timer: implement lockdep deadlock detection

This modifies the timer code in a way to allow lockdep to detect
deadlocks resulting from a lock being taken in the timer function
as well as around the del_timer_sync() call.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
This commit is contained in:
Johannes Berg 2009-01-29 16:03:20 +01:00 committed by Ingo Molnar
parent 673f820591
commit 6f2b9b9a9d
2 changed files with 141 additions and 20 deletions

View file

@ -5,6 +5,7 @@
#include <linux/ktime.h>
#include <linux/stddef.h>
#include <linux/debugobjects.h>
#include <linux/stringify.h>
struct tvec_base;
@ -21,52 +22,126 @@ struct timer_list {
char start_comm[16];
int start_pid;
#endif
#ifdef CONFIG_LOCKDEP
struct lockdep_map lockdep_map;
#endif
};
extern struct tvec_base boot_tvec_bases;
#ifdef CONFIG_LOCKDEP
/*
* NB: because we have to copy the lockdep_map, setting the lockdep_map key
* (second argument) here is required, otherwise it could be initialised to
* the copy of the lockdep_map later! We use the pointer to and the string
* "<file>:<line>" as the key resp. the name of the lockdep_map.
*/
#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn) \
.lockdep_map = STATIC_LOCKDEP_MAP_INIT(_kn, &_kn),
#else
#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
#endif
#define TIMER_INITIALIZER(_function, _expires, _data) { \
.entry = { .prev = TIMER_ENTRY_STATIC }, \
.function = (_function), \
.expires = (_expires), \
.data = (_data), \
.base = &boot_tvec_bases, \
__TIMER_LOCKDEP_MAP_INITIALIZER( \
__FILE__ ":" __stringify(__LINE__)) \
}
#define DEFINE_TIMER(_name, _function, _expires, _data) \
struct timer_list _name = \
TIMER_INITIALIZER(_function, _expires, _data)
void init_timer(struct timer_list *timer);
void init_timer_deferrable(struct timer_list *timer);
void init_timer_key(struct timer_list *timer,
const char *name,
struct lock_class_key *key);
void init_timer_deferrable_key(struct timer_list *timer,
const char *name,
struct lock_class_key *key);
#ifdef CONFIG_LOCKDEP
#define init_timer(timer) \
do { \
static struct lock_class_key __key; \
init_timer_key((timer), #timer, &__key); \
} while (0)
#define init_timer_deferrable(timer) \
do { \
static struct lock_class_key __key; \
init_timer_deferrable_key((timer), #timer, &__key); \
} while (0)
#define init_timer_on_stack(timer) \
do { \
static struct lock_class_key __key; \
init_timer_on_stack_key((timer), #timer, &__key); \
} while (0)
#define setup_timer(timer, fn, data) \
do { \
static struct lock_class_key __key; \
setup_timer_key((timer), #timer, &__key, (fn), (data));\
} while (0)
#define setup_timer_on_stack(timer, fn, data) \
do { \
static struct lock_class_key __key; \
setup_timer_on_stack_key((timer), #timer, &__key, \
(fn), (data)); \
} while (0)
#else
#define init_timer(timer)\
init_timer_key((timer), NULL, NULL)
#define init_timer_deferrable(timer)\
init_timer_deferrable_key((timer), NULL, NULL)
#define init_timer_on_stack(timer)\
init_timer_on_stack_key((timer), NULL, NULL)
#define setup_timer(timer, fn, data)\
setup_timer_key((timer), NULL, NULL, (fn), (data))
#define setup_timer_on_stack(timer, fn, data)\
setup_timer_on_stack_key((timer), NULL, NULL, (fn), (data))
#endif
#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
extern void init_timer_on_stack(struct timer_list *timer);
extern void init_timer_on_stack_key(struct timer_list *timer,
const char *name,
struct lock_class_key *key);
extern void destroy_timer_on_stack(struct timer_list *timer);
#else
static inline void destroy_timer_on_stack(struct timer_list *timer) { }
static inline void init_timer_on_stack(struct timer_list *timer)
static inline void init_timer_on_stack_key(struct timer_list *timer,
const char *name,
struct lock_class_key *key)
{
init_timer(timer);
init_timer_key(timer, name, key);
}
#endif
static inline void setup_timer(struct timer_list * timer,
static inline void setup_timer_key(struct timer_list * timer,
const char *name,
struct lock_class_key *key,
void (*function)(unsigned long),
unsigned long data)
{
timer->function = function;
timer->data = data;
init_timer(timer);
init_timer_key(timer, name, key);
}
static inline void setup_timer_on_stack(struct timer_list *timer,
static inline void setup_timer_on_stack_key(struct timer_list *timer,
const char *name,
struct lock_class_key *key,
void (*function)(unsigned long),
unsigned long data)
{
timer->function = function;
timer->data = data;
init_timer_on_stack(timer);
init_timer_on_stack_key(timer, name, key);
}
/**