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 * - fscache_thread_lock 21 * 22 */ 23 24 #include <linux/fscache-cache.h> 25 #include <linux/sched.h> 26 27 #define FSCACHE_MIN_THREADS 4 28 #define FSCACHE_MAX_THREADS 32 29 30 /* 31 * cache.c 32 */ 33 extern struct list_head fscache_cache_list; 34 extern struct rw_semaphore fscache_addremove_sem; 35 36 extern struct fscache_cache *fscache_select_cache_for_object( 37 struct fscache_cookie *); 38 39 /* 40 * cookie.c 41 */ 42 extern struct kmem_cache *fscache_cookie_jar; 43 44 extern void fscache_cookie_init_once(void *); 45 extern void __fscache_cookie_put(struct fscache_cookie *); 46 47 /* 48 * fsdef.c 49 */ 50 extern struct fscache_cookie fscache_fsdef_index; 51 extern struct fscache_cookie_def fscache_fsdef_netfs_def; 52 53 /* 54 * histogram.c 55 */ 56 #ifdef CONFIG_FSCACHE_HISTOGRAM 57 extern atomic_t fscache_obj_instantiate_histogram[HZ]; 58 extern atomic_t fscache_objs_histogram[HZ]; 59 extern atomic_t fscache_ops_histogram[HZ]; 60 extern atomic_t fscache_retrieval_delay_histogram[HZ]; 61 extern atomic_t fscache_retrieval_histogram[HZ]; 62 63 static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif) 64 { 65 unsigned long jif = jiffies - start_jif; 66 if (jif >= HZ) 67 jif = HZ - 1; 68 atomic_inc(&histogram[jif]); 69 } 70 71 extern const struct file_operations fscache_histogram_fops; 72 73 #else 74 #define fscache_hist(hist, start_jif) do {} while (0) 75 #endif 76 77 /* 78 * main.c 79 */ 80 extern unsigned fscache_defer_lookup; 81 extern unsigned fscache_defer_create; 82 extern unsigned fscache_debug; 83 extern struct kobject *fscache_root; 84 85 extern int fscache_wait_bit(void *); 86 extern int fscache_wait_bit_interruptible(void *); 87 88 /* 89 * object.c 90 */ 91 extern void fscache_withdrawing_object(struct fscache_cache *, 92 struct fscache_object *); 93 extern void fscache_enqueue_object(struct fscache_object *); 94 95 /* 96 * operation.c 97 */ 98 extern int fscache_submit_exclusive_op(struct fscache_object *, 99 struct fscache_operation *); 100 extern int fscache_submit_op(struct fscache_object *, 101 struct fscache_operation *); 102 extern void fscache_abort_object(struct fscache_object *); 103 extern void fscache_start_operations(struct fscache_object *); 104 extern void fscache_operation_gc(struct work_struct *); 105 106 /* 107 * proc.c 108 */ 109 #ifdef CONFIG_PROC_FS 110 extern int __init fscache_proc_init(void); 111 extern void fscache_proc_cleanup(void); 112 #else 113 #define fscache_proc_init() (0) 114 #define fscache_proc_cleanup() do {} while (0) 115 #endif 116 117 /* 118 * stats.c 119 */ 120 #ifdef CONFIG_FSCACHE_STATS 121 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS]; 122 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS]; 123 124 extern atomic_t fscache_n_op_pend; 125 extern atomic_t fscache_n_op_run; 126 extern atomic_t fscache_n_op_enqueue; 127 extern atomic_t fscache_n_op_deferred_release; 128 extern atomic_t fscache_n_op_release; 129 extern atomic_t fscache_n_op_gc; 130 131 extern atomic_t fscache_n_attr_changed; 132 extern atomic_t fscache_n_attr_changed_ok; 133 extern atomic_t fscache_n_attr_changed_nobufs; 134 extern atomic_t fscache_n_attr_changed_nomem; 135 extern atomic_t fscache_n_attr_changed_calls; 136 137 extern atomic_t fscache_n_allocs; 138 extern atomic_t fscache_n_allocs_ok; 139 extern atomic_t fscache_n_allocs_wait; 140 extern atomic_t fscache_n_allocs_nobufs; 141 extern atomic_t fscache_n_alloc_ops; 142 extern atomic_t fscache_n_alloc_op_waits; 143 144 extern atomic_t fscache_n_retrievals; 145 extern atomic_t fscache_n_retrievals_ok; 146 extern atomic_t fscache_n_retrievals_wait; 147 extern atomic_t fscache_n_retrievals_nodata; 148 extern atomic_t fscache_n_retrievals_nobufs; 149 extern atomic_t fscache_n_retrievals_intr; 150 extern atomic_t fscache_n_retrievals_nomem; 151 extern atomic_t fscache_n_retrieval_ops; 152 extern atomic_t fscache_n_retrieval_op_waits; 153 154 extern atomic_t fscache_n_stores; 155 extern atomic_t fscache_n_stores_ok; 156 extern atomic_t fscache_n_stores_again; 157 extern atomic_t fscache_n_stores_nobufs; 158 extern atomic_t fscache_n_stores_oom; 159 extern atomic_t fscache_n_store_ops; 160 extern atomic_t fscache_n_store_calls; 161 162 extern atomic_t fscache_n_marks; 163 extern atomic_t fscache_n_uncaches; 164 165 extern atomic_t fscache_n_acquires; 166 extern atomic_t fscache_n_acquires_null; 167 extern atomic_t fscache_n_acquires_no_cache; 168 extern atomic_t fscache_n_acquires_ok; 169 extern atomic_t fscache_n_acquires_nobufs; 170 extern atomic_t fscache_n_acquires_oom; 171 172 extern atomic_t fscache_n_updates; 173 extern atomic_t fscache_n_updates_null; 174 extern atomic_t fscache_n_updates_run; 175 176 extern atomic_t fscache_n_relinquishes; 177 extern atomic_t fscache_n_relinquishes_null; 178 extern atomic_t fscache_n_relinquishes_waitcrt; 179 180 extern atomic_t fscache_n_cookie_index; 181 extern atomic_t fscache_n_cookie_data; 182 extern atomic_t fscache_n_cookie_special; 183 184 extern atomic_t fscache_n_object_alloc; 185 extern atomic_t fscache_n_object_no_alloc; 186 extern atomic_t fscache_n_object_lookups; 187 extern atomic_t fscache_n_object_lookups_negative; 188 extern atomic_t fscache_n_object_lookups_positive; 189 extern atomic_t fscache_n_object_created; 190 extern atomic_t fscache_n_object_avail; 191 extern atomic_t fscache_n_object_dead; 192 193 extern atomic_t fscache_n_checkaux_none; 194 extern atomic_t fscache_n_checkaux_okay; 195 extern atomic_t fscache_n_checkaux_update; 196 extern atomic_t fscache_n_checkaux_obsolete; 197 198 static inline void fscache_stat(atomic_t *stat) 199 { 200 atomic_inc(stat); 201 } 202 203 extern const struct file_operations fscache_stats_fops; 204 #else 205 206 #define fscache_stat(stat) do {} while (0) 207 #endif 208 209 /* 210 * raise an event on an object 211 * - if the event is not masked for that object, then the object is 212 * queued for attention by the thread pool. 213 */ 214 static inline void fscache_raise_event(struct fscache_object *object, 215 unsigned event) 216 { 217 if (!test_and_set_bit(event, &object->events) && 218 test_bit(event, &object->event_mask)) 219 fscache_enqueue_object(object); 220 } 221 222 /* 223 * drop a reference to a cookie 224 */ 225 static inline void fscache_cookie_put(struct fscache_cookie *cookie) 226 { 227 BUG_ON(atomic_read(&cookie->usage) <= 0); 228 if (atomic_dec_and_test(&cookie->usage)) 229 __fscache_cookie_put(cookie); 230 } 231 232 /* 233 * get an extra reference to a netfs retrieval context 234 */ 235 static inline 236 void *fscache_get_context(struct fscache_cookie *cookie, void *context) 237 { 238 if (cookie->def->get_context) 239 cookie->def->get_context(cookie->netfs_data, context); 240 return context; 241 } 242 243 /* 244 * release a reference to a netfs retrieval context 245 */ 246 static inline 247 void fscache_put_context(struct fscache_cookie *cookie, void *context) 248 { 249 if (cookie->def->put_context) 250 cookie->def->put_context(cookie->netfs_data, context); 251 } 252 253 /*****************************************************************************/ 254 /* 255 * debug tracing 256 */ 257 #define dbgprintk(FMT, ...) \ 258 printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__) 259 260 /* make sure we maintain the format strings, even when debugging is disabled */ 261 static inline __attribute__((format(printf, 1, 2))) 262 void _dbprintk(const char *fmt, ...) 263 { 264 } 265 266 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 267 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 268 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__) 269 270 #define kjournal(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__) 271 272 #ifdef __KDEBUG 273 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__) 274 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__) 275 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__) 276 277 #elif defined(CONFIG_FSCACHE_DEBUG) 278 #define _enter(FMT, ...) \ 279 do { \ 280 if (__do_kdebug(ENTER)) \ 281 kenter(FMT, ##__VA_ARGS__); \ 282 } while (0) 283 284 #define _leave(FMT, ...) \ 285 do { \ 286 if (__do_kdebug(LEAVE)) \ 287 kleave(FMT, ##__VA_ARGS__); \ 288 } while (0) 289 290 #define _debug(FMT, ...) \ 291 do { \ 292 if (__do_kdebug(DEBUG)) \ 293 kdebug(FMT, ##__VA_ARGS__); \ 294 } while (0) 295 296 #else 297 #define _enter(FMT, ...) _dbprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 298 #define _leave(FMT, ...) _dbprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 299 #define _debug(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__) 300 #endif 301 302 /* 303 * determine whether a particular optional debugging point should be logged 304 * - we need to go through three steps to persuade cpp to correctly join the 305 * shorthand in FSCACHE_DEBUG_LEVEL with its prefix 306 */ 307 #define ____do_kdebug(LEVEL, POINT) \ 308 unlikely((fscache_debug & \ 309 (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3)))) 310 #define ___do_kdebug(LEVEL, POINT) \ 311 ____do_kdebug(LEVEL, POINT) 312 #define __do_kdebug(POINT) \ 313 ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT) 314 315 #define FSCACHE_DEBUG_CACHE 0 316 #define FSCACHE_DEBUG_COOKIE 1 317 #define FSCACHE_DEBUG_PAGE 2 318 #define FSCACHE_DEBUG_OPERATION 3 319 320 #define FSCACHE_POINT_ENTER 1 321 #define FSCACHE_POINT_LEAVE 2 322 #define FSCACHE_POINT_DEBUG 4 323 324 #ifndef FSCACHE_DEBUG_LEVEL 325 #define FSCACHE_DEBUG_LEVEL CACHE 326 #endif 327 328 /* 329 * assertions 330 */ 331 #if 1 /* defined(__KDEBUGALL) */ 332 333 #define ASSERT(X) \ 334 do { \ 335 if (unlikely(!(X))) { \ 336 printk(KERN_ERR "\n"); \ 337 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 338 BUG(); \ 339 } \ 340 } while (0) 341 342 #define ASSERTCMP(X, OP, Y) \ 343 do { \ 344 if (unlikely(!((X) OP (Y)))) { \ 345 printk(KERN_ERR "\n"); \ 346 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 347 printk(KERN_ERR "%lx " #OP " %lx is false\n", \ 348 (unsigned long)(X), (unsigned long)(Y)); \ 349 BUG(); \ 350 } \ 351 } while (0) 352 353 #define ASSERTIF(C, X) \ 354 do { \ 355 if (unlikely((C) && !(X))) { \ 356 printk(KERN_ERR "\n"); \ 357 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 358 BUG(); \ 359 } \ 360 } while (0) 361 362 #define ASSERTIFCMP(C, X, OP, Y) \ 363 do { \ 364 if (unlikely((C) && !((X) OP (Y)))) { \ 365 printk(KERN_ERR "\n"); \ 366 printk(KERN_ERR "FS-Cache: Assertion failed\n"); \ 367 printk(KERN_ERR "%lx " #OP " %lx is false\n", \ 368 (unsigned long)(X), (unsigned long)(Y)); \ 369 BUG(); \ 370 } \ 371 } while (0) 372 373 #else 374 375 #define ASSERT(X) do {} while (0) 376 #define ASSERTCMP(X, OP, Y) do {} while (0) 377 #define ASSERTIF(C, X) do {} while (0) 378 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0) 379 380 #endif /* assert or not */ 381