debugobjects.c

/*
 * Generic infrastructure for lifetime debugging of objects.
 *
 * Started by Thomas Gleixner
 *
 * Copyright (C) 2008, Thomas Gleixner <tglx@linutronix.de>
 *
 * For licencing details see kernel-base/COPYING
 */
#include <linux/debugobjects.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/hash.h>

#define ODEBUG_HASH_BITS	14
#define ODEBUG_HASH_SIZE	(1 << ODEBUG_HASH_BITS)

#define ODEBUG_POOL_SIZE	512
#define ODEBUG_POOL_MIN_LEVEL	256

#define ODEBUG_CHUNK_SHIFT	PAGE_SHIFT
#define ODEBUG_CHUNK_SIZE	(1 << ODEBUG_CHUNK_SHIFT)
#define ODEBUG_CHUNK_MASK	(~(ODEBUG_CHUNK_SIZE - 1))

struct debug_bucket {
	struct hlist_head	list;
	raw_spinlock_t		lock;
};

static struct debug_bucket	obj_hash[ODEBUG_HASH_SIZE];

static struct debug_obj		obj_static_pool[ODEBUG_POOL_SIZE] __initdata;

static DEFINE_RAW_SPINLOCK(pool_lock);

static HLIST_HEAD(obj_pool);

static int			obj_pool_min_free = ODEBUG_POOL_SIZE;
static int			obj_pool_free = ODEBUG_POOL_SIZE;
static int			obj_pool_used;
static int			obj_pool_max_used;
static struct kmem_cache	*obj_cache;

static int			debug_objects_maxchain __read_mostly;
static int			debug_objects_fixups __read_mostly;
static int			debug_objects_warnings __read_mostly;
static int			debug_objects_enabled __read_mostly
				= CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT;

static struct debug_obj_descr	*descr_test  __read_mostly;

static void free_obj_work(struct work_struct *work);
static DECLARE_WORK(debug_obj_work, free_obj_work);

static int __init enable_object_debug(char *str)
{
	debug_objects_enabled = 1;
	return 0;
}

static int __init disable_object_debug(char *str)
{
	debug_objects_enabled = 0;
	return 0;
}

early_param("debug_objects", enable_object_debug);