 258 259 pcpu_stats.nr_chunks--; 260 261 spin_unlock_irqrestore(&pcpu_lock, flags); 262 } 263 264 #else 265 266 static inline void pcpu_stats_save_ai(const struct pcpu_alloc_info *ai) 267 { 268 } 269 270 static inline void pcpu_stats_area_alloc(struct pcpu_chunk *chunk, size_t size) 271 { 272 } 273 274 static inline void pcpu_stats_area_dealloc(struct pcpu_chunk *chunk) 275 { 276 } 277 278 static inline void pcpu_stats_chunk_alloc(void) 279 { 280 } 281 282 static inline void pcpu_stats_chunk_dealloc(void) 283 { 284 } 285 286 #endif /* !CONFIG_PERCPU_STATS */ 287 288 #endif 289