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 97 /* 98 * object.c 99 */ 100 extern const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5]; 101 102 extern void fscache_withdrawing_object(struct fscache_cache *, 103 struct fscache_object *); 104 extern void fscache_enqueue_object(struct fscache_object *); 105 106 /* 107 * object-list.c 108 */ 109 #ifdef CONFIG_FSCACHE_OBJECT_LIST 110 extern const struct file_operations fscache_objlist_fops; 111 112 extern void fscache_objlist_add(struct fscache_object *); 113 #else 114 #define fscache_objlist_add(object) do {} while(0) 115 #endif 116 117 /* 118 * operation.c 119 */ 120 extern int fscache_submit_exclusive_op(struct fscache_object *, 121 struct fscache_operation *); 122 extern int fscache_submit_op(struct fscache_object *, 123 struct fscache_operation *); 124 extern int fscache_cancel_op(struct fscache_operation *); 125 extern void fscache_abort_object(struct fscache_object *); 126 extern void fscache_start_operations(struct fscache_object *); 127 extern void fscache_operation_gc(struct work_struct *); 128 129 /* 130 * proc.c 131 */ 132 #ifdef CONFIG_PROC_FS 133 extern int __init fscache_proc_init(void); 134 extern void fscache_proc_cleanup(void); 135 #else 136 #define fscache_proc_init() (0) 137 #define fscache_proc_cleanup() do {} while (0) 138 #endif 139 140 /* 141 * stats.c 142 */ 143 #ifdef CONFIG_FSCACHE_STATS 144 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS]; 145 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS]; 146 147 extern atomic_t fscache_n_op_pend; 148 extern atomic_t fscache_n_op_run; 149 extern atomic_t fscache_n_op_enqueue; 150 extern atomic_t fscache_n_op_deferred_release; 151 extern atomic_t fscache_n_op_release; 152 extern atomic_t fscache_n_op_gc; 153 extern atomic_t fscache_n_op_cancelled; 154 extern atomic_t fscache_n_op_rejected; 155 156 extern atomic_t fscache_n_attr_changed; 157 extern atomic_t fscache_n_attr_changed_ok; 158 extern atomic_t fscache_n_attr_changed_nobufs; 159 extern atomic_t fscache_n_attr_changed_nomem; 160 extern atomic_t fscache_n_attr_changed_calls; 161 162 extern atomic_t fscache_n_allocs; 163 extern atomic_t fscache_n_allocs_ok; 164 extern atomic_t fscache_n_allocs_wait; 165 extern atomic_t fscache_n_allocs_nobufs; 166 extern atomic_t fscache_n_allocs_intr; 167 extern atomic_t fscache_n_allocs_object_dead; 168 extern atomic_t fscache_n_alloc_ops; 169 extern atomic_t fscache_n_alloc_op_waits; 170 171 extern atomic_t fscache_n_retrievals; 172 extern atomic_t fscache_n_retrievals_ok; 173 extern atomic_t fscache_n_retrievals_wait; 174 extern atomic_t fscache_n_retrievals_nodata; 175 extern atomic_t fscache_n_retrievals_nobufs; 176 extern atomic_t fscache_n_retrievals_intr; 177 extern atomic_t fscache_n_retrievals_nomem; 178 extern atomic_t fscache_n_retrievals_object_dead; 179 extern atomic_t fscache_n_retrieval_ops; 180 extern atomic_t fscache_n_retrieval_op_waits; 181 182 extern atomic_t fscache_n_stores; 183 extern atomic_t fscache_n_stores_ok; 184 extern atomic_t fscache_n_stores_again; 185 extern atomic_t fscache_n_stores_nobufs; 186 extern atomic_t fscache_n_stores_oom; 187 extern atomic_t fscache_n_store_ops; 188 extern atomic_t fscache_n_store_calls; 189 extern atomic_t fscache_n_store_pages; 190 extern atomic_t fscache_n_store_radix_deletes; 191 extern atomic_t fscache_n_store_pages_over_limit; 192 193 extern atomic_t fscache_n_store_vmscan_not_storing; 194 extern atomic_t fscache_n_store_vmscan_gone; 195 extern atomic_t fscache_n_store_vmscan_busy; 196 extern atomic_t fscache_n_store_vmscan_cancelled; 197 198 extern atomic_t fscache_n_marks; 199 extern atomic_t fscache_n_uncaches; 200 201 extern atomic_t fscache_n_acquires; 202 extern atomic_t fscache_n_acquires_null; 203 extern atomic_t fscache_n_acquires_no_cache; 204 extern atomic_t fscache_n_acquires_ok; 205 extern atomic_t fscache_n_acquires_nobufs; 206 extern atomic_t fscache_n_acquires_oom; 207 208 extern atomic_t fscache_n_updates; 209 extern atomic_t fscache_n_updates_null; 210 extern atomic_t fscache_n_updates_run; 211 212 extern atomic_t fscache_n_relinquishes; 213 extern atomic_t fscache_n_relinquishes_null; 214 extern atomic_t fscache_n_relinquishes_waitcrt; 215 extern atomic_t fscache_n_relinquishes_retire; 216 217 extern atomic_t fscache_n_cookie_index; 218 extern atomic_t fscache_n_cookie_data; 219 extern atomic_t fscache_n_cookie_special; 220 221 extern atomic_t fscache_n_object_alloc; 222 extern atomic_t fscache_n_object_no_alloc; 223 extern atomic_t fscache_n_object_lookups; 224 extern atomic_t fscache_n_object_lookups_negative; 225 extern atomic_t fscache_n_object_lookups_positive; 226 extern atomic_t fscache_n_object_lookups_timed_out; 227 extern atomic_t fscache_n_object_created; 228 extern atomic_t fscache_n_object_avail; 229 extern atomic_t fscache_n_object_dead; 230 231 extern atomic_t fscache_n_checkaux_none; 232 extern atomic_t fscache_n_checkaux_okay; 233 extern atomic_t fscache_n_checkaux_update; 234 extern atomic_t fscache_n_checkaux_obsolete; 235 236 extern atomic_t fscache_n_cop_alloc_object; 237 extern atomic_t fscache_n_cop_lookup_object; 238 extern atomic_t fscache_n_cop_lookup_complete; 239 extern atomic_t fscache_n_cop_grab_object; 240 extern atomic_t fscache_n_cop_update_object; 241 extern atomic_t fscache_n_cop_drop_object; 242 extern atomic_t fscache_n_cop_put_object; 243 extern atomic_t fscache_n_cop_sync_cache; 244 extern atomic_t fscache_n_cop_attr_changed; 245 extern atomic_t fscache_n_cop_read_or_alloc_page; 246 extern atomic_t fscache_n_cop_read_or_alloc_pages; 247 extern atomic_t fscache_n_cop_allocate_page; 248 extern atomic_t fscache_n_cop_allocate_pages; 249 extern atomic_t fscache_n_cop_write_page; 250 extern atomic_t fscache_n_cop_uncache_page; 251 extern atomic_t fscache_n_cop_dissociate_pages; 252 253 static inline void fscache_stat(atomic_t *stat) 254 { 255 atomic_inc(stat); 256 } 257 258 static inline void fscache_stat_d(atomic_t *stat) 259 { 260 atomic_dec(stat); 261 } 262 263 #define __fscache_stat(stat) (stat) 264 265 extern const struct file_operations fscache_stats_fops; 266 #else 267 268 #define __fscache_stat(stat) (NULL) 269 #define fscache_stat(stat) do {} while (0) 270 #define fscache_stat_d(stat) do {} while (0) 271 #endif 272 273 /* 274 * raise an event on an object 275 * - if the event is not masked for that object, then the object is 276 * queued for attention by the thread pool. 277 */ 278 static inline void fscache_raise_event(struct fscache_object *object, 279 unsigned event) 280 { 281 if (!test_and_set_bit(event, &object->events) && 282 test_bit(event, &object->event_mask)) 283 fscache_enqueue_object(object); 284 } 285 286 /* 287 * drop a reference to a cookie 288 */ 289 static inline void fscache_cookie_put(struct fscache_cookie *cookie) 290 { 291 BUG_ON(atomic_read(&cookie->usage) <= 0); 292 if (atomic_dec_and_test(&cookie->usage)) 293 __fscache_cookie_put(cookie); 294 } 295 296 /* 297 * get an extra reference to a netfs retrieval context 298 */ 299 static inline 300 void *fscache_get_context(struct fscache_cookie *cookie, void *context) 301 { 302 if (cookie->def->get_context) 303 cookie->def->get_context(cookie->netfs_data, context); 304 return context; 305 } 306 307 /* 308 * release a reference to a netfs retrieval context 309 */ 310 static inline 311 void fscache_put_context(struct fscache_cookie *cookie, void *context) 312 { 313 if (cookie->def->put_context) 314 cookie->def->put_context(cookie->netfs_data, context); 315 } 316 317 /*****************************************************************************/ 318 /* 319 * debug tracing 320 */ 321 #define dbgprintk(FMT, ...) \ 322 printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__) 323 324 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 325 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 326 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__) 327 328 #define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__) 329 330 #ifdef __KDEBUG 331 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__) 332 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__) 333 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__) 334 335 #elif defined(CONFIG_FSCACHE_DEBUG) 336 #define _enter(FMT, ...) \ 337 do { \ 338 if (__do_kdebug(ENTER)) \ 339 kenter(FMT, ##__VA_ARGS__); \ 340 } while (0) 341 342 #define _leave(FMT, ...) \ 343 do { \ 344 if (__do_kdebug(LEAVE)) \ 345 kleave(FMT, ##__VA_ARGS__); \ 346 } while (0) 347 348 #define _debug(FMT, ...) \ 349 do { \ 350 if (__do_kdebug(DEBUG)) \ 351 kdebug(FMT, ##__VA_ARGS__); \ 352 } while (0) 353 354 #else 355 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__) 356 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 357 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__) 358 #endif 359 360 /* 361 * determine whether a particular optional debugging point should be logged 362 * - we need to go through three steps to persuade cpp to correctly join the 363 * shorthand in FSCACHE_DEBUG_LEVEL with its prefix 364 */ 365 #define ____do_kdebug(LEVEL, POINT) \ 366 unlikely((fscache_debug & \ 367 (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3)))) 368 #define ___do_kdebug(LEVEL, POINT) \ 369 ____do_kdebug(LEVEL, POINT) 370 #define __do_kdebug(POINT) \ 371 ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT) 372 373 #define FSCACHE_DEBUG_CACHE 0 374 #define FSCACHE_DEBUG_COOKIE 1 375 #define FSCACHE_DEBUG_PAGE 2 376 #define FSCACHE_DEBUG_OPERATION 3 377 378 #define FSCACHE_POINT_ENTER 1 379 #define FSCACHE_POINT_LEAVE 2 380 #define FSCACHE_POINT_DEBUG 4 381 382 #ifndef FSCACHE_DEBUG_LEVEL 383 #define FSCACHE_DEBUG_LEVEL CACHE 384 #endif 385 386 /* 387 * assertions 388 */ 389 #if 1 /* defined(__KDEBUGALL) */ 390 391 #define ASSERT(X) \ 392 do { \ 393 if (unlikely(!(X))) { \ 394 printk(KERN_ERR "\n"); \ 395 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 396 BUG(); \ 397 } \ 398 } while (0) 399 400 #define ASSERTCMP(X, OP, Y) \ 401 do { \ 402 if (unlikely(!((X) OP (Y)))) { \ 403 printk(KERN_ERR "\n"); \ 404 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 405 printk(KERN_ERR "%lx " #OP " %lx is false\n", \ 406 (unsigned long)(X), (unsigned long)(Y)); \ 407 BUG(); \ 408 } \ 409 } while (0) 410 411 #define ASSERTIF(C, X) \ 412 do { \ 413 if (unlikely((C) && !(X))) { \ 414 printk(KERN_ERR "\n"); \ 415 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 416 BUG(); \ 417 } \ 418 } while (0) 419 420 #define ASSERTIFCMP(C, X, OP, Y) \ 421 do { \ 422 if (unlikely((C) && !((X) OP (Y)))) { \ 423 printk(KERN_ERR "\n"); \ 424 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 425 printk(KERN_ERR "%lx " #OP " %lx is false\n", \ 426 (unsigned long)(X), (unsigned long)(Y)); \ 427 BUG(); \ 428 } \ 429 } while (0) 430 431 #else 432 433 #define ASSERT(X) do {} while (0) 434 #define ASSERTCMP(X, OP, Y) do {} while (0) 435 #define ASSERTIF(C, X) do {} while (0) 436 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0) 437 438 #endif /* assert or not */ 439