fs/fscache/internal.h

   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  * fsc-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  * fsc-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  * fsc-fsdef.c
  49  */
  50 extern struct fscache_cookie fscache_fsdef_index;
  51 extern struct fscache_cookie_def fscache_fsdef_netfs_def;
  52
  53 /*
  54  * fsc-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  * fsc-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 /*
  86  * fsc-proc.c
  87  */
  88 #ifdef CONFIG_PROC_FS
  89 extern int __init fscache_proc_init(void);
  90 extern void fscache_proc_cleanup(void);
  91 #else
  92 #define fscache_proc_init()     (0)
  93 #define fscache_proc_cleanup()  do {} while (0)
  94 #endif
  95
  96 /*
  97  * fsc-stats.c
  98  */
  99 #ifdef CONFIG_FSCACHE_STATS
 100 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS];
 101 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS];
 102
 103 extern atomic_t fscache_n_op_pend;
 104 extern atomic_t fscache_n_op_run;
 105 extern atomic_t fscache_n_op_enqueue;
 106 extern atomic_t fscache_n_op_deferred_release;
 107 extern atomic_t fscache_n_op_release;
 108 extern atomic_t fscache_n_op_gc;
 109
 110 extern atomic_t fscache_n_attr_changed;
 111 extern atomic_t fscache_n_attr_changed_ok;
 112 extern atomic_t fscache_n_attr_changed_nobufs;
 113 extern atomic_t fscache_n_attr_changed_nomem;
 114 extern atomic_t fscache_n_attr_changed_calls;
 115
 116 extern atomic_t fscache_n_allocs;
 117 extern atomic_t fscache_n_allocs_ok;
 118 extern atomic_t fscache_n_allocs_wait;
 119 extern atomic_t fscache_n_allocs_nobufs;
 120 extern atomic_t fscache_n_alloc_ops;
 121 extern atomic_t fscache_n_alloc_op_waits;
 122
 123 extern atomic_t fscache_n_retrievals;
 124 extern atomic_t fscache_n_retrievals_ok;
 125 extern atomic_t fscache_n_retrievals_wait;
 126 extern atomic_t fscache_n_retrievals_nodata;
 127 extern atomic_t fscache_n_retrievals_nobufs;
 128 extern atomic_t fscache_n_retrievals_intr;
 129 extern atomic_t fscache_n_retrievals_nomem;
 130 extern atomic_t fscache_n_retrieval_ops;
 131 extern atomic_t fscache_n_retrieval_op_waits;
 132
 133 extern atomic_t fscache_n_stores;
 134 extern atomic_t fscache_n_stores_ok;
 135 extern atomic_t fscache_n_stores_again;
 136 extern atomic_t fscache_n_stores_nobufs;
 137 extern atomic_t fscache_n_stores_oom;
 138 extern atomic_t fscache_n_store_ops;
 139 extern atomic_t fscache_n_store_calls;
 140
 141 extern atomic_t fscache_n_marks;
 142 extern atomic_t fscache_n_uncaches;
 143
 144 extern atomic_t fscache_n_acquires;
 145 extern atomic_t fscache_n_acquires_null;
 146 extern atomic_t fscache_n_acquires_no_cache;
 147 extern atomic_t fscache_n_acquires_ok;
 148 extern atomic_t fscache_n_acquires_nobufs;
 149 extern atomic_t fscache_n_acquires_oom;
 150
 151 extern atomic_t fscache_n_updates;
 152 extern atomic_t fscache_n_updates_null;
 153 extern atomic_t fscache_n_updates_run;
 154
 155 extern atomic_t fscache_n_relinquishes;
 156 extern atomic_t fscache_n_relinquishes_null;
 157 extern atomic_t fscache_n_relinquishes_waitcrt;
 158
 159 extern atomic_t fscache_n_cookie_index;
 160 extern atomic_t fscache_n_cookie_data;
 161 extern atomic_t fscache_n_cookie_special;
 162
 163 extern atomic_t fscache_n_object_alloc;
 164 extern atomic_t fscache_n_object_no_alloc;
 165 extern atomic_t fscache_n_object_lookups;
 166 extern atomic_t fscache_n_object_lookups_negative;
 167 extern atomic_t fscache_n_object_lookups_positive;
 168 extern atomic_t fscache_n_object_created;
 169 extern atomic_t fscache_n_object_avail;
 170 extern atomic_t fscache_n_object_dead;
 171
 172 extern atomic_t fscache_n_checkaux_none;
 173 extern atomic_t fscache_n_checkaux_okay;
 174 extern atomic_t fscache_n_checkaux_update;
 175 extern atomic_t fscache_n_checkaux_obsolete;
 176
 177 static inline void fscache_stat(atomic_t *stat)
 178 {
 179         atomic_inc(stat);
 180 }
 181
 182 extern const struct file_operations fscache_stats_fops;
 183 #else
 184
 185 #define fscache_stat(stat) do {} while (0)
 186 #endif
 187
 188 /*
 189  * raise an event on an object
 190  * - if the event is not masked for that object, then the object is
 191  *   queued for attention by the thread pool.
 192  */
 193 static inline void fscache_raise_event(struct fscache_object *object,
 194                                        unsigned event)
 195 {
 196         BUG();  // TODO
 197 }
 198
 199 /*****************************************************************************/
 200 /*
 201  * debug tracing
 202  */
 203 #define dbgprintk(FMT, ...) \
 204         printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
 205
 206 /* make sure we maintain the format strings, even when debugging is disabled */
 207 static inline __attribute__((format(printf, 1, 2)))
 208 void _dbprintk(const char *fmt, ...)
 209 {
 210 }
 211
 212 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 213 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 214 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
 215
 216 #define kjournal(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__)
 217
 218 #ifdef __KDEBUG
 219 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
 220 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
 221 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
 222
 223 #elif defined(CONFIG_FSCACHE_DEBUG)
 224 #define _enter(FMT, ...)                        \
 225 do {                                            \
 226         if (__do_kdebug(ENTER))                 \
 227                 kenter(FMT, ##__VA_ARGS__);     \
 228 } while (0)
 229
 230 #define _leave(FMT, ...)                        \
 231 do {                                            \
 232         if (__do_kdebug(LEAVE))                 \
 233                 kleave(FMT, ##__VA_ARGS__);     \
 234 } while (0)
 235
 236 #define _debug(FMT, ...)                        \
 237 do {                                            \
 238         if (__do_kdebug(DEBUG))                 \
 239                 kdebug(FMT, ##__VA_ARGS__);     \
 240 } while (0)
 241
 242 #else
 243 #define _enter(FMT, ...) _dbprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 244 #define _leave(FMT, ...) _dbprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 245 #define _debug(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__)
 246 #endif
 247
 248 /*
 249  * determine whether a particular optional debugging point should be logged
 250  * - we need to go through three steps to persuade cpp to correctly join the
 251  *   shorthand in FSCACHE_DEBUG_LEVEL with its prefix
 252  */
 253 #define ____do_kdebug(LEVEL, POINT) \
 254         unlikely((fscache_debug & \
 255                   (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
 256 #define ___do_kdebug(LEVEL, POINT) \
 257         ____do_kdebug(LEVEL, POINT)
 258 #define __do_kdebug(POINT) \
 259         ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
 260
 261 #define FSCACHE_DEBUG_CACHE     0
 262 #define FSCACHE_DEBUG_COOKIE    1
 263 #define FSCACHE_DEBUG_PAGE      2
 264 #define FSCACHE_DEBUG_OPERATION 3
 265
 266 #define FSCACHE_POINT_ENTER     1
 267 #define FSCACHE_POINT_LEAVE     2
 268 #define FSCACHE_POINT_DEBUG     4
 269
 270 #ifndef FSCACHE_DEBUG_LEVEL
 271 #define FSCACHE_DEBUG_LEVEL CACHE
 272 #endif
 273
 274 /*
 275  * assertions
 276  */
 277 #if 1 /* defined(__KDEBUGALL) */
 278
 279 #define ASSERT(X)                                                       \
 280 do {                                                                    \
 281         if (unlikely(!(X))) {                                           \
 282                 printk(KERN_ERR "\n");                                  \
 283                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 284                 BUG();                                                  \
 285         }                                                               \
 286 } while (0)
 287
 288 #define ASSERTCMP(X, OP, Y)                                             \
 289 do {                                                                    \
 290         if (unlikely(!((X) OP (Y)))) {                                  \
 291                 printk(KERN_ERR "\n");                                  \
 292                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 293                 printk(KERN_ERR "%lx " #OP " %lx is false\n",           \
 294                        (unsigned long)(X), (unsigned long)(Y));         \
 295                 BUG();                                                  \
 296         }                                                               \
 297 } while (0)
 298
 299 #define ASSERTIF(C, X)                                                  \
 300 do {                                                                    \
 301         if (unlikely((C) && !(X))) {                                    \
 302                 printk(KERN_ERR "\n");                                  \
 303                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 304                 BUG();                                                  \
 305         }                                                               \
 306 } while (0)
 307
 308 #define ASSERTIFCMP(C, X, OP, Y)                                        \
 309 do {                                                                    \
 310         if (unlikely((C) && !((X) OP (Y)))) {                           \
 311                 printk(KERN_ERR "\n");                                  \
 312                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 313                 printk(KERN_ERR "%lx " #OP " %lx is false\n",           \
 314                        (unsigned long)(X), (unsigned long)(Y));         \
 315                 BUG();                                                  \
 316         }                                                               \
 317 } while (0)
 318
 319 #else
 320
 321 #define ASSERT(X)                       do {} while (0)
 322 #define ASSERTCMP(X, OP, Y)             do {} while (0)
 323 #define ASSERTIF(C, X)                  do {} while (0)
 324 #define ASSERTIFCMP(C, X, OP, Y)        do {} while (0)
 325
 326 #endif /* assert or not */