Subject: sched: ttwu: Return success when only changing the saved_state value From: Thomas Gleixner Date: Tue, 13 Dec 2011 21:42:19 +0100 Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.1/patches-4.1.3-rt3.tar.xz When a task blocks on a rt lock, it saves the current state in p->saved_state, so a lock related wake up will not destroy the original state. When a real wakeup happens, while the task is running due to a lock wakeup already, we update p->saved_state to TASK_RUNNING, but we do not return success, which might cause another wakeup in the waitqueue code and the task remains in the waitqueue list. Return success in that case as well. Signed-off-by: Thomas Gleixner --- kernel/sched/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1728,8 +1728,10 @@ try_to_wake_up(struct task_struct *p, un * if the wakeup condition is true. */ if (!(wake_flags & WF_LOCK_SLEEPER)) { - if (p->saved_state & state) + if (p->saved_state & state) { p->saved_state = TASK_RUNNING; + success = 1; + } } goto out; }