[patch 6/6] posix-cpu-timers: Make PID=0 and PID=self handling consistent

Thomas Gleixner
2019-09-05T12:12:16Z

If the PID encoded into the clock id is 0 then the target is either the
calling thread itself or the process to which it belongs.

If the current thread encodes its own PID on a process wide clock then
there is no reason not to treat it in the same way as the PID=0 case.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
kernel/time/posix-cpu-timers.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -90,7 +90,14 @@ static struct task_struct *lookup_task(c

} else {
/*
- * For processes require that p is group leader.
+ * Timer is going to be attached to a process. If p is
+ * current then treat it like the PID=0 case above.
+ */
+ if (p == current)
+ return current->group_leader;
+
+ /*
+ * For foreign processes require that p is group leader.
*/
if (!has_group_leader_pid(p))
return NULL;