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