--- zzzz-none-000/linux-3.10.107/drivers/md/bcache/closure.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/drivers/md/bcache/closure.c 2021-02-04 17:41:59.000000000 +0000 @@ -11,47 +11,12 @@ #include "closure.h" -void closure_queue(struct closure *cl) -{ - struct workqueue_struct *wq = cl->wq; - if (wq) { - INIT_WORK(&cl->work, cl->work.func); - BUG_ON(!queue_work(wq, &cl->work)); - } else - cl->fn(cl); -} -EXPORT_SYMBOL_GPL(closure_queue); - -#define CL_FIELD(type, field) \ - case TYPE_ ## type: \ - return &container_of(cl, struct type, cl)->field - -static struct closure_waitlist *closure_waitlist(struct closure *cl) -{ - switch (cl->type) { - CL_FIELD(closure_with_waitlist, wait); - CL_FIELD(closure_with_waitlist_and_timer, wait); - default: - return NULL; - } -} - -static struct timer_list *closure_timer(struct closure *cl) -{ - switch (cl->type) { - CL_FIELD(closure_with_timer, timer); - CL_FIELD(closure_with_waitlist_and_timer, timer); - default: - return NULL; - } -} - static inline void closure_put_after_sub(struct closure *cl, int flags) { int r = flags & CLOSURE_REMAINING_MASK; BUG_ON(flags & CLOSURE_GUARD_MASK); - BUG_ON(!r && (flags & ~(CLOSURE_DESTRUCTOR|CLOSURE_BLOCKING))); + BUG_ON(!r && (flags & ~CLOSURE_DESTRUCTOR)); /* Must deliver precisely one wakeup */ if (r == 1 && (flags & CLOSURE_SLEEPING)) @@ -59,23 +24,15 @@ if (!r) { if (cl->fn && !(flags & CLOSURE_DESTRUCTOR)) { - /* CLOSURE_BLOCKING might be set - clear it */ atomic_set(&cl->remaining, CLOSURE_REMAINING_INITIALIZER); closure_queue(cl); } else { struct closure *parent = cl->parent; - struct closure_waitlist *wait = closure_waitlist(cl); closure_fn *destructor = cl->fn; closure_debug_destroy(cl); - smp_mb(); - atomic_set(&cl->remaining, -1); - - if (wait) - closure_wake_up(wait); - if (destructor) destructor(cl); @@ -90,21 +47,20 @@ { closure_put_after_sub(cl, atomic_sub_return(v, &cl->remaining)); } -EXPORT_SYMBOL_GPL(closure_sub); +EXPORT_SYMBOL(closure_sub); +/** + * closure_put - decrement a closure's refcount + */ void closure_put(struct closure *cl) { closure_put_after_sub(cl, atomic_dec_return(&cl->remaining)); } -EXPORT_SYMBOL_GPL(closure_put); - -static void set_waiting(struct closure *cl, unsigned long f) -{ -#ifdef CONFIG_BCACHE_CLOSURES_DEBUG - cl->waiting_on = f; -#endif -} +EXPORT_SYMBOL(closure_put); +/** + * closure_wake_up - wake up all closures on a wait list, without memory barrier + */ void __closure_wake_up(struct closure_waitlist *wait_list) { struct llist_node *list; @@ -129,27 +85,34 @@ cl = container_of(reverse, struct closure, list); reverse = llist_next(reverse); - set_waiting(cl, 0); + closure_set_waiting(cl, 0); closure_sub(cl, CLOSURE_WAITING + 1); } } -EXPORT_SYMBOL_GPL(__closure_wake_up); +EXPORT_SYMBOL(__closure_wake_up); -bool closure_wait(struct closure_waitlist *list, struct closure *cl) +/** + * closure_wait - add a closure to a waitlist + * + * @waitlist will own a ref on @cl, which will be released when + * closure_wake_up() is called on @waitlist. + * + */ +bool closure_wait(struct closure_waitlist *waitlist, struct closure *cl) { if (atomic_read(&cl->remaining) & CLOSURE_WAITING) return false; - set_waiting(cl, _RET_IP_); + closure_set_waiting(cl, _RET_IP_); atomic_add(CLOSURE_WAITING + 1, &cl->remaining); - llist_add(&cl->list, &list->list); + llist_add(&cl->list, &waitlist->list); return true; } -EXPORT_SYMBOL_GPL(closure_wait); +EXPORT_SYMBOL(closure_wait); /** - * closure_sync() - sleep until a closure a closure has nothing left to wait on + * closure_sync - sleep until a closure a closure has nothing left to wait on * * Sleeps until the refcount hits 1 - the thread that's running the closure owns * the last refcount. @@ -169,93 +132,7 @@ __closure_end_sleep(cl); } -EXPORT_SYMBOL_GPL(closure_sync); - -/** - * closure_trylock() - try to acquire the closure, without waiting - * @cl: closure to lock - * - * Returns true if the closure was succesfully locked. - */ -bool closure_trylock(struct closure *cl, struct closure *parent) -{ - if (atomic_cmpxchg(&cl->remaining, -1, - CLOSURE_REMAINING_INITIALIZER) != -1) - return false; - - closure_set_ret_ip(cl); - - smp_mb(); - cl->parent = parent; - if (parent) - closure_get(parent); - - closure_debug_create(cl); - return true; -} -EXPORT_SYMBOL_GPL(closure_trylock); - -void __closure_lock(struct closure *cl, struct closure *parent, - struct closure_waitlist *wait_list) -{ - struct closure wait; - closure_init_stack(&wait); - - while (1) { - if (closure_trylock(cl, parent)) - return; - - closure_wait_event_sync(wait_list, &wait, - atomic_read(&cl->remaining) == -1); - } -} -EXPORT_SYMBOL_GPL(__closure_lock); - -static void closure_delay_timer_fn(unsigned long data) -{ - struct closure *cl = (struct closure *) data; - closure_sub(cl, CLOSURE_TIMER + 1); -} - -void do_closure_timer_init(struct closure *cl) -{ - struct timer_list *timer = closure_timer(cl); - - init_timer(timer); - timer->data = (unsigned long) cl; - timer->function = closure_delay_timer_fn; -} -EXPORT_SYMBOL_GPL(do_closure_timer_init); - -bool __closure_delay(struct closure *cl, unsigned long delay, - struct timer_list *timer) -{ - if (atomic_read(&cl->remaining) & CLOSURE_TIMER) - return false; - - BUG_ON(timer_pending(timer)); - - timer->expires = jiffies + delay; - - atomic_add(CLOSURE_TIMER + 1, &cl->remaining); - add_timer(timer); - return true; -} -EXPORT_SYMBOL_GPL(__closure_delay); - -void __closure_flush(struct closure *cl, struct timer_list *timer) -{ - if (del_timer(timer)) - closure_sub(cl, CLOSURE_TIMER + 1); -} -EXPORT_SYMBOL_GPL(__closure_flush); - -void __closure_flush_sync(struct closure *cl, struct timer_list *timer) -{ - if (del_timer_sync(timer)) - closure_sub(cl, CLOSURE_TIMER + 1); -} -EXPORT_SYMBOL_GPL(__closure_flush_sync); +EXPORT_SYMBOL(closure_sync); #ifdef CONFIG_BCACHE_CLOSURES_DEBUG @@ -273,7 +150,7 @@ list_add(&cl->all, &closure_list); spin_unlock_irqrestore(&closure_list_lock, flags); } -EXPORT_SYMBOL_GPL(closure_debug_create); +EXPORT_SYMBOL(closure_debug_create); void closure_debug_destroy(struct closure *cl) { @@ -286,12 +163,10 @@ list_del(&cl->all); spin_unlock_irqrestore(&closure_list_lock, flags); } -EXPORT_SYMBOL_GPL(closure_debug_destroy); +EXPORT_SYMBOL(closure_debug_destroy); static struct dentry *debug; -#define work_data_bits(work) ((unsigned long *)(&(work)->data)) - static int debug_seq_show(struct seq_file *f, void *data) { struct closure *cl; @@ -304,14 +179,12 @@ cl, (void *) cl->ip, cl->fn, cl->parent, r & CLOSURE_REMAINING_MASK); - seq_printf(f, "%s%s%s%s%s%s\n", - test_bit(WORK_STRUCT_PENDING, + seq_printf(f, "%s%s%s%s\n", + test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(&cl->work)) ? "Q" : "", r & CLOSURE_RUNNING ? "R" : "", - r & CLOSURE_BLOCKING ? "B" : "", r & CLOSURE_STACK ? "S" : "", - r & CLOSURE_SLEEPING ? "Sl" : "", - r & CLOSURE_TIMER ? "T" : ""); + r & CLOSURE_SLEEPING ? "Sl" : ""); if (r & CLOSURE_WAITING) seq_printf(f, " W %pF\n",