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 #include <linux/fscache-cache.h> 26 #include <linux/sched.h> 27 28 #define FSCACHE_MIN_THREADS 4 29 #define FSCACHE_MAX_THREADS 32 30 31 /* 32 * cache.c 33 */ 34 extern struct list_head fscache_cache_list; 35 extern struct rw_semaphore fscache_addremove_sem; 36 37 extern struct fscache_cache *fscache_select_cache_for_object( 38 struct fscache_cookie *); 39 40 /* 41 * cookie.c 42 */ 43 extern struct kmem_cache *fscache_cookie_jar; 44 45 extern void fscache_cookie_init_once(void *); 46 extern void __fscache_cookie_put(struct fscache_cookie *); 47 48 /* 49 * fsdef.c 50 */ 51 extern struct fscache_cookie fscache_fsdef_index; 52 extern struct fscache_cookie_def fscache_fsdef_netfs_def; 53 54 /* 55 * histogram.c 56 */ 57 #ifdef CONFIG_FSCACHE_HISTOGRAM 58 extern atomic_t fscache_obj_instantiate_histogram[HZ]; 59 extern atomic_t fscache_objs_histogram[HZ]; 60 extern atomic_t fscache_ops_histogram[HZ]; 61 extern atomic_t fscache_retrieval_delay_histogram[HZ]; 62 extern atomic_t fscache_retrieval_histogram[HZ]; 63 64 static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif) 65 { 66 unsigned long jif = jiffies - start_jif; 67 if (jif >= HZ) 68 jif = HZ - 1; 69 atomic_inc(&histogram[jif]); 70 } 71 72 extern const struct file_operations fscache_histogram_fops; 73 74 #else 75 #define fscache_hist(hist, start_jif) do {} while (0) 76 #endif 77 78 /* 79 * main.c 80 */ 81 extern unsigned fscache_defer_lookup; 82 extern unsigned fscache_defer_create; 83 extern unsigned fscache_debug; 84 extern struct kobject *fscache_root; 85 86 extern int fscache_wait_bit(void *); 87 extern int fscache_wait_bit_interruptible(void *); 88 89 /* 90 * object.c 91 */ 92 extern const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5]; 93 94 extern void fscache_withdrawing_object(struct fscache_cache *, 95 struct fscache_object *); 96 extern void fscache_enqueue_object(struct fscache_object *); 97 98 /* 99 * object-list.c 100 */ 101 #ifdef CONFIG_FSCACHE_OBJECT_LIST 102 extern const struct file_operations fscache_objlist_fops; 103 104 extern void fscache_objlist_add(struct fscache_object *); 105 #else 106 #define fscache_objlist_add(object) do {} while(0) 107 #endif 108 109 /* 110 * operation.c 111 */ 112 extern int fscache_submit_exclusive_op(struct fscache_object *, 113 struct fscache_operation *); 114 extern int fscache_submit_op(struct fscache_object *, 115 struct fscache_operation *); 116 extern int fscache_cancel_op(struct fscache_operation *); 117 extern void fscache_abort_object(struct fscache_object *); 118 extern void fscache_start_operations(struct fscache_object *); 119 extern void fscache_operation_gc(struct work_struct *); 120 121 /* 122 * proc.c 123 */ 124 #ifdef CONFIG_PROC_FS 125 extern int __init fscache_proc_init(void); 126 extern void fscache_proc_cleanup(void); 127 #else 128 #define fscache_proc_init() (0) 129 #define fscache_proc_cleanup() do {} while (0) 130 #endif 131 132 /* 133 * stats.c 134 */ 135 #ifdef CONFIG_FSCACHE_STATS 136 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS]; 137 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS]; 138 139 extern atomic_t fscache_n_op_pend; 140 extern atomic_t fscache_n_op_run; 141 extern atomic_t fscache_n_op_enqueue; 142 extern atomic_t fscache_n_op_deferred_release; 143 extern atomic_t fscache_n_op_release; 144 extern atomic_t fscache_n_op_gc; 145 extern atomic_t fscache_n_op_cancelled; 146 extern atomic_t fscache_n_op_rejected; 147 148 extern atomic_t fscache_n_attr_changed; 149 extern atomic_t fscache_n_attr_changed_ok; 150 extern atomic_t fscache_n_attr_changed_nobufs; 151 extern atomic_t fscache_n_attr_changed_nomem; 152 extern atomic_t fscache_n_attr_changed_calls; 153 154 extern atomic_t fscache_n_allocs; 155 extern atomic_t fscache_n_allocs_ok; 156 extern atomic_t fscache_n_allocs_wait; 157 extern atomic_t fscache_n_allocs_nobufs; 158 extern atomic_t fscache_n_allocs_intr; 159 extern atomic_t fscache_n_allocs_object_dead; 160 extern atomic_t fscache_n_alloc_ops; 161 extern atomic_t fscache_n_alloc_op_waits; 162 163 extern atomic_t fscache_n_retrievals; 164 extern atomic_t fscache_n_retrievals_ok; 165 extern atomic_t fscache_n_retrievals_wait; 166 extern atomic_t fscache_n_retrievals_nodata; 167 extern atomic_t fscache_n_retrievals_nobufs; 168 extern atomic_t fscache_n_retrievals_intr; 169 extern atomic_t fscache_n_retrievals_nomem; 170 extern atomic_t fscache_n_retrievals_object_dead; 171 extern atomic_t fscache_n_retrieval_ops; 172 extern atomic_t fscache_n_retrieval_op_waits; 173 174 extern atomic_t fscache_n_stores; 175 extern atomic_t fscache_n_stores_ok; 176 extern atomic_t fscache_n_stores_again; 177 extern atomic_t fscache_n_stores_nobufs; 178 extern atomic_t fscache_n_stores_oom; 179 extern atomic_t fscache_n_store_ops; 180 extern atomic_t fscache_n_store_calls; 181 extern atomic_t fscache_n_store_pages; 182 extern atomic_t fscache_n_store_radix_deletes; 183 extern atomic_t fscache_n_store_pages_over_limit; 184 185 extern atomic_t fscache_n_store_vmscan_not_storing; 186 extern atomic_t fscache_n_store_vmscan_gone; 187 extern atomic_t fscache_n_store_vmscan_busy; 188 extern atomic_t fscache_n_store_vmscan_cancelled; 189 190 extern atomic_t fscache_n_marks; 191 extern atomic_t fscache_n_uncaches; 192 193 extern atomic_t fscache_n_acquires; 194 extern atomic_t fscache_n_acquires_null; 195 extern atomic_t fscache_n_acquires_no_cache; 196 extern atomic_t fscache_n_acquires_ok; 197 extern atomic_t fscache_n_acquires_nobufs; 198 extern atomic_t fscache_n_acquires_oom; 199 200 extern atomic_t fscache_n_updates; 201 extern atomic_t fscache_n_updates_null; 202 extern atomic_t fscache_n_updates_run; 203 204 extern atomic_t fscache_n_relinquishes; 205 extern atomic_t fscache_n_relinquishes_null; 206 extern atomic_t fscache_n_relinquishes_waitcrt; 207 extern atomic_t fscache_n_relinquishes_retire; 208 209 extern atomic_t fscache_n_cookie_index; 210 extern atomic_t fscache_n_cookie_data; 211 extern atomic_t fscache_n_cookie_special; 212 213 extern atomic_t fscache_n_object_alloc; 214 extern atomic_t fscache_n_object_no_alloc; 215 extern atomic_t fscache_n_object_lookups; 216 extern atomic_t fscache_n_object_lookups_negative; 217 extern atomic_t fscache_n_object_lookups_positive; 218 extern atomic_t fscache_n_object_lookups_timed_out; 219 extern atomic_t fscache_n_object_created; 220 extern atomic_t fscache_n_object_avail; 221 extern atomic_t fscache_n_object_dead; 222 223 extern atomic_t fscache_n_checkaux_none; 224 extern atomic_t fscache_n_checkaux_okay; 225 extern atomic_t fscache_n_checkaux_update; 226 extern atomic_t fscache_n_checkaux_obsolete; 227 228 extern atomic_t fscache_n_cop_alloc_object; 229 extern atomic_t fscache_n_cop_lookup_object; 230 extern atomic_t fscache_n_cop_lookup_complete; 231 extern atomic_t fscache_n_cop_grab_object; 232 extern atomic_t fscache_n_cop_update_object; 233 extern atomic_t fscache_n_cop_drop_object; 234 extern atomic_t fscache_n_cop_put_object; 235 extern atomic_t fscache_n_cop_sync_cache; 236 extern atomic_t fscache_n_cop_attr_changed; 237 extern atomic_t fscache_n_cop_read_or_alloc_page; 238 extern atomic_t fscache_n_cop_read_or_alloc_pages; 239 extern atomic_t fscache_n_cop_allocate_page; 240 extern atomic_t fscache_n_cop_allocate_pages; 241 extern atomic_t fscache_n_cop_write_page; 242 extern atomic_t fscache_n_cop_uncache_page; 243 extern atomic_t fscache_n_cop_dissociate_pages; 244 245 static inline void fscache_stat(atomic_t *stat) 246 { 247 atomic_inc(stat); 248 } 249 250 static inline void fscache_stat_d(atomic_t *stat) 251 { 252 atomic_dec(stat); 253 } 254 255 #define __fscache_stat(stat) (stat) 256 257 extern const struct file_operations fscache_stats_fops; 258 #else 259 260 #define __fscache_stat(stat) (NULL) 261 #define fscache_stat(stat) do {} while (0) 262 #define fscache_stat_d(stat) do {} while (0) 263 #endif 264 265 /* 266 * raise an event on an object 267 * - if the event is not masked for that object, then the object is 268 * queued for attention by the thread pool. 269 */ 270 static inline void fscache_raise_event(struct fscache_object *object, 271 unsigned event) 272 { 273 if (!test_and_set_bit(event, &object->events) && 274 test_bit(event, &object->event_mask)) 275 fscache_enqueue_object(object); 276 } 277 278 /* 279 * drop a reference to a cookie 280 */ 281 static inline void fscache_cookie_put(struct fscache_cookie *cookie) 282 { 283 BUG_ON(atomic_read(&cookie->usage) <= 0); 284 if (atomic_dec_and_test(&cookie->usage)) 285 __fscache_cookie_put(cookie); 286 } 287 288 /* 289 * get an extra reference to a netfs retrieval context 290 */ 291 static inline 292 void *fscache_get_context(struct fscache_cookie *cookie, void *context) 293 { 294 if (cookie->def->get_context) 295 cookie->def->get_context(cookie->netfs_data, context); 296 return context; 297 } 298 299 /* 300 * release a reference to a netfs retrieval context 301 */ 302 static inline 303 void fscache_put_context(struct fscache_cookie *cookie, void *context) 304 { 305 if (cookie->def->put_context) 306 cookie->def->put_context(cookie->netfs_data, context); 307 } 308 309 /*****************************************************************************/ 310 /* 311 * debug tracing 312 */ 313 #define dbgprintk(FMT, ...) \ 314 printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__) 315 316 /* make sure we maintain the format strings, even when debugging is disabled */ 317 static inline __attribute__((format(printf, 1, 2))) 318 void _dbprintk(const char *fmt, ...) 319 { 320 } 321 322 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 323 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 324 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__) 325 326 #define kjournal(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__) 327 328 #ifdef __KDEBUG 329 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__) 330 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__) 331 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__) 332 333 #elif defined(CONFIG_FSCACHE_DEBUG) 334 #define _enter(FMT, ...) \ 335 do { \ 336 if (__do_kdebug(ENTER)) \ 337 kenter(FMT, ##__VA_ARGS__); \ 338 } while (0) 339 340 #define _leave(FMT, ...) \ 341 do { \ 342 if (__do_kdebug(LEAVE)) \ 343 kleave(FMT, ##__VA_ARGS__); \ 344 } while (0) 345 346 #define _debug(FMT, ...) \ 347 do { \ 348 if (__do_kdebug(DEBUG)) \ 349 kdebug(FMT, ##__VA_ARGS__); \ 350 } while (0) 351 352 #else 353 #define _enter(FMT, ...) _dbprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 354 #define _leave(FMT, ...) _dbprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 355 #define _debug(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__) 356 #endif 357 358 /* 359 * determine whether a particular optional debugging point should be logged 360 * - we need to go through three steps to persuade cpp to correctly join the 361 * shorthand in FSCACHE_DEBUG_LEVEL with its prefix 362 */ 363 #define ____do_kdebug(LEVEL, POINT) \ 364 unlikely((fscache_debug & \ 365 (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3)))) 366 #define ___do_kdebug(LEVEL, POINT) \ 367 ____do_kdebug(LEVEL, POINT) 368 #define __do_kdebug(POINT) \ 369 ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT) 370 371 #define FSCACHE_DEBUG_CACHE 0 372 #define FSCACHE_DEBUG_COOKIE 1 373 #define FSCACHE_DEBUG_PAGE 2 374 #define FSCACHE_DEBUG_OPERATION 3 375 376 #define FSCACHE_POINT_ENTER 1 377 #define FSCACHE_POINT_LEAVE 2 378 #define FSCACHE_POINT_DEBUG 4 379 380 #ifndef FSCACHE_DEBUG_LEVEL 381 #define FSCACHE_DEBUG_LEVEL CACHE 382 #endif 383 384 /* 385 * assertions 386 */ 387 #if 1 /* defined(__KDEBUGALL) */ 388 389 #define ASSERT(X) \ 390 do { \ 391 if (unlikely(!(X))) { \ 392 printk(KERN_ERR "\n"); \ 393 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 394 BUG(); \ 395 } \ 396 } while (0) 397 398 #define ASSERTCMP(X, OP, Y) \ 399 do { \ 400 if (unlikely(!((X) OP (Y)))) { \ 401 printk(KERN_ERR "\n"); \ 402 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 403 printk(KERN_ERR "%lx " #OP " %lx is false\n", \ 404 (unsigned long)(X), (unsigned long)(Y)); \ 405 BUG(); \ 406 } \ 407 } while (0) 408 409 #define ASSERTIF(C, X) \ 410 do { \ 411 if (unlikely((C) && !(X))) { \ 412 printk(KERN_ERR "\n"); \ 413 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 414 BUG(); \ 415 } \ 416 } while (0) 417 418 #define ASSERTIFCMP(C, X, OP, Y) \ 419 do { \ 420 if (unlikely((C) && !((X) OP (Y)))) { \ 421 printk(KERN_ERR "\n"); \ 422 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 423 printk(KERN_ERR "%lx " #OP " %lx is false\n", \ 424 (unsigned long)(X), (unsigned long)(Y)); \ 425 BUG(); \ 426 } \ 427 } while (0) 428 429 #else 430 431 #define ASSERT(X) do {} while (0) 432 #define ASSERTCMP(X, OP, Y) do {} while (0) 433 #define ASSERTIF(C, X) do {} while (0) 434 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0) 435 436 #endif /* assert or not */ 437