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-histogram.c
  32  */
  33 #ifdef CONFIG_FSCACHE_HISTOGRAM
  34 extern atomic_t fscache_obj_instantiate_histogram[HZ];
  35 extern atomic_t fscache_objs_histogram[HZ];
  36 extern atomic_t fscache_ops_histogram[HZ];
  37 extern atomic_t fscache_retrieval_delay_histogram[HZ];
  38 extern atomic_t fscache_retrieval_histogram[HZ];
  39
  40 static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif)
  41 {
  42         unsigned long jif = jiffies - start_jif;
  43         if (jif >= HZ)
  44                 jif = HZ - 1;
  45         atomic_inc(&histogram[jif]);
  46 }
  47
  48 extern const struct file_operations fscache_histogram_fops;
  49
  50 #else
  51 #define fscache_hist(hist, start_jif) do {} while (0)
  52 #endif
  53
  54 /*
  55  * fsc-main.c
  56  */
  57 extern unsigned fscache_defer_lookup;
  58 extern unsigned fscache_defer_create;
  59 extern unsigned fscache_debug;
  60 extern struct kobject *fscache_root;
  61
  62 /*
  63  * fsc-proc.c
  64  */
  65 #ifdef CONFIG_PROC_FS
  66 extern int __init fscache_proc_init(void);
  67 extern void fscache_proc_cleanup(void);
  68 #else
  69 #define fscache_proc_init()     (0)
  70 #define fscache_proc_cleanup()  do {} while (0)
  71 #endif
  72
  73 /*
  74  * fsc-stats.c
  75  */
  76 #ifdef CONFIG_FSCACHE_STATS
  77 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS];
  78 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS];
  79
  80 extern atomic_t fscache_n_op_pend;
  81 extern atomic_t fscache_n_op_run;
  82 extern atomic_t fscache_n_op_enqueue;
  83 extern atomic_t fscache_n_op_deferred_release;
  84 extern atomic_t fscache_n_op_release;
  85 extern atomic_t fscache_n_op_gc;
  86
  87 extern atomic_t fscache_n_attr_changed;
  88 extern atomic_t fscache_n_attr_changed_ok;
  89 extern atomic_t fscache_n_attr_changed_nobufs;
  90 extern atomic_t fscache_n_attr_changed_nomem;
  91 extern atomic_t fscache_n_attr_changed_calls;
  92
  93 extern atomic_t fscache_n_allocs;
  94 extern atomic_t fscache_n_allocs_ok;
  95 extern atomic_t fscache_n_allocs_wait;
  96 extern atomic_t fscache_n_allocs_nobufs;
  97 extern atomic_t fscache_n_alloc_ops;
  98 extern atomic_t fscache_n_alloc_op_waits;
  99
 100 extern atomic_t fscache_n_retrievals;
 101 extern atomic_t fscache_n_retrievals_ok;
 102 extern atomic_t fscache_n_retrievals_wait;
 103 extern atomic_t fscache_n_retrievals_nodata;
 104 extern atomic_t fscache_n_retrievals_nobufs;
 105 extern atomic_t fscache_n_retrievals_intr;
 106 extern atomic_t fscache_n_retrievals_nomem;
 107 extern atomic_t fscache_n_retrieval_ops;
 108 extern atomic_t fscache_n_retrieval_op_waits;
 109
 110 extern atomic_t fscache_n_stores;
 111 extern atomic_t fscache_n_stores_ok;
 112 extern atomic_t fscache_n_stores_again;
 113 extern atomic_t fscache_n_stores_nobufs;
 114 extern atomic_t fscache_n_stores_oom;
 115 extern atomic_t fscache_n_store_ops;
 116 extern atomic_t fscache_n_store_calls;
 117
 118 extern atomic_t fscache_n_marks;
 119 extern atomic_t fscache_n_uncaches;
 120
 121 extern atomic_t fscache_n_acquires;
 122 extern atomic_t fscache_n_acquires_null;
 123 extern atomic_t fscache_n_acquires_no_cache;
 124 extern atomic_t fscache_n_acquires_ok;
 125 extern atomic_t fscache_n_acquires_nobufs;
 126 extern atomic_t fscache_n_acquires_oom;
 127
 128 extern atomic_t fscache_n_updates;
 129 extern atomic_t fscache_n_updates_null;
 130 extern atomic_t fscache_n_updates_run;
 131
 132 extern atomic_t fscache_n_relinquishes;
 133 extern atomic_t fscache_n_relinquishes_null;
 134 extern atomic_t fscache_n_relinquishes_waitcrt;
 135
 136 extern atomic_t fscache_n_cookie_index;
 137 extern atomic_t fscache_n_cookie_data;
 138 extern atomic_t fscache_n_cookie_special;
 139
 140 extern atomic_t fscache_n_object_alloc;
 141 extern atomic_t fscache_n_object_no_alloc;
 142 extern atomic_t fscache_n_object_lookups;
 143 extern atomic_t fscache_n_object_lookups_negative;
 144 extern atomic_t fscache_n_object_lookups_positive;
 145 extern atomic_t fscache_n_object_created;
 146 extern atomic_t fscache_n_object_avail;
 147 extern atomic_t fscache_n_object_dead;
 148
 149 extern atomic_t fscache_n_checkaux_none;
 150 extern atomic_t fscache_n_checkaux_okay;
 151 extern atomic_t fscache_n_checkaux_update;
 152 extern atomic_t fscache_n_checkaux_obsolete;
 153
 154 static inline void fscache_stat(atomic_t *stat)
 155 {
 156         atomic_inc(stat);
 157 }
 158
 159 extern const struct file_operations fscache_stats_fops;
 160 #else
 161
 162 #define fscache_stat(stat) do {} while (0)
 163 #endif
 164
 165 /*****************************************************************************/
 166 /*
 167  * debug tracing
 168  */
 169 #define dbgprintk(FMT, ...) \
 170         printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
 171
 172 /* make sure we maintain the format strings, even when debugging is disabled */
 173 static inline __attribute__((format(printf, 1, 2)))
 174 void _dbprintk(const char *fmt, ...)
 175 {
 176 }
 177
 178 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 179 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 180 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
 181
 182 #define kjournal(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__)
 183
 184 #ifdef __KDEBUG
 185 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
 186 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
 187 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
 188
 189 #elif defined(CONFIG_FSCACHE_DEBUG)
 190 #define _enter(FMT, ...)                        \
 191 do {                                            \
 192         if (__do_kdebug(ENTER))                 \
 193                 kenter(FMT, ##__VA_ARGS__);     \
 194 } while (0)
 195
 196 #define _leave(FMT, ...)                        \
 197 do {                                            \
 198         if (__do_kdebug(LEAVE))                 \
 199                 kleave(FMT, ##__VA_ARGS__);     \
 200 } while (0)
 201
 202 #define _debug(FMT, ...)                        \
 203 do {                                            \
 204         if (__do_kdebug(DEBUG))                 \
 205                 kdebug(FMT, ##__VA_ARGS__);     \
 206 } while (0)
 207
 208 #else
 209 #define _enter(FMT, ...) _dbprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 210 #define _leave(FMT, ...) _dbprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 211 #define _debug(FMT, ...) _dbprintk(FMT, ##__VA_ARGS__)
 212 #endif
 213
 214 /*
 215  * determine whether a particular optional debugging point should be logged
 216  * - we need to go through three steps to persuade cpp to correctly join the
 217  *   shorthand in FSCACHE_DEBUG_LEVEL with its prefix
 218  */
 219 #define ____do_kdebug(LEVEL, POINT) \
 220         unlikely((fscache_debug & \
 221                   (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
 222 #define ___do_kdebug(LEVEL, POINT) \
 223         ____do_kdebug(LEVEL, POINT)
 224 #define __do_kdebug(POINT) \
 225         ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
 226
 227 #define FSCACHE_DEBUG_CACHE     0
 228 #define FSCACHE_DEBUG_COOKIE    1
 229 #define FSCACHE_DEBUG_PAGE      2
 230 #define FSCACHE_DEBUG_OPERATION 3
 231
 232 #define FSCACHE_POINT_ENTER     1
 233 #define FSCACHE_POINT_LEAVE     2
 234 #define FSCACHE_POINT_DEBUG     4
 235
 236 #ifndef FSCACHE_DEBUG_LEVEL
 237 #define FSCACHE_DEBUG_LEVEL CACHE
 238 #endif
 239
 240 /*
 241  * assertions
 242  */
 243 #if 1 /* defined(__KDEBUGALL) */
 244
 245 #define ASSERT(X)                                                       \
 246 do {                                                                    \
 247         if (unlikely(!(X))) {                                           \
 248                 printk(KERN_ERR "\n");                                  \
 249                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 250                 BUG();                                                  \
 251         }                                                               \
 252 } while (0)
 253
 254 #define ASSERTCMP(X, OP, Y)                                             \
 255 do {                                                                    \
 256         if (unlikely(!((X) OP (Y)))) {                                  \
 257                 printk(KERN_ERR "\n");                                  \
 258                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 259                 printk(KERN_ERR "%lx " #OP " %lx is false\n",           \
 260                        (unsigned long)(X), (unsigned long)(Y));         \
 261                 BUG();                                                  \
 262         }                                                               \
 263 } while (0)
 264
 265 #define ASSERTIF(C, X)                                                  \
 266 do {                                                                    \
 267         if (unlikely((C) && !(X))) {                                    \
 268                 printk(KERN_ERR "\n");                                  \
 269                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 270                 BUG();                                                  \
 271         }                                                               \
 272 } while (0)
 273
 274 #define ASSERTIFCMP(C, X, OP, Y)                                        \
 275 do {                                                                    \
 276         if (unlikely((C) && !((X) OP (Y)))) {                           \
 277                 printk(KERN_ERR "\n");                                  \
 278                 printk(KERN_ERR "FS-Cache: Assertion failed\n");        \
 279                 printk(KERN_ERR "%lx " #OP " %lx is false\n",           \
 280                        (unsigned long)(X), (unsigned long)(Y));         \
 281                 BUG();                                                  \
 282         }                                                               \
 283 } while (0)
 284
 285 #else
 286
 287 #define ASSERT(X)                       do {} while (0)
 288 #define ASSERTCMP(X, OP, Y)             do {} while (0)
 289 #define ASSERTIF(C, X)                  do {} while (0)
 290 #define ASSERTIFCMP(C, X, OP, Y)        do {} while (0)
 291
 292 #endif /* assert or not */