diff options
Diffstat (limited to 'kernel/async.c')
| -rw-r--r-- | kernel/async.c | 76 |
1 files changed, 57 insertions, 19 deletions
diff --git a/kernel/async.c b/kernel/async.c index bd0c168a3bb..9d311838485 100644 --- a/kernel/async.c +++ b/kernel/async.c @@ -62,8 +62,10 @@ static async_cookie_t next_cookie = 1; #define MAX_WORK 32768 static LIST_HEAD(async_pending); -static LIST_HEAD(async_running); +static ASYNC_DOMAIN(async_running); +static LIST_HEAD(async_domains); static DEFINE_SPINLOCK(async_lock); +static DEFINE_MUTEX(async_register_mutex); struct async_entry { struct list_head list; @@ -71,7 +73,7 @@ struct async_entry { async_cookie_t cookie; async_func_ptr *func; void *data; - struct list_head *running; + struct async_domain *running; }; static DECLARE_WAIT_QUEUE_HEAD(async_done); @@ -82,13 +84,12 @@ static atomic_t entry_count; /* * MUST be called with the lock held! */ -static async_cookie_t __lowest_in_progress(struct list_head *running) +static async_cookie_t __lowest_in_progress(struct async_domain *running) { struct async_entry *entry; - if (!list_empty(running)) { - entry = list_first_entry(running, - struct async_entry, list); + if (!list_empty(&running->domain)) { + entry = list_first_entry(&running->domain, typeof(*entry), list); return entry->cookie; } @@ -99,7 +100,7 @@ static async_cookie_t __lowest_in_progress(struct list_head *running) return next_cookie; /* "infinity" value */ } -static async_cookie_t lowest_in_progress(struct list_head *running) +static async_cookie_t lowest_in_progress(struct async_domain *running) { unsigned long flags; async_cookie_t ret; @@ -119,10 +120,11 @@ static void async_run_entry_fn(struct work_struct *work) container_of(work, struct async_entry, work); unsigned long flags; ktime_t uninitialized_var(calltime), delta, rettime; + struct async_domain *running = entry->running; /* 1) move self to the running queue */ spin_lock_irqsave(&async_lock, flags); - list_move_tail(&entry->list, entry->running); + list_move_tail(&entry->list, &running->domain); spin_unlock_irqrestore(&async_lock, flags); /* 2) run (and print duration) */ @@ -145,6 +147,8 @@ static void async_run_entry_fn(struct work_struct *work) /* 3) remove self from the running queue */ spin_lock_irqsave(&async_lock, flags); list_del(&entry->list); + if (running->registered && --running->count == 0) + list_del_init(&running->node); /* 4) free the entry */ kfree(entry); @@ -156,7 +160,7 @@ static void async_run_entry_fn(struct work_struct *work) wake_up(&async_done); } -static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct list_head *running) +static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct async_domain *running) { struct async_entry *entry; unsigned long flags; @@ -187,6 +191,8 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct l spin_lock_irqsave(&async_lock, flags); newcookie = entry->cookie = next_cookie++; list_add_tail(&entry->list, &async_pending); + if (running->registered && running->count++ == 0) + list_add_tail(&running->node, &async_domains); atomic_inc(&entry_count); spin_unlock_irqrestore(&async_lock, flags); @@ -223,7 +229,7 @@ EXPORT_SYMBOL_GPL(async_schedule); * Note: This function may be called from atomic or non-atomic contexts. */ async_cookie_t async_schedule_domain(async_func_ptr *ptr, void *data, - struct list_head *running) + struct async_domain *running) { return __async_schedule(ptr, data, running); } @@ -236,22 +242,52 @@ EXPORT_SYMBOL_GPL(async_schedule_domain); */ void async_synchronize_full(void) { + mutex_lock(&async_register_mutex); do { - async_synchronize_cookie(next_cookie); - } while (!list_empty(&async_running) || !list_empty(&async_pending)); + struct async_domain *domain = NULL; + + spin_lock_irq(&async_lock); + if (!list_empty(&async_domains)) + domain = list_first_entry(&async_domains, typeof(*domain), node); + spin_unlock_irq(&async_lock); + + async_synchronize_cookie_domain(next_cookie, domain); + } while (!list_empty(&async_domains)); + mutex_unlock(&async_register_mutex); } EXPORT_SYMBOL_GPL(async_synchronize_full); /** + * async_unregister_domain - ensure no more anonymous waiters on this domain + * @domain: idle domain to flush out of any async_synchronize_full instances + * + * async_synchronize_{cookie|full}_domain() are not flushed since callers + * of these routines should know the lifetime of @domain + * + * Prefer ASYNC_DOMAIN_EXCLUSIVE() declarations over flushing + */ +void async_unregister_domain(struct async_domain *domain) +{ + mutex_lock(&async_register_mutex); + spin_lock_irq(&async_lock); + WARN_ON(!domain->registered || !list_empty(&domain->node) || + !list_empty(&domain->domain)); + domain->registered = 0; + spin_unlock_irq(&async_lock); + mutex_unlock(&async_register_mutex); +} +EXPORT_SYMBOL_GPL(async_unregister_domain); + +/** * async_synchronize_full_domain - synchronize all asynchronous function within a certain domain - * @list: running list to synchronize on + * @domain: running list to synchronize on * * This function waits until all asynchronous function calls for the - * synchronization domain specified by the running list @list have been done. + * synchronization domain specified by the running list @domain have been done. */ -void async_synchronize_full_domain(struct list_head *list) +void async_synchronize_full_domain(struct async_domain *domain) { - async_synchronize_cookie_domain(next_cookie, list); + async_synchronize_cookie_domain(next_cookie, domain); } EXPORT_SYMBOL_GPL(async_synchronize_full_domain); @@ -261,14 +297,16 @@ EXPORT_SYMBOL_GPL(async_synchronize_full_domain); * @running: running list to synchronize on * * This function waits until all asynchronous function calls for the - * synchronization domain specified by the running list @list submitted + * synchronization domain specified by running list @running submitted * prior to @cookie have been done. */ -void async_synchronize_cookie_domain(async_cookie_t cookie, - struct list_head *running) +void async_synchronize_cookie_domain(async_cookie_t cookie, struct async_domain *running) { ktime_t uninitialized_var(starttime), delta, endtime; + if (!running) + return; + if (initcall_debug && system_state == SYSTEM_BOOTING) { printk(KERN_DEBUG "async_waiting @ %i\n", task_pid_nr(current)); starttime = ktime_get(); |