ref_tracker.h

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2#ifndef _LINUX_REF_TRACKER_H
  3#define _LINUX_REF_TRACKER_H
  4#include <linux/refcount.h>
  5#include <linux/types.h>
  6#include <linux/spinlock.h>
  7#include <linux/stackdepot.h>
  8
  9#define __ostream_printf __printf(2, 3)
 10
 11struct ref_tracker;
 12
 13struct ref_tracker_dir {
 14#ifdef CONFIG_REF_TRACKER
 15	spinlock_t		lock;
 16	unsigned int		quarantine_avail;
 17	refcount_t		untracked;
 18	refcount_t		no_tracker;
 19	bool			dead;
 20	struct list_head	list; /* List of active trackers */
 21	struct list_head	quarantine; /* List of dead trackers */
 22	const char		*class; /* object classname */
 23#endif
 24};
 25
 26#ifdef CONFIG_REF_TRACKER
 27
 28#ifdef CONFIG_DEBUG_FS
 29
 30void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir);
 31void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...);
 32
 33#else /* CONFIG_DEBUG_FS */
 34
 35static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir)
 36{
 37}
 38
 39static inline __ostream_printf
 40void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...)
 41{
 42}
 43
 44#endif /* CONFIG_DEBUG_FS */
 45
 46/**
 47 * ref_tracker_dir_init - initialize a ref_tracker dir
 48 * @dir: ref_tracker_dir to be initialized
 49 * @quarantine_count: max number of entries to be tracked
 50 * @class: pointer to static string that describes object type
 51 *
 52 * Initialize a ref_tracker_dir. If debugfs is configured, then a file
 53 * will also be created for it under the top-level ref_tracker debugfs
 54 * directory.
 55 *
 56 * Note that @class must point to a static string.
 57 */
 58static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir,
 59					unsigned int quarantine_count,
 60					const char *class)
 61{
 62	INIT_LIST_HEAD(&dir->list);
 63	INIT_LIST_HEAD(&dir->quarantine);
 64	spin_lock_init(&dir->lock);
 65	dir->quarantine_avail = quarantine_count;
 66	dir->dead = false;
 67	refcount_set(&dir->untracked, 1);
 68	refcount_set(&dir->no_tracker, 1);
 69	dir->class = class;
 70	ref_tracker_dir_debugfs(dir);
 71	stack_depot_init();
 72}
 73
 74void ref_tracker_dir_exit(struct ref_tracker_dir *dir);
 75
 76void ref_tracker_dir_print_locked(struct ref_tracker_dir *dir,
 77				  unsigned int display_limit);
 78
 79void ref_tracker_dir_print(struct ref_tracker_dir *dir,
 80			   unsigned int display_limit);
 81
 82int ref_tracker_dir_snprint(struct ref_tracker_dir *dir, char *buf, size_t size);
 83
 84int ref_tracker_alloc(struct ref_tracker_dir *dir,
 85		      struct ref_tracker **trackerp, gfp_t gfp);
 86
 87int ref_tracker_free(struct ref_tracker_dir *dir,
 88		     struct ref_tracker **trackerp);
 89
 90#else /* CONFIG_REF_TRACKER */
 91
 92static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir,
 93					unsigned int quarantine_count,
 94					const char *class)
 95{
 96}
 97
 98static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir)
 99{
100}
101
102static inline __ostream_printf
103void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...)
104{
105}
106
107static inline void ref_tracker_dir_exit(struct ref_tracker_dir *dir)
108{
109}
110
111static inline void ref_tracker_dir_print_locked(struct ref_tracker_dir *dir,
112						unsigned int display_limit)
113{
114}
115
116static inline void ref_tracker_dir_print(struct ref_tracker_dir *dir,
117					 unsigned int display_limit)
118{
119}
120
121static inline int ref_tracker_dir_snprint(struct ref_tracker_dir *dir,
122					  char *buf, size_t size)
123{
124	return 0;
125}
126
127static inline int ref_tracker_alloc(struct ref_tracker_dir *dir,
128				    struct ref_tracker **trackerp,
129				    gfp_t gfp)
130{
131	return 0;
132}
133
134static inline int ref_tracker_free(struct ref_tracker_dir *dir,
135				   struct ref_tracker **trackerp)
136{
137	return 0;
138}
139
140#endif
141
142#endif /* _LINUX_REF_TRACKER_H */