1 /* Internal definitions for FS-Cache 2 * 3 * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 /* 13 * Lock order, in the order in which multiple locks should be obtained: 14 * - fscache_addremove_sem 15 * - cookie->lock 16 * - cookie->parent->lock 17 * - cache->object_list_lock 18 * - object->lock 19 * - object->parent->lock 20 * - cookie->stores_lock 21 * - fscache_thread_lock 22 * 23 */ 24 25 #ifdef pr_fmt 26 #undef pr_fmt 27 #endif 28 29 #define pr_fmt(fmt) "FS-Cache: " fmt 30 31 #include <linux/fscache-cache.h> 32 #include <trace/events/fscache.h> 33 #include <linux/sched.h> 34 #include <linux/seq_file.h> 35 36 #define FSCACHE_MIN_THREADS 4 37 #define FSCACHE_MAX_THREADS 32 38 39 /* 40 * cache.c 41 */ 42 extern struct list_head fscache_cache_list; 43 extern struct rw_semaphore fscache_addremove_sem; 44 45 extern struct fscache_cache *fscache_select_cache_for_object( 46 struct fscache_cookie *); 47 48 /* 49 * cookie.c 50 */ 51 extern struct kmem_cache *fscache_cookie_jar; 52 53 extern void fscache_free_cookie(struct fscache_cookie *); 54 extern struct fscache_cookie *fscache_alloc_cookie(struct fscache_cookie *, 55 const struct fscache_cookie_def *, 56 const void *, size_t, 57 const void *, size_t, 58 void *, loff_t); 59 extern struct fscache_cookie *fscache_hash_cookie(struct fscache_cookie *); 60 extern void fscache_cookie_put(struct fscache_cookie *, 61 enum fscache_cookie_trace); 62 63 /* 64 * fsdef.c 65 */ 66 extern struct fscache_cookie fscache_fsdef_index; 67 extern struct fscache_cookie_def fscache_fsdef_netfs_def; 68 69 /* 70 * histogram.c 71 */ 72 #ifdef CONFIG_FSCACHE_HISTOGRAM 73 extern atomic_t fscache_obj_instantiate_histogram[HZ]; 74 extern atomic_t fscache_objs_histogram[HZ]; 75 extern atomic_t fscache_ops_histogram[HZ]; 76 extern atomic_t fscache_retrieval_delay_histogram[HZ]; 77 extern atomic_t fscache_retrieval_histogram[HZ]; 78 79 static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif) 80 { 81 unsigned long jif = jiffies - start_jif; 82 if (jif >= HZ) 83 jif = HZ - 1; 84 atomic_inc(&histogram[jif]); 85 } 86 87 extern const struct seq_operations fscache_histogram_ops; 88 89 #else 90 #define fscache_hist(hist, start_jif) do {} while (0) 91 #endif 92 93 /* 94 * main.c 95 */ 96 extern unsigned fscache_defer_lookup; 97 extern unsigned fscache_defer_create; 98 extern unsigned fscache_debug; 99 extern struct kobject *fscache_root; 100 extern struct workqueue_struct *fscache_object_wq; 101 extern struct workqueue_struct *fscache_op_wq; 102 DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait); 103 104 static inline bool fscache_object_congested(void) 105 { 106 return workqueue_congested(WORK_CPU_UNBOUND, fscache_object_wq); 107 } 108 109 /* 110 * object.c 111 */ 112 extern void fscache_enqueue_object(struct fscache_object *); 113 114 /* 115 * object-list.c 116 */ 117 #ifdef CONFIG_FSCACHE_OBJECT_LIST 118 extern const struct file_operations fscache_objlist_fops; 119 120 extern void fscache_objlist_add(struct fscache_object *); 121 extern void fscache_objlist_remove(struct fscache_object *); 122 #else 123 #define fscache_objlist_add(object) do {} while(0) 124 #define fscache_objlist_remove(object) do {} while(0) 125 #endif 126 127 /* 128 * operation.c 129 */ 130 extern int fscache_submit_exclusive_op(struct fscache_object *, 131 struct fscache_operation *); 132 extern int fscache_submit_op(struct fscache_object *, 133 struct fscache_operation *); 134 extern int fscache_cancel_op(struct fscache_operation *, bool); 135 extern void fscache_cancel_all_ops(struct fscache_object *); 136 extern void fscache_abort_object(struct fscache_object *); 137 extern void fscache_start_operations(struct fscache_object *); 138 extern void fscache_operation_gc(struct work_struct *); 139 140 /* 141 * page.c 142 */ 143 extern int fscache_wait_for_deferred_lookup(struct fscache_cookie *); 144 extern int fscache_wait_for_operation_activation(struct fscache_object *, 145 struct fscache_operation *, 146 atomic_t *, 147 atomic_t *); 148 extern void fscache_invalidate_writes(struct fscache_cookie *); 149 150 /* 151 * proc.c 152 */ 153 #ifdef CONFIG_PROC_FS 154 extern int __init fscache_proc_init(void); 155 extern void fscache_proc_cleanup(void); 156 #else 157 #define fscache_proc_init() (0) 158 #define fscache_proc_cleanup() do {} while (0) 159 #endif 160 161 /* 162 * stats.c 163 */ 164 #ifdef CONFIG_FSCACHE_STATS 165 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS]; 166 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS]; 167 168 extern atomic_t fscache_n_op_pend; 169 extern atomic_t fscache_n_op_run; 170 extern atomic_t fscache_n_op_enqueue; 171 extern atomic_t fscache_n_op_deferred_release; 172 extern atomic_t fscache_n_op_initialised; 173 extern atomic_t fscache_n_op_release; 174 extern atomic_t fscache_n_op_gc; 175 extern atomic_t fscache_n_op_cancelled; 176 extern atomic_t fscache_n_op_rejected; 177 178 extern atomic_t fscache_n_attr_changed; 179 extern atomic_t fscache_n_attr_changed_ok; 180 extern atomic_t fscache_n_attr_changed_nobufs; 181 extern atomic_t fscache_n_attr_changed_nomem; 182 extern atomic_t fscache_n_attr_changed_calls; 183 184 extern atomic_t fscache_n_allocs; 185 extern atomic_t fscache_n_allocs_ok; 186 extern atomic_t fscache_n_allocs_wait; 187 extern atomic_t fscache_n_allocs_nobufs; 188 extern atomic_t fscache_n_allocs_intr; 189 extern atomic_t fscache_n_allocs_object_dead; 190 extern atomic_t fscache_n_alloc_ops; 191 extern atomic_t fscache_n_alloc_op_waits; 192 193 extern atomic_t fscache_n_retrievals; 194 extern atomic_t fscache_n_retrievals_ok; 195 extern atomic_t fscache_n_retrievals_wait; 196 extern atomic_t fscache_n_retrievals_nodata; 197 extern atomic_t fscache_n_retrievals_nobufs; 198 extern atomic_t fscache_n_retrievals_intr; 199 extern atomic_t fscache_n_retrievals_nomem; 200 extern atomic_t fscache_n_retrievals_object_dead; 201 extern atomic_t fscache_n_retrieval_ops; 202 extern atomic_t fscache_n_retrieval_op_waits; 203 204 extern atomic_t fscache_n_stores; 205 extern atomic_t fscache_n_stores_ok; 206 extern atomic_t fscache_n_stores_again; 207 extern atomic_t fscache_n_stores_nobufs; 208 extern atomic_t fscache_n_stores_oom; 209 extern atomic_t fscache_n_store_ops; 210 extern atomic_t fscache_n_store_calls; 211 extern atomic_t fscache_n_store_pages; 212 extern atomic_t fscache_n_store_radix_deletes; 213 extern atomic_t fscache_n_store_pages_over_limit; 214 215 extern atomic_t fscache_n_store_vmscan_not_storing; 216 extern atomic_t fscache_n_store_vmscan_gone; 217 extern atomic_t fscache_n_store_vmscan_busy; 218 extern atomic_t fscache_n_store_vmscan_cancelled; 219 extern atomic_t fscache_n_store_vmscan_wait; 220 221 extern atomic_t fscache_n_marks; 222 extern atomic_t fscache_n_uncaches; 223 224 extern atomic_t fscache_n_acquires; 225 extern atomic_t fscache_n_acquires_null; 226 extern atomic_t fscache_n_acquires_no_cache; 227 extern atomic_t fscache_n_acquires_ok; 228 extern atomic_t fscache_n_acquires_nobufs; 229 extern atomic_t fscache_n_acquires_oom; 230 231 extern atomic_t fscache_n_invalidates; 232 extern atomic_t fscache_n_invalidates_run; 233 234 extern atomic_t fscache_n_updates; 235 extern atomic_t fscache_n_updates_null; 236 extern atomic_t fscache_n_updates_run; 237 238 extern atomic_t fscache_n_relinquishes; 239 extern atomic_t fscache_n_relinquishes_null; 240 extern atomic_t fscache_n_relinquishes_waitcrt; 241 extern atomic_t fscache_n_relinquishes_retire; 242 243 extern atomic_t fscache_n_cookie_index; 244 extern atomic_t fscache_n_cookie_data; 245 extern atomic_t fscache_n_cookie_special; 246 247 extern atomic_t fscache_n_object_alloc; 248 extern atomic_t fscache_n_object_no_alloc; 249 extern atomic_t fscache_n_object_lookups; 250 extern atomic_t fscache_n_object_lookups_negative; 251 extern atomic_t fscache_n_object_lookups_positive; 252 extern atomic_t fscache_n_object_lookups_timed_out; 253 extern atomic_t fscache_n_object_created; 254 extern atomic_t fscache_n_object_avail; 255 extern atomic_t fscache_n_object_dead; 256 257 extern atomic_t fscache_n_checkaux_none; 258 extern atomic_t fscache_n_checkaux_okay; 259 extern atomic_t fscache_n_checkaux_update; 260 extern atomic_t fscache_n_checkaux_obsolete; 261 262 extern atomic_t fscache_n_cop_alloc_object; 263 extern atomic_t fscache_n_cop_lookup_object; 264 extern atomic_t fscache_n_cop_lookup_complete; 265 extern atomic_t fscache_n_cop_grab_object; 266 extern atomic_t fscache_n_cop_invalidate_object; 267 extern atomic_t fscache_n_cop_update_object; 268 extern atomic_t fscache_n_cop_drop_object; 269 extern atomic_t fscache_n_cop_put_object; 270 extern atomic_t fscache_n_cop_sync_cache; 271 extern atomic_t fscache_n_cop_attr_changed; 272 extern atomic_t fscache_n_cop_read_or_alloc_page; 273 extern atomic_t fscache_n_cop_read_or_alloc_pages; 274 extern atomic_t fscache_n_cop_allocate_page; 275 extern atomic_t fscache_n_cop_allocate_pages; 276 extern atomic_t fscache_n_cop_write_page; 277 extern atomic_t fscache_n_cop_uncache_page; 278 extern atomic_t fscache_n_cop_dissociate_pages; 279 280 extern atomic_t fscache_n_cache_no_space_reject; 281 extern atomic_t fscache_n_cache_stale_objects; 282 extern atomic_t fscache_n_cache_retired_objects; 283 extern atomic_t fscache_n_cache_culled_objects; 284 285 static inline void fscache_stat(atomic_t *stat) 286 { 287 atomic_inc(stat); 288 } 289 290 static inline void fscache_stat_d(atomic_t *stat) 291 { 292 atomic_dec(stat); 293 } 294 295 #define __fscache_stat(stat) (stat) 296 297 int fscache_stats_show(struct seq_file *m, void *v); 298 #else 299 300 #define __fscache_stat(stat) (NULL) 301 #define fscache_stat(stat) do {} while (0) 302 #define fscache_stat_d(stat) do {} while (0) 303 #endif 304 305 /* 306 * raise an event on an object 307 * - if the event is not masked for that object, then the object is 308 * queued for attention by the thread pool. 309 */ 310 static inline void fscache_raise_event(struct fscache_object *object, 311 unsigned event) 312 { 313 BUG_ON(event >= NR_FSCACHE_OBJECT_EVENTS); 314 #if 0 315 printk("*** fscache_raise_event(OBJ%d{%lx},%x)\n", 316 object->debug_id, object->event_mask, (1 << event)); 317 #endif 318 if (!test_and_set_bit(event, &object->events) && 319 test_bit(event, &object->event_mask)) 320 fscache_enqueue_object(object); 321 } 322 323 static inline void fscache_cookie_get(struct fscache_cookie *cookie, 324 enum fscache_cookie_trace where) 325 { 326 int usage = atomic_inc_return(&cookie->usage); 327 328 trace_fscache_cookie(cookie, where, usage); 329 } 330 331 /* 332 * get an extra reference to a netfs retrieval context 333 */ 334 static inline 335 void *fscache_get_context(struct fscache_cookie *cookie, void *context) 336 { 337 if (cookie->def->get_context) 338 cookie->def->get_context(cookie->netfs_data, context); 339 return context; 340 } 341 342 /* 343 * release a reference to a netfs retrieval context 344 */ 345 static inline 346 void fscache_put_context(struct fscache_cookie *cookie, void *context) 347 { 348 if (cookie->def->put_context) 349 cookie->def->put_context(cookie->netfs_data, context); 350 } 351 352 /* 353 * Update the auxiliary data on a cookie. 354 */ 355 static inline 356 void fscache_update_aux(struct fscache_cookie *cookie, const void *aux_data) 357 { 358 void *p; 359 360 if (!aux_data) 361 return; 362 if (cookie->aux_len <= sizeof(cookie->inline_aux)) 363 p = cookie->inline_aux; 364 else 365 p = cookie->aux; 366 367 if (memcmp(p, aux_data, cookie->aux_len) != 0) { 368 memcpy(p, aux_data, cookie->aux_len); 369 set_bit(FSCACHE_COOKIE_AUX_UPDATED, &cookie->flags); 370 } 371 } 372 373 /*****************************************************************************/ 374 /* 375 * debug tracing 376 */ 377 #define dbgprintk(FMT, ...) \ 378 printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__) 379 380 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 381 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 382 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__) 383 384 #define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__) 385 386 #ifdef __KDEBUG 387 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__) 388 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__) 389 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__) 390 391 #elif defined(CONFIG_FSCACHE_DEBUG) 392 #define _enter(FMT, ...) \ 393 do { \ 394 if (__do_kdebug(ENTER)) \ 395 kenter(FMT, ##__VA_ARGS__); \ 396 } while (0) 397 398 #define _leave(FMT, ...) \ 399 do { \ 400 if (__do_kdebug(LEAVE)) \ 401 kleave(FMT, ##__VA_ARGS__); \ 402 } while (0) 403 404 #define _debug(FMT, ...) \ 405 do { \ 406 if (__do_kdebug(DEBUG)) \ 407 kdebug(FMT, ##__VA_ARGS__); \ 408 } while (0) 409 410 #else 411 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__) 412 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 413 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__) 414 #endif 415 416 /* 417 * determine whether a particular optional debugging point should be logged 418 * - we need to go through three steps to persuade cpp to correctly join the 419 * shorthand in FSCACHE_DEBUG_LEVEL with its prefix 420 */ 421 #define ____do_kdebug(LEVEL, POINT) \ 422 unlikely((fscache_debug & \ 423 (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3)))) 424 #define ___do_kdebug(LEVEL, POINT) \ 425 ____do_kdebug(LEVEL, POINT) 426 #define __do_kdebug(POINT) \ 427 ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT) 428 429 #define FSCACHE_DEBUG_CACHE 0 430 #define FSCACHE_DEBUG_COOKIE 1 431 #define FSCACHE_DEBUG_PAGE 2 432 #define FSCACHE_DEBUG_OPERATION 3 433 434 #define FSCACHE_POINT_ENTER 1 435 #define FSCACHE_POINT_LEAVE 2 436 #define FSCACHE_POINT_DEBUG 4 437 438 #ifndef FSCACHE_DEBUG_LEVEL 439 #define FSCACHE_DEBUG_LEVEL CACHE 440 #endif 441 442 /* 443 * assertions 444 */ 445 #if 1 /* defined(__KDEBUGALL) */ 446 447 #define ASSERT(X) \ 448 do { \ 449 if (unlikely(!(X))) { \ 450 pr_err("\n"); \ 451 pr_err("Assertion failed\n"); \ 452 BUG(); \ 453 } \ 454 } while (0) 455 456 #define ASSERTCMP(X, OP, Y) \ 457 do { \ 458 if (unlikely(!((X) OP (Y)))) { \ 459 pr_err("\n"); \ 460 pr_err("Assertion failed\n"); \ 461 pr_err("%lx " #OP " %lx is false\n", \ 462 (unsigned long)(X), (unsigned long)(Y)); \ 463 BUG(); \ 464 } \ 465 } while (0) 466 467 #define ASSERTIF(C, X) \ 468 do { \ 469 if (unlikely((C) && !(X))) { \ 470 pr_err("\n"); \ 471 pr_err("Assertion failed\n"); \ 472 BUG(); \ 473 } \ 474 } while (0) 475 476 #define ASSERTIFCMP(C, X, OP, Y) \ 477 do { \ 478 if (unlikely((C) && !((X) OP (Y)))) { \ 479 pr_err("\n"); \ 480 pr_err("Assertion failed\n"); \ 481 pr_err("%lx " #OP " %lx is false\n", \ 482 (unsigned long)(X), (unsigned long)(Y)); \ 483 BUG(); \ 484 } \ 485 } while (0) 486 487 #else 488 489 #define ASSERT(X) do {} while (0) 490 #define ASSERTCMP(X, OP, Y) do {} while (0) 491 #define ASSERTIF(C, X) do {} while (0) 492 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0) 493 494 #endif /* assert or not */ 495