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