/* 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 * - fscache_thread_lock * */ #include <linux/fscache-cache.h> #include <linux/sched.h> #define FSCACHE_MIN_THREADS 4 #define FSCACHE_MAX_THREADS 32 /* * fsc-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 *); /* * fsc-cookie.c */ extern struct kmem_cache *fscache_cookie_jar; extern void fscache_cookie_init_once(void *); extern void __fscache_cookie_put(struct fscache_cookie *); /* * fsc-fsdef.c */ extern struct fscache_cookie fscache_fsdef_index; extern struct fscache_cookie_def fscache_fsdef_netfs_def; /* * fsc-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 /* * fsc-main.c */ extern unsigned fscache_defer_lookup; extern unsigned fscache_defer_create; extern unsigned fscache_debug; extern struct kobject *fscache_root; extern int fscache_wait_bit(void *); extern int fscache_wait_bit_interruptible(void *); /* * fsc-object.c */ extern void fscache_withdrawing_object(struct fscache_cache *, struct fscache_object *); extern void fscache_enqueue_object(struct fscache_object *); /* * fsc-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 void fscache_abort_object(struct fscache_object *); extern void fscache_start_operations(struct fscache_object *); extern void fscache_operation_gc(struct work_struct *); /* * fsc-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 /* * fsc-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_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_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_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_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_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_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; static inline void fscache_stat(atomic_t *stat) { atomic_inc(stat); } extern const struct file_operations fscache_stats_fops; #else #define fscache_stat(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__) /* make sure we maintain the format strings, even when debugging is disabled */ static inline __attribute__((format(printf, 1, 2))) void _dbprintk(const char *fmt, ...) { } #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, ...) _dbprintk(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, ...) _dbprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) #define _leave(FMT, ...) _dbprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) #define _debug(FMT, ...) _dbprintk(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 */