diff options
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 4 | ||||
| -rw-r--r-- | include/linux/workqueue.h | 38 | ||||
| -rw-r--r-- | kernel/workqueue.c | 131 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 8 |
4 files changed, 166 insertions, 15 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 324f2a44c221..29e6744f51e3 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -687,7 +687,7 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu) .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done), }; - INIT_WORK(&c_idle.work, do_fork_idle); + INIT_WORK_ON_STACK(&c_idle.work, do_fork_idle); alternatives_smp_switch(1); @@ -713,6 +713,7 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu) if (IS_ERR(c_idle.idle)) { printk("failed fork for CPU %d\n", cpu); + destroy_work_on_stack(&c_idle.work); return PTR_ERR(c_idle.idle); } @@ -831,6 +832,7 @@ do_rest: smpboot_restore_warm_reset_vector(); } + destroy_work_on_stack(&c_idle.work); return boot_error; } diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index cf24c20de9e4..9466e860d8c2 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -25,6 +25,7 @@ typedef void (*work_func_t)(struct work_struct *work); struct work_struct { atomic_long_t data; #define WORK_STRUCT_PENDING 0 /* T if work item pending execution */ +#define WORK_STRUCT_STATIC 1 /* static initializer (debugobjects) */ #define WORK_STRUCT_FLAG_MASK (3UL) #define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK) struct list_head entry; @@ -35,6 +36,7 @@ struct work_struct { }; #define WORK_DATA_INIT() ATOMIC_LONG_INIT(0) +#define WORK_DATA_STATIC_INIT() ATOMIC_LONG_INIT(2) struct delayed_work { struct work_struct work; @@ -63,7 +65,7 @@ struct execute_work { #endif #define __WORK_INITIALIZER(n, f) { \ - .data = WORK_DATA_INIT(), \ + .data = WORK_DATA_STATIC_INIT(), \ .entry = { &(n).entry, &(n).entry }, \ .func = (f), \ __WORK_INIT_LOCKDEP_MAP(#n, &(n)) \ @@ -91,6 +93,14 @@ struct execute_work { #define PREPARE_DELAYED_WORK(_work, _func) \ PREPARE_WORK(&(_work)->work, (_func)) +#ifdef CONFIG_DEBUG_OBJECTS_WORK +extern void __init_work(struct work_struct *work, int onstack); +extern void destroy_work_on_stack(struct work_struct *work); +#else +static inline void __init_work(struct work_struct *work, int onstack) { } +static inline void destroy_work_on_stack(struct work_struct *work) { } +#endif + /* * initialize all of a work item in one go * @@ -99,24 +109,36 @@ struct execute_work { * to generate better code. */ #ifdef CONFIG_LOCKDEP -#define INIT_WORK(_work, _func) \ +#define __INIT_WORK(_work, _func, _onstack) \ do { \ static struct lock_class_key __key; \ \ + __init_work((_work), _onstack); \ (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \ lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\ INIT_LIST_HEAD(&(_work)->entry); \ PREPARE_WORK((_work), (_func)); \ } while (0) #else -#define INIT_WORK(_work, _func) \ +#define __INIT_WORK(_work, _func, _onstack) \ do { \ + __init_work((_work), _onstack); \ (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \ INIT_LIST_HEAD(&(_work)->entry); \ PREPARE_WORK((_work), (_func)); \ } while (0) #endif +#define INIT_WORK(_work, _func) \ + do { \ + __INIT_WORK((_work), (_func), 0); \ + } while (0) + +#define INIT_WORK_ON_STACK(_work, _func) \ + do { \ + __INIT_WORK((_work), (_func), 1); \ + } while (0) + #define INIT_DELAYED_WORK(_work, _func) \ do { \ INIT_WORK(&(_work)->work, (_func)); \ @@ -125,22 +147,16 @@ struct execute_work { #define INIT_DELAYED_WORK_ON_STACK(_work, _func) \ do { \ - INIT_WORK(&(_work)->work, (_func)); \ + INIT_WORK_ON_STACK(&(_work)->work, (_func)); \ init_timer_on_stack(&(_work)->timer); \ } while (0) -#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \ +#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \ do { \ INIT_WORK(&(_work)->work, (_func)); \ init_timer_deferrable(&(_work)->timer); \ } while (0) -#define INIT_DELAYED_WORK_ON_STACK(_work, _func) \ - do { \ - INIT_WORK(&(_work)->work, (_func)); \ - init_timer_on_stack(&(_work)->timer); \ - } while (0) - /** * work_pending - Find out whether a work item is currently pending * @work: The work item in question diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 67e526b6ae81..dee48658805c 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -68,6 +68,116 @@ struct workqueue_struct { #endif }; +#ifdef CONFIG_DEBUG_OBJECTS_WORK + +static struct debug_obj_descr work_debug_descr; + +/* + * fixup_init is called when: + * - an active object is initialized + */ +static int work_fixup_init(void *addr, enum debug_obj_state state) +{ + struct work_struct *work = addr; + + switch (state) { + case ODEBUG_STATE_ACTIVE: + cancel_work_sync(work); + debug_object_init(work, &work_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 work_fixup_activate(void *addr, enum debug_obj_state state) +{ + struct work_struct *work = addr; + + switch (state) { + + case ODEBUG_STATE_NOTAVAILABLE: + /* + * This is not really a fixup. The work struct was + * statically initialized. We just make sure that it + * is tracked in the object tracker. + */ + if (test_bit(WORK_STRUCT_STATIC, work_data_bits(work))) { + debug_object_init(work, &work_debug_descr); + debug_object_activate(work, &work_debug_descr); + return 0; + } + 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 work_fixup_free(void *addr, enum debug_obj_state state) +{ + struct work_struct *work = addr; + + switch (state) { + case ODEBUG_STATE_ACTIVE: + cancel_work_sync(work); + debug_object_free(work, &work_debug_descr); + return 1; + default: + return 0; + } +} + +static struct debug_obj_descr work_debug_descr = { + .name = "work_struct", + .fixup_init = work_fixup_init, + .fixup_activate = work_fixup_activate, + .fixup_free = work_fixup_free, +}; + +static inline void debug_work_activate(struct work_struct *work) +{ + debug_object_activate(work, &work_debug_descr); +} + +static inline void debug_work_deactivate(struct work_struct *work) +{ + debug_object_deactivate(work, &work_debug_descr); +} + +void __init_work(struct work_struct *work, int onstack) +{ + if (onstack) + debug_object_init_on_stack(work, &work_debug_descr); + else + debug_object_init(work, &work_debug_descr); +} +EXPORT_SYMBOL_GPL(__init_work); + +void destroy_work_on_stack(struct work_struct *work) +{ + debug_object_free(work, &work_debug_descr); +} +EXPORT_SYMBOL_GPL(destroy_work_on_stack); + +#else +static inline void debug_work_activate(struct work_struct *work) { } +static inline void debug_work_deactivate(struct work_struct *work) { } +#endif + /* Serializes the accesses to the list of workqueues. */ static DEFINE_SPINLOCK(workqueue_lock); static LIST_HEAD(workqueues); @@ -145,6 +255,7 @@ static void __queue_work(struct cpu_workqueue_struct *cwq, { unsigned long flags; + debug_work_activate(work); spin_lock_irqsave(&cwq->lock, flags); insert_work(cwq, work, &cwq->worklist); spin_unlock_irqrestore(&cwq->lock, flags); @@ -280,6 +391,7 @@ static void run_workqueue(struct cpu_workqueue_struct *cwq) struct lockdep_map lockdep_map = work->lockdep_map; #endif trace_workqueue_execution(cwq->thread, work); + debug_work_deactivate(work); cwq->current_work = work; list_del_init(cwq->worklist.next); spin_unlock_irq(&cwq->lock); @@ -350,11 +462,18 @@ static void wq_barrier_func(struct work_struct *work) static void insert_wq_barrier(struct cpu_workqueue_struct *cwq, struct wq_barrier *barr, struct list_head *head) { - INIT_WORK(&barr->work, wq_barrier_func); + /* + * debugobject calls are safe here even with cwq->lock locked + * as we know for sure that this will not trigger any of the + * checks and call back into the fixup functions where we + * might deadlock. + */ + INIT_WORK_ON_STACK(&barr->work, wq_barrier_func); __set_bit(WORK_STRUCT_PENDING, work_data_bits(&barr->work)); init_completion(&barr->done); + debug_work_activate(&barr->work); insert_work(cwq, &barr->work, head); } @@ -372,8 +491,10 @@ static int flush_cpu_workqueue(struct cpu_workqueue_struct *cwq) } spin_unlock_irq(&cwq->lock); - if (active) + if (active) { wait_for_completion(&barr.done); + destroy_work_on_stack(&barr.work); + } return active; } @@ -451,6 +572,7 @@ out: return 0; wait_for_completion(&barr.done); + destroy_work_on_stack(&barr.work); return 1; } EXPORT_SYMBOL_GPL(flush_work); @@ -485,6 +607,7 @@ static int try_to_grab_pending(struct work_struct *work) */ smp_rmb(); if (cwq == get_wq_data(work)) { + debug_work_deactivate(work); list_del_init(&work->entry); ret = 1; } @@ -507,8 +630,10 @@ static void wait_on_cpu_work(struct cpu_workqueue_struct *cwq, } spin_unlock_irq(&cwq->lock); - if (unlikely(running)) + if (unlikely(running)) { wait_for_completion(&barr.done); + destroy_work_on_stack(&barr.work); + } } static void wait_on_work(struct work_struct *work) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 96c620a0c59c..2f22cf4576db 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -298,6 +298,14 @@ config DEBUG_OBJECTS_TIMERS timer routines to track the life time of timer objects and validate the timer operations. +config DEBUG_OBJECTS_WORK + bool "Debug work objects" + depends on DEBUG_OBJECTS + help + If you say Y here, additional code will be inserted into the + work queue routines to track the life time of work objects and + validate the work operations. + config DEBUG_OBJECTS_ENABLE_DEFAULT int "debug_objects bootup default value (0-1)" range 0 1 |