---

yaml
---
r: 21247
b: refs/heads/snap-stage3
c: 47cca22
h: refs/heads/master
i:
  21245: a6d5a28
  21243: 082459a
  21239: 32758b2
  21231: 5244a24
  21215: 5b9a735
  21183: 5d0f1d1
  21119: 07db184
  20991: 96fbb2a
v: v3

Author: bblum

[refs]

@@ -1,7 +1,7 @@
 ---
 refs/heads/master: e430a699f2c60890d9b86069fd0c68a70ece7120
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
-refs/heads/snap-stage3: 0229bc4defdaa6bad77269204279ed1a37b3aa9f
+refs/heads/snap-stage3: 47cca22d5455d2d60226ead907fd627784701ef5
 refs/heads/try: ffbe0e0e00374358b789b0037bcb3a577cd218be
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b

branches/snap-stage3/src/libcore/task.rs

@@ -1473,9 +1473,13 @@ extern mod rustrt {
 
     fn rust_task_is_unwinding(task: *rust_task) -> bool;
     fn rust_osmain_sched_id() -> sched_id;
+    #[rust_stack]
     fn rust_task_inhibit_kill(t: *rust_task);
+    #[rust_stack]
     fn rust_task_allow_kill(t: *rust_task);
+    #[rust_stack]
     fn rust_task_inhibit_yield(t: *rust_task);
+    #[rust_stack]
     fn rust_task_allow_yield(t: *rust_task);
     fn rust_task_kill_other(task: *rust_task);
     fn rust_task_kill_all(task: *rust_task);

branches/snap-stage3/src/rt/rust_task.cpp

@@ -631,27 +631,29 @@ rust_task::on_rust_stack() {
     }
 }
 
+// NB: In inhibit_kill and allow_kill, helgrind would complain that we need to
+// hold lifecycle_lock while accessing disallow_kill. Even though another
+// killing task may access disallow_kill concurrently, this is not racy
+// because the killer only cares if this task is blocking, and block() already
+// uses proper locking. See https://github.com/mozilla/rust/issues/3213 .
+
 void
 rust_task::inhibit_kill() {
-    scoped_lock with(lifecycle_lock);
     // Here might be good, though not mandatory, to check if we have to die.
     disallow_kill++;
 }
 
 void
 rust_task::allow_kill() {
-    scoped_lock with(lifecycle_lock);
     assert(disallow_kill > 0 && "Illegal allow_kill(): already killable!");
     disallow_kill--;
 }
 
 void rust_task::inhibit_yield() {
-    scoped_lock with(lifecycle_lock);
     disallow_yield++;
 }
 
 void rust_task::allow_yield() {
-    scoped_lock with(lifecycle_lock);
     assert(disallow_yield > 0 && "Illegal allow_yield(): already yieldable!");
     disallow_yield--;
 }