diff options
| -rw-r--r-- | drivers/parport/ieee1284.c | 4 | ||||
| -rw-r--r-- | fs/aio.c | 5 | ||||
| -rw-r--r-- | include/linux/poison.h | 7 | ||||
| -rw-r--r-- | include/linux/timer.h | 23 | ||||
| -rw-r--r-- | kernel/timer.c | 153 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 8 |
6 files changed, 187 insertions, 13 deletions
diff --git a/drivers/parport/ieee1284.c b/drivers/parport/ieee1284.c index 54a6ef7..0338b09 100644 --- a/drivers/parport/ieee1284.c +++ b/drivers/parport/ieee1284.c @@ -76,7 +76,7 @@ int parport_wait_event (struct parport *port, signed long timeout) semaphore. */ return 1; - init_timer (&timer); + init_timer_on_stack(&timer); timer.expires = jiffies + timeout; timer.function = timeout_waiting_on_port; port_from_cookie[port->number % PARPORT_MAX] = port; @@ -88,6 +88,8 @@ int parport_wait_event (struct parport *port, signed long timeout) /* Timed out. */ ret = 1; + destroy_timer_on_stack(&timer); + return ret; } @@ -1078,9 +1078,7 @@ static void timeout_func(unsigned long data) static inline void init_timeout(struct aio_timeout *to) { - init_timer(&to->timer); - to->timer.data = (unsigned long)to; - to->timer.function = timeout_func; + setup_timer_on_stack(&to->timer, timeout_func, (unsigned long) to); to->timed_out = 0; to->p = current; } @@ -1213,6 +1211,7 @@ retry: if (timeout) clear_timeout(&to); out: + destroy_timer_on_stack(&to.timer); return i ? i : ret; } diff --git a/include/linux/poison.h b/include/linux/poison.h index a9c31be..9f31683 100644 --- a/include/linux/poison.h +++ b/include/linux/poison.h @@ -10,6 +10,13 @@ #define LIST_POISON1 ((void *) 0x00100100) #define LIST_POISON2 ((void *) 0x00200200) +/********** include/linux/timer.h **********/ +/* + * Magic number "tsta" to indicate a static timer initializer + * for the object debugging code. + */ +#define TIMER_ENTRY_STATIC ((void *) 0x74737461) + /********** mm/slab.c **********/ /* * Magic nums for obj red zoning. diff --git a/include/linux/timer.h b/include/linux/timer.h index 979fefd..d4ba792 100644 --- a/include/linux/timer.h +++ b/include/linux/timer.h @@ -4,6 +4,7 @@ #include <linux/list.h> #include <linux/ktime.h> #include <linux/stddef.h> +#include <linux/debugobjects.h> struct tvec_base; @@ -25,6 +26,7 @@ struct timer_list { extern struct tvec_base boot_tvec_bases; #define TIMER_INITIALIZER(_function, _expires, _data) { \ + .entry = { .prev = TIMER_ENTRY_STATIC }, \ .function = (_function), \ .expires = (_expires), \ .data = (_data), \ @@ -38,6 +40,17 @@ extern struct tvec_base boot_tvec_bases; void init_timer(struct timer_list *timer); void init_timer_deferrable(struct timer_list *timer); +#ifdef CONFIG_DEBUG_OBJECTS_TIMERS +extern void init_timer_on_stack(struct timer_list *timer); +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) +{ + init_timer(timer); +} +#endif + static inline void setup_timer(struct timer_list * timer, void (*function)(unsigned long), unsigned long data) @@ -47,6 +60,15 @@ static inline void setup_timer(struct timer_list * timer, init_timer(timer); } +static inline void setup_timer_on_stack(struct timer_list *timer, + void (*function)(unsigned long), + unsigned long data) +{ + timer->function = function; + timer->data = data; + init_timer_on_stack(timer); +} + /** * timer_pending - is a timer pending? * @timer: the timer in question @@ -164,5 +186,4 @@ unsigned long __round_jiffies_relative(unsigned long j, int cpu); unsigned long round_jiffies(unsigned long j); unsigned long round_jiffies_relative(unsigned long j); - #endif diff --git a/kernel/timer.c b/kernel/timer.c index f3d35d4..ceacc66 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -320,14 +320,130 @@ static void timer_stats_account_timer(struct timer_list *timer) static void timer_stats_account_timer(struct timer_list *timer) {} #endif -/** - * init_timer - initialize a timer. - * @timer: the timer to be initialized - * - * init_timer() must be done to a timer prior calling *any* of the - * other timer functions. +#ifdef CONFIG_DEBUG_OBJECTS_TIMERS + +static struct debug_obj_descr timer_debug_descr; + +/* + * fixup_init is called when: + * - an active object is initialized */ -void init_timer(struct timer_list *timer) +static int timer_fixup_init(void *addr, enum debug_obj_state state) +{ + struct timer_list *timer = addr; + + switch (state) { + case ODEBUG_STATE_ACTIVE: + del_timer_sync(timer); + debug_object_init(timer, &timer_debug_descr); + return 1; + default: + return 0; + } +} + +/* + * fixup_activate is called when: + * - an active object is activated + * - an unknown object is activated (might be a statically initialized object) + */ +static int timer_fixup_activate(void *addr, enum debug_obj_state state) +{ + struct timer_list *timer = addr; + + switch (state) { + + case ODEBUG_STATE_NOTAVAILABLE: + /* + * This is not really a fixup. The timer was + * statically initialized. We just make sure that it + * is tracked in the object tracker. + */ + if (timer->entry.next == NULL && + timer->entry.prev == TIMER_ENTRY_STATIC) { + debug_object_init(timer, &timer_debug_descr); + debug_object_activate(timer, &timer_debug_descr); + return 0; + } else { + WARN_ON_ONCE(1); + } + return 0; + + case ODEBUG_STATE_ACTIVE: + WARN_ON(1); + + default: + return 0; + } +} + +/* + * fixup_free is called when: + * - an active object is freed + */ +static int timer_fixup_free(void *addr, enum debug_obj_state state) +{ + struct timer_list *timer = addr; + + switch (state) { + case ODEBUG_STATE_ACTIVE: + del_timer_sync(timer); + debug_object_free(timer, &timer_debug_descr); + return 1; + default: + return 0; + } +} + +static struct debug_obj_descr timer_debug_descr = { + .name = "timer_list", + .fixup_init = timer_fixup_init, + .fixup_activate = timer_fixup_activate, + .fixup_free = timer_fixup_free, +}; + +static inline void debug_timer_init(struct timer_list *timer) +{ + debug_object_init(timer, &timer_debug_descr); +} + +static inline void debug_timer_activate(struct timer_list *timer) +{ + debug_object_activate(timer, &timer_debug_descr); +} + +static inline void debug_timer_deactivate(struct timer_list *timer) +{ + debug_object_deactivate(timer, &timer_debug_descr); +} + +static inline void debug_timer_free(struct timer_list *timer) +{ + debug_object_free(timer, &timer_debug_descr); +} + +static void __init_timer(struct timer_list *timer); + +void init_timer_on_stack(struct timer_list *timer) +{ + debug_object_init_on_stack(timer, &timer_debug_descr); + __init_timer(timer); +} +EXPORT_SYMBOL_GPL(init_timer_on_stack); + +void destroy_timer_on_stack(struct timer_list *timer) +{ + debug_object_free(timer, &timer_debug_descr); +} +EXPORT_SYMBOL_GPL(destroy_timer_on_stack); + +#else +static inline void debug_timer_init(struct timer_list *timer) { } +static inline void debug_timer_activate(struct timer_list *timer) { } +static inline void debug_timer_deactivate(struct timer_list *timer) { } +#endif + +static void __init_timer(struct timer_list *timer) { timer->entry.next = NULL; timer->base = __raw_get_cpu_var(tvec_bases); @@ -337,6 +453,19 @@ void init_timer(struct timer_list *timer) memset(timer->start_comm, 0, TASK_COMM_LEN); #endif } + +/** + * init_timer - initialize a timer. + * @timer: the timer to be initialized + * + * init_timer() must be done to a timer prior calling *any* of the + * other timer functions. + */ +void init_timer(struct timer_list *timer) +{ + debug_timer_init(timer); + __init_timer(timer); +} EXPORT_SYMBOL(init_timer); void init_timer_deferrable(struct timer_list *timer) @@ -351,6 +480,8 @@ static inline void detach_timer(struct timer_list *timer, { struct list_head *entry = &timer->entry; + debug_timer_deactivate(timer); + __list_del(entry->prev, entry->next); if (clear_pending) entry->next = NULL; @@ -405,6 +536,8 @@ int __mod_timer(struct timer_list *timer, unsigned long expires) ret = 1; } + debug_timer_activate(timer); + new_base = __get_cpu_var(tvec_bases); if (base != new_base) { @@ -450,6 +583,7 @@ void add_timer_on(struct timer_list *timer, int cpu) BUG_ON(timer_pending(timer) || !timer->function); spin_lock_irqsave(&base->lock, flags); timer_set_base(timer, base); + debug_timer_activate(timer); internal_add_timer(base, timer); /* * Check whether the other CPU is idle and needs to be @@ -1086,11 +1220,14 @@ signed long __sched schedule_timeout(signed long timeout) expire = timeout + jiffies; - setup_timer(&timer, process_timeout, (unsigned long)current); + setup_timer_on_stack(&timer, process_timeout, (unsigned long)current); __mod_timer(&timer, expire); schedule(); del_singleshot_timer_sync(&timer); + /* Remove the timer from the object tracker */ + destroy_timer_on_stack(&timer); + timeout = expire - jiffies; out: diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 3e132b0..d2099f4 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -217,6 +217,14 @@ config DEBUG_OBJECTS_FREE properly. This can make kmalloc/kfree-intensive workloads much slower. +config DEBUG_OBJECTS_TIMERS + bool "Debug timer objects" + depends on DEBUG_OBJECTS + help + If you say Y here, additional code will be inserted into the + timer routines to track the life time of timer objects and + validate the timer operations. + config DEBUG_SLAB bool "Debug slab memory allocations" depends on DEBUG_KERNEL && SLAB |