diff options
Diffstat (limited to 'drivers/md/bcache/closure.h')
| -rw-r--r-- | drivers/md/bcache/closure.h | 60 |
1 files changed, 23 insertions, 37 deletions
diff --git a/drivers/md/bcache/closure.h b/drivers/md/bcache/closure.h index ccfbea6f9f6b..3b9dfc9962ad 100644 --- a/drivers/md/bcache/closure.h +++ b/drivers/md/bcache/closure.h @@ -103,6 +103,7 @@ */ struct closure; +struct closure_syncer; typedef void (closure_fn) (struct closure *); struct closure_waitlist { @@ -115,10 +116,6 @@ enum closure_state { * the thread that owns the closure, and cleared by the thread that's * waking up the closure. * - * CLOSURE_SLEEPING: Must be set before a thread uses a closure to sleep - * - indicates that cl->task is valid and closure_put() may wake it up. - * Only set or cleared by the thread that owns the closure. - * * The rest are for debugging and don't affect behaviour: * * CLOSURE_RUNNING: Set when a closure is running (i.e. by @@ -128,22 +125,16 @@ enum closure_state { * continue_at() and closure_return() clear it for you, if you're doing * something unusual you can use closure_set_dead() which also helps * annotate where references are being transferred. - * - * CLOSURE_STACK: Sanity check - remaining should never hit 0 on a - * closure with this flag set */ - CLOSURE_BITS_START = (1 << 23), - CLOSURE_DESTRUCTOR = (1 << 23), - CLOSURE_WAITING = (1 << 25), - CLOSURE_SLEEPING = (1 << 27), - CLOSURE_RUNNING = (1 << 29), - CLOSURE_STACK = (1 << 31), + CLOSURE_BITS_START = (1U << 26), + CLOSURE_DESTRUCTOR = (1U << 26), + CLOSURE_WAITING = (1U << 28), + CLOSURE_RUNNING = (1U << 30), }; #define CLOSURE_GUARD_MASK \ - ((CLOSURE_DESTRUCTOR|CLOSURE_WAITING|CLOSURE_SLEEPING| \ - CLOSURE_RUNNING|CLOSURE_STACK) << 1) + ((CLOSURE_DESTRUCTOR|CLOSURE_WAITING|CLOSURE_RUNNING) << 1) #define CLOSURE_REMAINING_MASK (CLOSURE_BITS_START - 1) #define CLOSURE_REMAINING_INITIALIZER (1|CLOSURE_RUNNING) @@ -152,7 +143,7 @@ struct closure { union { struct { struct workqueue_struct *wq; - struct task_struct *task; + struct closure_syncer *s; struct llist_node list; closure_fn *fn; }; @@ -178,7 +169,19 @@ void closure_sub(struct closure *cl, int v); void closure_put(struct closure *cl); void __closure_wake_up(struct closure_waitlist *list); bool closure_wait(struct closure_waitlist *list, struct closure *cl); -void closure_sync(struct closure *cl); +void __closure_sync(struct closure *cl); + +/** + * 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. + */ +static inline void closure_sync(struct closure *cl) +{ + if ((atomic_read(&cl->remaining) & CLOSURE_REMAINING_MASK) != 1) + __closure_sync(cl); +} #ifdef CONFIG_BCACHE_CLOSURES_DEBUG @@ -215,24 +218,6 @@ static inline void closure_set_waiting(struct closure *cl, unsigned long f) #endif } -static inline void __closure_end_sleep(struct closure *cl) -{ - __set_current_state(TASK_RUNNING); - - if (atomic_read(&cl->remaining) & CLOSURE_SLEEPING) - atomic_sub(CLOSURE_SLEEPING, &cl->remaining); -} - -static inline void __closure_start_sleep(struct closure *cl) -{ - closure_set_ip(cl); - cl->task = current; - set_current_state(TASK_UNINTERRUPTIBLE); - - if (!(atomic_read(&cl->remaining) & CLOSURE_SLEEPING)) - atomic_add(CLOSURE_SLEEPING, &cl->remaining); -} - static inline void closure_set_stopped(struct closure *cl) { atomic_sub(CLOSURE_RUNNING, &cl->remaining); @@ -241,7 +226,6 @@ static inline void closure_set_stopped(struct closure *cl) static inline void set_closure_fn(struct closure *cl, closure_fn *fn, struct workqueue_struct *wq) { - BUG_ON(object_is_on_stack(cl)); closure_set_ip(cl); cl->fn = fn; cl->wq = wq; @@ -300,7 +284,7 @@ static inline void closure_init(struct closure *cl, struct closure *parent) static inline void closure_init_stack(struct closure *cl) { memset(cl, 0, sizeof(struct closure)); - atomic_set(&cl->remaining, CLOSURE_REMAINING_INITIALIZER|CLOSURE_STACK); + atomic_set(&cl->remaining, CLOSURE_REMAINING_INITIALIZER); } /** @@ -322,6 +306,8 @@ static inline void closure_wake_up(struct closure_waitlist *list) * This is because after calling continue_at() you no longer have a ref on @cl, * and whatever @cl owns may be freed out from under you - a running closure fn * has a ref on its own closure which continue_at() drops. + * + * Note you are expected to immediately return after using this macro. */ #define continue_at(_cl, _fn, _wq) \ do { \ |