diff options
Diffstat (limited to 'drivers/md/bcache/closure.c')
| -rw-r--r-- | drivers/md/bcache/closure.c | 220 |
1 files changed, 0 insertions, 220 deletions
diff --git a/drivers/md/bcache/closure.c b/drivers/md/bcache/closure.c deleted file mode 100644 index 864e673aec39..000000000000 --- a/drivers/md/bcache/closure.c +++ /dev/null @@ -1,220 +0,0 @@ -/* - * Asynchronous refcounty things - * - * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> - * Copyright 2012 Google, Inc. - */ - -#include <linux/debugfs.h> -#include <linux/module.h> -#include <linux/seq_file.h> - -#include "closure.h" - -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)); - - /* Must deliver precisely one wakeup */ - if (r == 1 && (flags & CLOSURE_SLEEPING)) - wake_up_process(cl->task); - - if (!r) { - if (cl->fn && !(flags & CLOSURE_DESTRUCTOR)) { - atomic_set(&cl->remaining, - CLOSURE_REMAINING_INITIALIZER); - closure_queue(cl); - } else { - struct closure *parent = cl->parent; - closure_fn *destructor = cl->fn; - - closure_debug_destroy(cl); - - if (destructor) - destructor(cl); - - if (parent) - closure_put(parent); - } - } -} - -/* For clearing flags with the same atomic op as a put */ -void closure_sub(struct closure *cl, int v) -{ - closure_put_after_sub(cl, atomic_sub_return(v, &cl->remaining)); -} -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(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; - struct closure *cl; - struct llist_node *reverse = NULL; - - list = llist_del_all(&wait_list->list); - - /* We first reverse the list to preserve FIFO ordering and fairness */ - - while (list) { - struct llist_node *t = list; - list = llist_next(list); - - t->next = reverse; - reverse = t; - } - - /* Then do the wakeups */ - - while (reverse) { - cl = container_of(reverse, struct closure, list); - reverse = llist_next(reverse); - - closure_set_waiting(cl, 0); - closure_sub(cl, CLOSURE_WAITING + 1); - } -} -EXPORT_SYMBOL(__closure_wake_up); - -/** - * 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; - - closure_set_waiting(cl, _RET_IP_); - atomic_add(CLOSURE_WAITING + 1, &cl->remaining); - llist_add(&cl->list, &waitlist->list); - - return true; -} -EXPORT_SYMBOL(closure_wait); - -/** - * closure_sync - sleep until 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. - */ -void closure_sync(struct closure *cl) -{ - while (1) { - __closure_start_sleep(cl); - closure_set_ret_ip(cl); - - if ((atomic_read(&cl->remaining) & - CLOSURE_REMAINING_MASK) == 1) - break; - - schedule(); - } - - __closure_end_sleep(cl); -} -EXPORT_SYMBOL(closure_sync); - -#ifdef CONFIG_BCACHE_CLOSURES_DEBUG - -static LIST_HEAD(closure_list); -static DEFINE_SPINLOCK(closure_list_lock); - -void closure_debug_create(struct closure *cl) -{ - unsigned long flags; - - BUG_ON(cl->magic == CLOSURE_MAGIC_ALIVE); - cl->magic = CLOSURE_MAGIC_ALIVE; - - spin_lock_irqsave(&closure_list_lock, flags); - list_add(&cl->all, &closure_list); - spin_unlock_irqrestore(&closure_list_lock, flags); -} -EXPORT_SYMBOL(closure_debug_create); - -void closure_debug_destroy(struct closure *cl) -{ - unsigned long flags; - - BUG_ON(cl->magic != CLOSURE_MAGIC_ALIVE); - cl->magic = CLOSURE_MAGIC_DEAD; - - spin_lock_irqsave(&closure_list_lock, flags); - list_del(&cl->all); - spin_unlock_irqrestore(&closure_list_lock, flags); -} -EXPORT_SYMBOL(closure_debug_destroy); - -static struct dentry *debug; - -static int debug_seq_show(struct seq_file *f, void *data) -{ - struct closure *cl; - spin_lock_irq(&closure_list_lock); - - list_for_each_entry(cl, &closure_list, all) { - int r = atomic_read(&cl->remaining); - - seq_printf(f, "%p: %pF -> %pf p %p r %i ", - cl, (void *) cl->ip, cl->fn, cl->parent, - r & CLOSURE_REMAINING_MASK); - - 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_STACK ? "S" : "", - r & CLOSURE_SLEEPING ? "Sl" : ""); - - if (r & CLOSURE_WAITING) - seq_printf(f, " W %pF\n", - (void *) cl->waiting_on); - - seq_printf(f, "\n"); - } - - spin_unlock_irq(&closure_list_lock); - return 0; -} - -static int debug_seq_open(struct inode *inode, struct file *file) -{ - return single_open(file, debug_seq_show, NULL); -} - -static const struct file_operations debug_ops = { - .owner = THIS_MODULE, - .open = debug_seq_open, - .read = seq_read, - .release = single_release -}; - -void __init closure_debug_init(void) -{ - debug = debugfs_create_file("closures", 0400, NULL, NULL, &debug_ops); -} - -#endif - -MODULE_AUTHOR("Kent Overstreet <koverstreet@google.com>"); -MODULE_LICENSE("GPL"); |