Merge tag 'mm-nonmm-stable-2024-05-19-11-56' of git://git.kernel.org/pub/scm/linux...

[linux-block.git] / lib / closure.c

diff --git a/lib/closure.c b/lib/closure.c
index c16540552d61bc14121b034a9d6e302045ff0dc5..07409e9e35a53ef96d0957c396c4685ce69a7f05 100644 (file)
--- a/lib/closure.c
+++ b/lib/closure.c
@@ -139,6 +139,43 @@ 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);