*/
struct closure;
+struct closure_syncer;
typedef void (closure_fn) (struct closure *);
struct closure_waitlist {
* 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
* 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)
union {
struct {
struct workqueue_struct *wq;
- struct task_struct *task;
+ struct closure_syncer *s;
struct llist_node list;
closure_fn *fn;
};
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
#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);
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;
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);
}
/**
* 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 { \