1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright 2018 Joyent, Inc. 25 */ 26 27 #ifndef _SYS_KMEM_IMPL_H 28 #define _SYS_KMEM_IMPL_H 29 30 #include <sys/kmem.h> 31 #include <sys/vmem.h> 32 #include <sys/thread.h> 33 #include <sys/t_lock.h> 34 #include <sys/time.h> 35 #include <sys/kstat.h> 36 #include <sys/cpuvar.h> 37 #include <sys/systm.h> 38 #include <vm/page.h> 39 #include <sys/avl.h> 40 #include <sys/list.h> 41 42 #ifdef __cplusplus 43 extern "C" { 44 #endif 45 46 /* 47 * kernel memory allocator: implementation-private data structures 48 * 49 * Lock order: 50 * 1. cache_lock 51 * 2. cc_lock in order by CPU ID 52 * 3. cache_depot_lock 53 * 54 * Do not call kmem_cache_alloc() or taskq_dispatch() while holding any of the 55 * above locks. 56 */ 57 58 #define KMF_AUDIT 0x00000001 /* transaction auditing */ 59 #define KMF_DEADBEEF 0x00000002 /* deadbeef checking */ 60 #define KMF_REDZONE 0x00000004 /* redzone checking */ 61 #define KMF_CONTENTS 0x00000008 /* freed-buffer content logging */ 62 #define KMF_STICKY 0x00000010 /* if set, override /etc/system */ 63 #define KMF_NOMAGAZINE 0x00000020 /* disable per-cpu magazines */ 64 #define KMF_FIREWALL 0x00000040 /* put all bufs before unmapped pages */ 65 #define KMF_LITE 0x00000100 /* lightweight debugging */ 66 67 #define KMF_HASH 0x00000200 /* cache has hash table */ 68 #define KMF_RANDOMIZE 0x00000400 /* randomize other kmem_flags */ 69 70 #define KMF_DUMPDIVERT 0x00001000 /* use alternate memory at dump time */ 71 #define KMF_DUMPUNSAFE 0x00002000 /* flag caches used at dump time */ 72 #define KMF_PREFILL 0x00004000 /* Prefill the slab when created. */ 73 74 #define KMF_BUFTAG (KMF_DEADBEEF | KMF_REDZONE) 75 #define KMF_TOUCH (KMF_BUFTAG | KMF_LITE | KMF_CONTENTS) 76 #define KMF_RANDOM (KMF_TOUCH | KMF_AUDIT | KMF_NOMAGAZINE) 77 #define KMF_DEBUG (KMF_RANDOM | KMF_FIREWALL) 78 79 #define KMEM_STACK_DEPTH 15 80 81 #define KMEM_FREE_PATTERN 0xdeadbeefdeadbeefULL 82 #define KMEM_UNINITIALIZED_PATTERN 0xbaddcafebaddcafeULL 83 #define KMEM_REDZONE_PATTERN 0xfeedfacefeedfaceULL 84 #define KMEM_REDZONE_BYTE 0xbb 85 86 /* 87 * Redzone size encodings for kmem_alloc() / kmem_free(). We encode the 88 * allocation size, rather than storing it directly, so that kmem_free() 89 * can distinguish frees of the wrong size from redzone violations. 90 * 91 * A size of zero is never valid. 92 */ 93 #define KMEM_SIZE_ENCODE(x) (251 * (x) + 1) 94 #define KMEM_SIZE_DECODE(x) ((x) / 251) 95 #define KMEM_SIZE_VALID(x) ((x) % 251 == 1 && (x) != 1) 96 97 98 #define KMEM_ALIGN 8 /* min guaranteed alignment */ 99 #define KMEM_ALIGN_SHIFT 3 /* log2(KMEM_ALIGN) */ 100 #define KMEM_VOID_FRACTION 8 /* never waste more than 1/8 of slab */ 101 102 #define KMEM_SLAB_IS_PARTIAL(sp) \ 103 ((sp)->slab_refcnt > 0 && (sp)->slab_refcnt < (sp)->slab_chunks) 104 #define KMEM_SLAB_IS_ALL_USED(sp) \ 105 ((sp)->slab_refcnt == (sp)->slab_chunks) 106 107 /* 108 * The bufctl (buffer control) structure keeps some minimal information 109 * about each buffer: its address, its slab, and its current linkage, 110 * which is either on the slab's freelist (if the buffer is free), or 111 * on the cache's buf-to-bufctl hash table (if the buffer is allocated). 112 * In the case of non-hashed, or "raw", caches (the common case), only 113 * the freelist linkage is necessary: the buffer address is at a fixed 114 * offset from the bufctl address, and the slab is at the end of the page. 115 * 116 * NOTE: bc_next must be the first field; raw buffers have linkage only. 117 */ 118 typedef struct kmem_bufctl { 119 struct kmem_bufctl *bc_next; /* next bufctl struct */ 120 void *bc_addr; /* address of buffer */ 121 struct kmem_slab *bc_slab; /* controlling slab */ 122 } kmem_bufctl_t; 123 124 /* 125 * The KMF_AUDIT version of the bufctl structure. The beginning of this 126 * structure must be identical to the normal bufctl structure so that 127 * pointers are interchangeable. 128 */ 129 typedef struct kmem_bufctl_audit { 130 struct kmem_bufctl *bc_next; /* next bufctl struct */ 131 void *bc_addr; /* address of buffer */ 132 struct kmem_slab *bc_slab; /* controlling slab */ 133 kmem_cache_t *bc_cache; /* controlling cache */ 134 hrtime_t bc_timestamp; /* transaction time */ 135 kthread_t *bc_thread; /* thread doing transaction */ 136 struct kmem_bufctl *bc_lastlog; /* last log entry */ 137 void *bc_contents; /* contents at last free */ 138 int bc_depth; /* stack depth */ 139 pc_t bc_stack[KMEM_STACK_DEPTH]; /* pc stack */ 140 } kmem_bufctl_audit_t; 141 142 /* 143 * A kmem_buftag structure is appended to each buffer whenever any of the 144 * KMF_BUFTAG flags (KMF_DEADBEEF, KMF_REDZONE, KMF_VERIFY) are set. 145 */ 146 typedef struct kmem_buftag { 147 uint64_t bt_redzone; /* 64-bit redzone pattern */ 148 kmem_bufctl_t *bt_bufctl; /* bufctl */ 149 intptr_t bt_bxstat; /* bufctl ^ (alloc/free) */ 150 } kmem_buftag_t; 151 152 /* 153 * A variant of the kmem_buftag structure used for KMF_LITE caches. 154 * Previous callers are stored in reverse chronological order. (i.e. most 155 * recent first) 156 */ 157 typedef struct kmem_buftag_lite { 158 kmem_buftag_t bt_buftag; /* a normal buftag */ 159 pc_t bt_history[1]; /* zero or more callers */ 160 } kmem_buftag_lite_t; 161 162 #define KMEM_BUFTAG_LITE_SIZE(f) \ 163 (offsetof(kmem_buftag_lite_t, bt_history[f])) 164 165 #define KMEM_BUFTAG(cp, buf) \ 166 ((kmem_buftag_t *)((char *)(buf) + (cp)->cache_buftag)) 167 168 #define KMEM_BUFCTL(cp, buf) \ 169 ((kmem_bufctl_t *)((char *)(buf) + (cp)->cache_bufctl)) 170 171 #define KMEM_BUF(cp, bcp) \ 172 ((void *)((char *)(bcp) - (cp)->cache_bufctl)) 173 174 #define KMEM_SLAB(cp, buf) \ 175 ((kmem_slab_t *)P2END((uintptr_t)(buf), (cp)->cache_slabsize) - 1) 176 177 /* 178 * Test for using alternate memory at dump time. 179 */ 180 #define KMEM_DUMP(cp) ((cp)->cache_flags & KMF_DUMPDIVERT) 181 #define KMEM_DUMPCC(ccp) ((ccp)->cc_flags & KMF_DUMPDIVERT) 182 183 /* 184 * The "CPU" macro loads a cpu_t that refers to the cpu that the current 185 * thread is running on at the time the macro is executed. A context switch 186 * may occur immediately after loading this data structure, leaving this 187 * thread pointing at the cpu_t for the previous cpu. This is not a problem; 188 * we'd just end up checking the previous cpu's per-cpu cache, and then check 189 * the other layers of the kmem cache if need be. 190 * 191 * It's not even a problem if the old cpu gets DR'ed out during the context 192 * switch. The cpu-remove DR operation bzero()s the cpu_t, but doesn't free 193 * it. So the cpu_t's cpu_cache_offset would read as 0, causing us to use 194 * cpu 0's per-cpu cache. 195 * 196 * So, there is no need to disable kernel preemption while using the CPU macro 197 * below since if we have been context switched, there will not be any 198 * correctness problem, just a momentary use of a different per-cpu cache. 199 */ 200 201 #define KMEM_CPU_CACHE(cp) \ 202 ((kmem_cpu_cache_t *)((char *)(&cp->cache_cpu) + CPU->cpu_cache_offset)) 203 204 #define KMEM_MAGAZINE_VALID(cp, mp) \ 205 (((kmem_slab_t *)P2END((uintptr_t)(mp), PAGESIZE) - 1)->slab_cache == \ 206 (cp)->cache_magtype->mt_cache) 207 208 #define KMEM_SLAB_OFFSET(sp, buf) \ 209 ((size_t)((uintptr_t)(buf) - (uintptr_t)((sp)->slab_base))) 210 211 #define KMEM_SLAB_MEMBER(sp, buf) \ 212 (KMEM_SLAB_OFFSET(sp, buf) < (sp)->slab_cache->cache_slabsize) 213 214 #define KMEM_BUFTAG_ALLOC 0xa110c8edUL 215 #define KMEM_BUFTAG_FREE 0xf4eef4eeUL 216 217 /* slab_later_count thresholds */ 218 #define KMEM_DISBELIEF 3 219 220 /* slab_flags */ 221 #define KMEM_SLAB_NOMOVE 0x1 222 #define KMEM_SLAB_MOVE_PENDING 0x2 223 224 typedef struct kmem_slab { 225 struct kmem_cache *slab_cache; /* controlling cache */ 226 void *slab_base; /* base of allocated memory */ 227 avl_node_t slab_link; /* slab linkage */ 228 struct kmem_bufctl *slab_head; /* first free buffer */ 229 long slab_refcnt; /* outstanding allocations */ 230 long slab_chunks; /* chunks (bufs) in this slab */ 231 uint32_t slab_stuck_offset; /* unmoved buffer offset */ 232 uint16_t slab_later_count; /* cf KMEM_CBRC_LATER */ 233 uint16_t slab_flags; /* bits to mark the slab */ 234 } kmem_slab_t; 235 236 #define KMEM_HASH_INITIAL 64 237 238 #define KMEM_HASH(cp, buf) \ 239 ((cp)->cache_hash_table + \ 240 (((uintptr_t)(buf) >> (cp)->cache_hash_shift) & (cp)->cache_hash_mask)) 241 242 typedef struct kmem_magazine { 243 void *mag_next; 244 void *mag_round[1]; /* one or more rounds */ 245 } kmem_magazine_t; 246 247 /* 248 * The magazine types for fast per-cpu allocation 249 */ 250 typedef struct kmem_magtype { 251 short mt_magsize; /* magazine size (number of rounds) */ 252 int mt_align; /* magazine alignment */ 253 size_t mt_minbuf; /* all smaller buffers qualify */ 254 size_t mt_maxbuf; /* no larger buffers qualify */ 255 kmem_cache_t *mt_cache; /* magazine cache */ 256 } kmem_magtype_t; 257 258 #define KMEM_CPU_CACHE_SIZE 64 /* must be power of 2 */ 259 #define KMEM_CPU_PAD (KMEM_CPU_CACHE_SIZE - sizeof (kmutex_t) - \ 260 2 * sizeof (uint64_t) - 2 * sizeof (void *) - sizeof (int) - \ 261 5 * sizeof (short)) 262 #define KMEM_CACHE_SIZE(ncpus) \ 263 ((size_t)(&((kmem_cache_t *)0)->cache_cpu[ncpus])) 264 265 /* Offset from kmem_cache->cache_cpu for per cpu caches */ 266 #define KMEM_CPU_CACHE_OFFSET(cpuid) \ 267 ((size_t)(&((kmem_cache_t *)0)->cache_cpu[cpuid]) - \ 268 (size_t)(&((kmem_cache_t *)0)->cache_cpu)) 269 270 typedef struct kmem_cpu_cache { 271 kmutex_t cc_lock; /* protects this cpu's local cache */ 272 uint64_t cc_alloc; /* allocations from this cpu */ 273 uint64_t cc_free; /* frees to this cpu */ 274 kmem_magazine_t *cc_loaded; /* the currently loaded magazine */ 275 kmem_magazine_t *cc_ploaded; /* the previously loaded magazine */ 276 int cc_flags; /* CPU-local copy of cache_flags */ 277 short cc_rounds; /* number of objects in loaded mag */ 278 short cc_prounds; /* number of objects in previous mag */ 279 short cc_magsize; /* number of rounds in a full mag */ 280 short cc_dump_rounds; /* dump time copy of cc_rounds */ 281 short cc_dump_prounds; /* dump time copy of cc_prounds */ 282 char cc_pad[KMEM_CPU_PAD]; /* for nice alignment */ 283 } kmem_cpu_cache_t; 284 285 /* 286 * The magazine lists used in the depot. 287 */ 288 typedef struct kmem_maglist { 289 kmem_magazine_t *ml_list; /* magazine list */ 290 long ml_total; /* number of magazines */ 291 long ml_min; /* min since last update */ 292 long ml_reaplimit; /* max reapable magazines */ 293 uint64_t ml_alloc; /* allocations from this list */ 294 } kmem_maglist_t; 295 296 typedef struct kmem_defrag { 297 /* 298 * Statistics 299 */ 300 uint64_t kmd_callbacks; /* move callbacks */ 301 uint64_t kmd_yes; /* KMEM_CBRC_YES responses */ 302 uint64_t kmd_no; /* NO responses */ 303 uint64_t kmd_later; /* LATER responses */ 304 uint64_t kmd_dont_need; /* DONT_NEED responses */ 305 uint64_t kmd_dont_know; /* DONT_KNOW responses */ 306 uint64_t kmd_slabs_freed; /* slabs freed by moves */ 307 uint64_t kmd_defrags; /* kmem_cache_defrag() */ 308 uint64_t kmd_scans; /* kmem_cache_scan() */ 309 310 /* 311 * Consolidator fields 312 */ 313 avl_tree_t kmd_moves_pending; /* buffer moves pending */ 314 list_t kmd_deadlist; /* deferred slab frees */ 315 size_t kmd_deadcount; /* # of slabs in kmd_deadlist */ 316 uint8_t kmd_reclaim_numer; /* slab usage threshold */ 317 uint8_t kmd_pad1; /* compiler padding */ 318 uint16_t kmd_consolidate; /* triggers consolidator */ 319 uint32_t kmd_pad2; /* compiler padding */ 320 size_t kmd_slabs_sought; /* reclaimable slabs sought */ 321 size_t kmd_slabs_found; /* reclaimable slabs found */ 322 size_t kmd_tries; /* nth scan interval counter */ 323 /* 324 * Fields used to ASSERT that the client does not kmem_cache_free() 325 * objects passed to the move callback. 326 */ 327 void *kmd_from_buf; /* object to move */ 328 void *kmd_to_buf; /* move destination */ 329 kthread_t *kmd_thread; /* thread calling move */ 330 } kmem_defrag_t; 331 332 typedef struct kmem_dump { 333 void *kd_freelist; /* heap during crash dump */ 334 uint_t kd_alloc_fails; /* # of allocation failures */ 335 uint_t kd_unsafe; /* cache was used, but unsafe */ 336 } kmem_dump_t; 337 338 #define KMEM_CACHE_NAMELEN 31 339 340 struct kmem_cache { 341 /* 342 * Statistics 343 */ 344 uint64_t cache_slab_create; /* slab creates */ 345 uint64_t cache_slab_destroy; /* slab destroys */ 346 uint64_t cache_slab_alloc; /* slab layer allocations */ 347 uint64_t cache_slab_free; /* slab layer frees */ 348 uint64_t cache_alloc_fail; /* total failed allocations */ 349 uint64_t cache_buftotal; /* total buffers */ 350 uint64_t cache_bufmax; /* max buffers ever */ 351 uint64_t cache_bufslab; /* buffers free in slab layer */ 352 uint64_t cache_reap; /* cache reaps */ 353 uint64_t cache_rescale; /* hash table rescales */ 354 uint64_t cache_lookup_depth; /* hash lookup depth */ 355 uint64_t cache_depot_contention; /* mutex contention count */ 356 uint64_t cache_depot_contention_prev; /* previous snapshot */ 357 358 /* 359 * Cache properties 360 */ 361 char cache_name[KMEM_CACHE_NAMELEN + 1]; 362 size_t cache_bufsize; /* object size */ 363 size_t cache_align; /* object alignment */ 364 int (*cache_constructor)(void *, void *, int); 365 void (*cache_destructor)(void *, void *); 366 void (*cache_reclaim)(void *); 367 kmem_cbrc_t (*cache_move)(void *, void *, size_t, void *); 368 void *cache_private; /* opaque arg to callbacks */ 369 vmem_t *cache_arena; /* vmem source for slabs */ 370 int cache_cflags; /* cache creation flags */ 371 int cache_flags; /* various cache state info */ 372 uint32_t cache_mtbf; /* induced alloc failure rate */ 373 uint32_t cache_pad1; /* compiler padding */ 374 kstat_t *cache_kstat; /* exported statistics */ 375 list_node_t cache_link; /* cache linkage */ 376 377 /* 378 * Slab layer 379 */ 380 kmutex_t cache_lock; /* protects slab layer */ 381 size_t cache_chunksize; /* buf + alignment [+ debug] */ 382 size_t cache_slabsize; /* size of a slab */ 383 size_t cache_maxchunks; /* max buffers per slab */ 384 size_t cache_bufctl; /* buf-to-bufctl distance */ 385 size_t cache_buftag; /* buf-to-buftag distance */ 386 size_t cache_verify; /* bytes to verify */ 387 size_t cache_contents; /* bytes of saved content */ 388 size_t cache_color; /* next slab color */ 389 size_t cache_mincolor; /* maximum slab color */ 390 size_t cache_maxcolor; /* maximum slab color */ 391 size_t cache_hash_shift; /* get to interesting bits */ 392 size_t cache_hash_mask; /* hash table mask */ 393 list_t cache_complete_slabs; /* completely allocated slabs */ 394 size_t cache_complete_slab_count; 395 avl_tree_t cache_partial_slabs; /* partial slab freelist */ 396 size_t cache_partial_binshift; /* for AVL sort bins */ 397 kmem_cache_t *cache_bufctl_cache; /* source of bufctls */ 398 kmem_bufctl_t **cache_hash_table; /* hash table base */ 399 kmem_defrag_t *cache_defrag; /* slab consolidator fields */ 400 401 /* 402 * Depot layer 403 */ 404 kmutex_t cache_depot_lock; /* protects depot */ 405 kmem_magtype_t *cache_magtype; /* magazine type */ 406 kmem_maglist_t cache_full; /* full magazines */ 407 kmem_maglist_t cache_empty; /* empty magazines */ 408 kmem_dump_t cache_dump; /* used during crash dump */ 409 410 /* 411 * Per-CPU layer 412 */ 413 kmem_cpu_cache_t cache_cpu[1]; /* max_ncpus actual elements */ 414 }; 415 416 typedef struct kmem_cpu_log_header { 417 kmutex_t clh_lock; 418 char *clh_current; 419 size_t clh_avail; 420 int clh_chunk; 421 int clh_hits; 422 char clh_pad[64 - sizeof (kmutex_t) - sizeof (char *) - 423 sizeof (size_t) - 2 * sizeof (int)]; 424 } kmem_cpu_log_header_t; 425 426 typedef struct kmem_log_header { 427 kmutex_t lh_lock; 428 char *lh_base; 429 int *lh_free; 430 size_t lh_chunksize; 431 int lh_nchunks; 432 int lh_head; 433 int lh_tail; 434 int lh_hits; 435 kmem_cpu_log_header_t lh_cpu[1]; /* ncpus actually allocated */ 436 } kmem_log_header_t; 437 438 /* kmem_move kmm_flags */ 439 #define KMM_DESPERATE 0x1 440 #define KMM_NOTIFY 0x2 441 #define KMM_DEBUG 0x4 442 443 typedef struct kmem_move { 444 kmem_slab_t *kmm_from_slab; 445 void *kmm_from_buf; 446 void *kmm_to_buf; 447 avl_node_t kmm_entry; 448 int kmm_flags; 449 } kmem_move_t; 450 451 /* 452 * In order to consolidate partial slabs, it must be possible for the cache to 453 * have partial slabs. 454 */ 455 #define KMEM_IS_MOVABLE(cp) \ 456 (((cp)->cache_chunksize * 2) <= (cp)->cache_slabsize) 457 458 #ifdef __cplusplus 459 } 460 #endif 461 462 #endif /* _SYS_KMEM_IMPL_H */ 463