diff options
Diffstat (limited to 'lib/closure.c')
| -rw-r--r-- | lib/closure.c | 47 |
1 files changed, 45 insertions, 2 deletions
diff --git a/lib/closure.c b/lib/closure.c index c16540552d61..2e1ee9fdec08 100644 --- a/lib/closure.c +++ b/lib/closure.c @@ -17,12 +17,18 @@ 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)); + if (WARN(flags & CLOSURE_GUARD_MASK, + "closure has guard bits set: %x (%u)", + flags & CLOSURE_GUARD_MASK, (unsigned) __fls(r))) + r &= ~CLOSURE_GUARD_MASK; if (!r) { smp_acquire__after_ctrl_dep(); + WARN(flags & ~CLOSURE_DESTRUCTOR, + "closure ref hit 0 with incorrect flags set: %x (%u)", + flags & ~CLOSURE_DESTRUCTOR, (unsigned) __fls(flags)); + cl->closure_get_happened = false; if (cl->fn && !(flags & CLOSURE_DESTRUCTOR)) { @@ -139,6 +145,43 @@ void __sched __closure_sync(struct closure *cl) } EXPORT_SYMBOL(__closure_sync); +int __sched __closure_sync_timeout(struct closure *cl, unsigned long timeout) +{ + struct closure_syncer s = { .task = current }; + int ret = 0; + + cl->s = &s; + continue_at(cl, closure_sync_fn, NULL); + + while (1) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (s.done) + break; + if (!timeout) { + /* + * Carefully undo the continue_at() - but only if it + * hasn't completed, i.e. the final closure_put() hasn't + * happened yet: + */ + unsigned old, new, v = atomic_read(&cl->remaining); + do { + old = v; + if (!old || (old & CLOSURE_RUNNING)) + goto success; + + new = old + CLOSURE_REMAINING_INITIALIZER; + } while ((v = atomic_cmpxchg(&cl->remaining, old, new)) != old); + ret = -ETIME; + } + + timeout = schedule_timeout(timeout); + } +success: + __set_current_state(TASK_RUNNING); + return ret; +} +EXPORT_SYMBOL(__closure_sync_timeout); + #ifdef CONFIG_DEBUG_CLOSURES static LIST_HEAD(closure_list); |