[net-next-2.6.git] / fs / fscache / internal.h

/* Internal definitions for FS-Cache
 *
 * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

/*
 * Lock order, in the order in which multiple locks should be obtained:
 * - fscache_addremove_sem
 * - cookie->lock
 * - cookie->parent->lock
 * - cache->object_list_lock
 * - object->lock
 * - object->parent->lock
 * - cookie->stores_lock
 * - fscache_thread_lock
 *
 */

#include <linux/fscache-cache.h>
#include <linux/sched.h>

#define FSCACHE_MIN_THREADS	4
#define FSCACHE_MAX_THREADS	32

/*
 * cache.c
 */
extern struct list_head fscache_cache_list;
extern struct rw_semaphore fscache_addremove_sem;

extern struct fscache_cache *fscache_select_cache_for_object(
	struct fscache_cookie *);

/*
 * cookie.c
 */
extern struct kmem_cache *fscache_cookie_jar;

extern void fscache_cookie_init_once(void *);
extern void __fscache_cookie_put(struct fscache_cookie *);

/*
 * fsdef.c
 */
extern struct fscache_cookie fscache_fsdef_index;
extern struct fscache_cookie_def fscache_fsdef_netfs_def;

/*
 * histogram.c
 */
#ifdef CONFIG_FSCACHE_HISTOGRAM
extern atomic_t fscache_obj_instantiate_histogram[HZ];
extern atomic_t fscache_objs_histogram[HZ];
extern atomic_t fscache_ops_histogram[HZ];
extern atomic_t fscache_retrieval_delay_histogram[HZ];
extern atomic_t fscache_retrieval_histogram[HZ];

static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif)
{
	unsigned long jif = jiffies - start_jif;
	if (jif >= HZ)
		jif = HZ - 1;
	atomic_inc(&histogram[jif]);
}

extern const struct file_operations fscache_histogram_fops;

#else
#define fscache_hist(hist, start_jif) do {} while (0)
#endif

/*
 * main.c
 */
extern unsigned fscache_defer_lookup;
extern unsigned fscache_defer_create;
extern unsigned fscache_debug;
extern struct kobject *fscache_root;
extern struct workqueue_struct *fscache_object_wq;
extern struct workqueue_struct *fscache_op_wq;
DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);

static inline bool fscache_object_congested(void)
{
	return workqueue_congested(WORK_CPU_UNBOUND, fscache_object_wq);
}

extern int fscache_wait_bit(void *);
extern int fscache_wait_bit_interruptible(void *);

/*
 * object.c
 */
extern const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5];

extern void fscache_withdrawing_object(struct fscache_cache *,
				       struct fscache_object *);
extern void fscache_enqueue_object(struct fscache_object *);

/*
 * object-list.c
 */
#ifdef CONFIG_FSCACHE_OBJECT_LIST
extern const struct file_operations fscache_objlist_fops;

extern void fscache_objlist_add(struct fscache_object *);
#else
#define fscache_objlist_add(object) do {} while(0)
#endif

/*
 * operation.c
 */
extern int fscache_submit_exclusive_op(struct fscache_object *,
				       struct fscache_operation *);
extern int fscache_submit_op(struct fscache_object *,
			     struct fscache_operation *);
extern int fscache_cancel_op(struct fscache_operation *);
extern void fscache_abort_object(struct fscache_object *);
extern void fscache_start_operations(struct fscache_object *);
extern void fscache_operation_gc(struct work_struct *);

/*
 * proc.c
 */
#ifdef CONFIG_PROC_FS
extern int __init fscache_proc_init(void);
extern void fscache_proc_cleanup(void);
#else
#define fscache_proc_init()	(0)
#define fscache_proc_cleanup()	do {} while (0)
#endif

/*
 * stats.c
 */
#ifdef CONFIG_FSCACHE_STATS
extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS];
extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS];

extern atomic_t fscache_n_op_pend;
extern atomic_t fscache_n_op_run;
extern atomic_t fscache_n_op_enqueue;
extern atomic_t fscache_n_op_deferred_release;
extern atomic_t fscache_n_op_release;
extern atomic_t fscache_n_op_gc;
extern atomic_t fscache_n_op_cancelled;
extern atomic_t fscache_n_op_rejected;

extern atomic_t fscache_n_attr_changed;
extern atomic_t fscache_n_attr_changed_ok;
extern atomic_t fscache_n_attr_changed_nobufs;
extern atomic_t fscache_n_attr_changed_nomem;
extern atomic_t fscache_n_attr_changed_calls;

extern atomic_t fscache_n_allocs;
extern atomic_t fscache_n_allocs_ok;
extern atomic_t fscache_n_allocs_wait;
extern atomic_t fscache_n_allocs_nobufs;
extern atomic_t fscache_n_allocs_intr;
extern atomic_t fscache_n_allocs_object_dead;
extern atomic_t fscache_n_alloc_ops;
extern atomic_t fscache_n_alloc_op_waits;

extern atomic_t fscache_n_retrievals;
extern atomic_t fscache_n_retrievals_ok;
extern atomic_t fscache_n_retrievals_wait;
extern atomic_t fscache_n_retrievals_nodata;
extern atomic_t fscache_n_retrievals_nobufs;
extern atomic_t fscache_n_retrievals_intr;
extern atomic_t fscache_n_retrievals_nomem;
extern atomic_t fscache_n_retrievals_object_dead;
extern atomic_t fscache_n_retrieval_ops;
extern atomic_t fscache_n_retrieval_op_waits;

extern atomic_t fscache_n_stores;
extern atomic_t fscache_n_stores_ok;
extern atomic_t fscache_n_stores_again;
extern atomic_t fscache_n_stores_nobufs;
extern atomic_t fscache_n_stores_oom;
extern atomic_t fscache_n_store_ops;
extern atomic_t fscache_n_store_calls;
extern atomic_t fscache_n_store_pages;
extern atomic_t fscache_n_store_radix_deletes;
extern atomic_t fscache_n_store_pages_over_limit;

extern atomic_t fscache_n_store_vmscan_not_storing;
extern atomic_t fscache_n_store_vmscan_gone;
extern atomic_t fscache_n_store_vmscan_busy;
extern atomic_t fscache_n_store_vmscan_cancelled;

extern atomic_t fscache_n_marks;
extern atomic_t fscache_n_uncaches;

extern atomic_t fscache_n_acquires;
extern atomic_t fscache_n_acquires_null;
extern atomic_t fscache_n_acquires_no_cache;
extern atomic_t fscache_n_acquires_ok;
extern atomic_t fscache_n_acquires_nobufs;
extern atomic_t fscache_n_acquires_oom;

extern atomic_t fscache_n_updates;
extern atomic_t fscache_n_updates_null;
extern atomic_t fscache_n_updates_run;

extern atomic_t fscache_n_relinquishes;
extern atomic_t fscache_n_relinquishes_null;
extern atomic_t fscache_n_relinquishes_waitcrt;
extern atomic_t fscache_n_relinquishes_retire;

extern atomic_t fscache_n_cookie_index;
extern atomic_t fscache_n_cookie_data;
extern atomic_t fscache_n_cookie_special;

extern atomic_t fscache_n_object_alloc;
extern atomic_t fscache_n_object_no_alloc;
extern atomic_t fscache_n_object_lookups;
extern atomic_t fscache_n_object_lookups_negative;
extern atomic_t fscache_n_object_lookups_positive;
extern atomic_t fscache_n_object_lookups_timed_out;
extern atomic_t fscache_n_object_created;
extern atomic_t fscache_n_object_avail;
extern atomic_t fscache_n_object_dead;

extern atomic_t fscache_n_checkaux_none;
extern atomic_t fscache_n_checkaux_okay;
extern atomic_t fscache_n_checkaux_update;
extern atomic_t fscache_n_checkaux_obsolete;

extern atomic_t fscache_n_cop_alloc_object;
extern atomic_t fscache_n_cop_lookup_object;
extern atomic_t fscache_n_cop_lookup_complete;
extern atomic_t fscache_n_cop_grab_object;
extern atomic_t fscache_n_cop_update_object;
extern atomic_t fscache_n_cop_drop_object;
extern atomic_t fscache_n_cop_put_object;
extern atomic_t fscache_n_cop_sync_cache;
extern atomic_t fscache_n_cop_attr_changed;
extern atomic_t fscache_n_cop_read_or_alloc_page;
extern atomic_t fscache_n_cop_read_or_alloc_pages;
extern atomic_t fscache_n_cop_allocate_page;
extern atomic_t fscache_n_cop_allocate_pages;
extern atomic_t fscache_n_cop_write_page;
extern atomic_t fscache_n_cop_uncache_page;
extern atomic_t fscache_n_cop_dissociate_pages;

static inline void fscache_stat(atomic_t *stat)
{
	atomic_inc(stat);
}

static inline void fscache_stat_d(atomic_t *stat)
{
	atomic_dec(stat);
}

#define __fscache_stat(stat) (stat)

extern const struct file_operations fscache_stats_fops;
#else

#define __fscache_stat(stat) (NULL)
#define fscache_stat(stat) do {} while (0)
#define fscache_stat_d(stat) do {} while (0)
#endif

/*
 * raise an event on an object
 * - if the event is not masked for that object, then the object is
 *   queued for attention by the thread pool.
 */
static inline void fscache_raise_event(struct fscache_object *object,
				       unsigned event)
{
	if (!test_and_set_bit(event, &object->events) &&
	    test_bit(event, &object->event_mask))
		fscache_enqueue_object(object);
}

/*
 * drop a reference to a cookie
 */
static inline void fscache_cookie_put(struct fscache_cookie *cookie)
{
	BUG_ON(atomic_read(&cookie->usage) <= 0);
	if (atomic_dec_and_test(&cookie->usage))
		__fscache_cookie_put(cookie);
}

/*
 * get an extra reference to a netfs retrieval context
 */
static inline
void *fscache_get_context(struct fscache_cookie *cookie, void *context)
{
	if (cookie->def->get_context)
		cookie->def->get_context(cookie->netfs_data, context);
	return context;
}

/*
 * release a reference to a netfs retrieval context
 */
static inline
void fscache_put_context(struct fscache_cookie *cookie, void *context)
{
	if (cookie->def->put_context)
		cookie->def->put_context(cookie->netfs_data, context);
}

/*****************************************************************************/
/*
 * debug tracing
 */
#define dbgprintk(FMT, ...) \
	printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)

#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)

#define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)

#ifdef __KDEBUG
#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)

#elif defined(CONFIG_FSCACHE_DEBUG)
#define _enter(FMT, ...)			\
do {						\
	if (__do_kdebug(ENTER))			\
		kenter(FMT, ##__VA_ARGS__);	\
} while (0)

#define _leave(FMT, ...)			\
do {						\
	if (__do_kdebug(LEAVE))			\
		kleave(FMT, ##__VA_ARGS__);	\
} while (0)

#define _debug(FMT, ...)			\
do {						\
	if (__do_kdebug(DEBUG))			\
		kdebug(FMT, ##__VA_ARGS__);	\
} while (0)

#else
#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
#endif

/*
 * determine whether a particular optional debugging point should be logged
 * - we need to go through three steps to persuade cpp to correctly join the
 *   shorthand in FSCACHE_DEBUG_LEVEL with its prefix
 */
#define ____do_kdebug(LEVEL, POINT) \
	unlikely((fscache_debug & \
		  (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
#define ___do_kdebug(LEVEL, POINT) \
	____do_kdebug(LEVEL, POINT)
#define __do_kdebug(POINT) \
	___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)

#define FSCACHE_DEBUG_CACHE	0
#define FSCACHE_DEBUG_COOKIE	1
#define FSCACHE_DEBUG_PAGE	2
#define FSCACHE_DEBUG_OPERATION	3

#define FSCACHE_POINT_ENTER	1
#define FSCACHE_POINT_LEAVE	2
#define FSCACHE_POINT_DEBUG	4

#ifndef FSCACHE_DEBUG_LEVEL
#define FSCACHE_DEBUG_LEVEL CACHE
#endif

/*
 * assertions
 */
#if 1 /* defined(__KDEBUGALL) */

#define ASSERT(X)							\
do {									\
	if (unlikely(!(X))) {						\
		printk(KERN_ERR "\n");					\
		printk(KERN_ERR "FS-Cache: Assertion failed\n");	\
		BUG();							\
	}								\
} while (0)

#define ASSERTCMP(X, OP, Y)						\
do {									\
	if (unlikely(!((X) OP (Y)))) {					\
		printk(KERN_ERR "\n");					\
		printk(KERN_ERR "FS-Cache: Assertion failed\n");	\
		printk(KERN_ERR "%lx " #OP " %lx is false\n",		\
		       (unsigned long)(X), (unsigned long)(Y));		\
		BUG();							\
	}								\
} while (0)

#define ASSERTIF(C, X)							\
do {									\
	if (unlikely((C) && !(X))) {					\
		printk(KERN_ERR "\n");					\
		printk(KERN_ERR "FS-Cache: Assertion failed\n");	\
		BUG();							\
	}								\
} while (0)

#define ASSERTIFCMP(C, X, OP, Y)					\
do {									\
	if (unlikely((C) && !((X) OP (Y)))) {				\
		printk(KERN_ERR "\n");					\
		printk(KERN_ERR "FS-Cache: Assertion failed\n");	\
		printk(KERN_ERR "%lx " #OP " %lx is false\n",		\
		       (unsigned long)(X), (unsigned long)(Y));		\
		BUG();							\
	}								\
} while (0)

#else

#define ASSERT(X)			do {} while (0)
#define ASSERTCMP(X, OP, Y)		do {} while (0)
#define ASSERTIF(C, X)			do {} while (0)
#define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)

#endif /* assert or not */
Commit	Line	Data
06b3db1b DH	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
1bccf513	20	* - cookie->stores_lock
06b3db1b DH	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
0e04d4ce	31	/*
348ca102	32	* cache.c
0e04d4ce DH	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
955d0091	40	/*
348ca102	41	* cookie.c
955d0091 DH	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
a6891645	48	/*
348ca102	49	* fsdef.c
a6891645 DH	50	*/
	51	extern struct fscache_cookie fscache_fsdef_index;
	52	extern struct fscache_cookie_def fscache_fsdef_netfs_def;
	53
7394daa8	54	/*
348ca102	55	* histogram.c
7394daa8 DH	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
06b3db1b	78	/*
348ca102	79	* main.c
06b3db1b DH	80	*/
	81	extern unsigned fscache_defer_lookup;
	82	extern unsigned fscache_defer_create;
	83	extern unsigned fscache_debug;
	84	extern struct kobject *fscache_root;
8b8edefa	85	extern struct workqueue_struct *fscache_object_wq;
8af7c124	86	extern struct workqueue_struct *fscache_op_wq;
8b8edefa TH	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	}
06b3db1b	93
2868cbea DH	94	extern int fscache_wait_bit(void *);
	95	extern int fscache_wait_bit_interruptible(void *);
	96
36c95590	97	/*
348ca102	98	* object.c
36c95590	99	*/
4fbf4291 DH	100	extern const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5];
4fbf4291 DH	101
36c95590 DH	102	extern void fscache_withdrawing_object(struct fscache_cache *,
	103	struct fscache_object *);
	104	extern void fscache_enqueue_object(struct fscache_object *);
	105
4fbf4291 DH	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
36c95590	117	/*
348ca102	118	* operation.c
36c95590	119	*/
952efe7b DH	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 *);
5753c441	124	extern int fscache_cancel_op(struct fscache_operation *);
952efe7b DH	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 *);
36c95590	128
7394daa8	129	/*
348ca102	130	* proc.c
7394daa8 DH	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	/*
348ca102	141	* stats.c
7394daa8 DH	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;
5753c441	153	extern atomic_t fscache_n_op_cancelled;
e3d4d28b	154	extern atomic_t fscache_n_op_rejected;
7394daa8 DH	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;
5753c441	166	extern atomic_t fscache_n_allocs_intr;
60d543ca	167	extern atomic_t fscache_n_allocs_object_dead;
7394daa8 DH	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;
60d543ca	178	extern atomic_t fscache_n_retrievals_object_dead;
7394daa8 DH	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;
1bccf513 DH	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;
7394daa8	192
201a1542 DH	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
7394daa8 DH	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;
2175bb06	215	extern atomic_t fscache_n_relinquishes_retire;
7394daa8 DH	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;
fee096de	226	extern atomic_t fscache_n_object_lookups_timed_out;
7394daa8 DH	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
52bd75fd DH	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
7394daa8 DH	253	static inline void fscache_stat(atomic_t *stat)
	254	{
	255	atomic_inc(stat);
	256	}
	257
52bd75fd DH	258	static inline void fscache_stat_d(atomic_t *stat)
	259	{
	260	atomic_dec(stat);
	261	}
	262
60d543ca DH	263	#define __fscache_stat(stat) (stat)
60d543ca DH	264
7394daa8 DH	265	extern const struct file_operations fscache_stats_fops;
	266	#else
	267
60d543ca	268	#define __fscache_stat(stat) (NULL)
7394daa8	269	#define fscache_stat(stat) do {} while (0)
4fa9f4ed	270	#define fscache_stat_d(stat) do {} while (0)
7394daa8 DH	271	#endif
7394daa8 DH	272
0e04d4ce DH	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	{
36c95590 DH	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);
0e04d4ce DH	294	}
0e04d4ce DH	295
b5108822 DH	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
06b3db1b DH	317	/*****************************************************************************/
	318	/*
	319	* debug tracing
	320	*/
	321	#define dbgprintk(FMT, ...) \
	322	printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
	323
06b3db1b DH	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
12fdff3f	328	#define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
06b3db1b DH	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
12fdff3f DH	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__)
06b3db1b DH	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 */