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