[PATCH RT 02/10] rtmutex: Make lock_killable work

From: Steven Rostedt
Date: Thu Nov 23 2017 - 00:35:08 EST


4.4.97-rt111-rc2 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Locking an rt mutex killable does not work because signal handling is
restricted to TASK_INTERRUPTIBLE.

Use signal_pending_state() unconditionaly.

Cc: rt-stable@xxxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/locking/rtmutex.c | 19 +++++++------------
1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 0e9a6260441d..552dc6dd3a79 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1672,18 +1672,13 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
if (try_to_take_rt_mutex(lock, current, waiter))
break;

- /*
- * TASK_INTERRUPTIBLE checks for signals and
- * timeout. Ignored otherwise.
- */
- if (unlikely(state == TASK_INTERRUPTIBLE)) {
- /* Signal pending? */
- if (signal_pending(current))
- ret = -EINTR;
- if (timeout && !timeout->task)
- ret = -ETIMEDOUT;
- if (ret)
- break;
+ if (timeout && !timeout->task) {
+ ret = -ETIMEDOUT;
+ break;
+ }
+ if (signal_pending_state(state, current)) {
+ ret = -EINTR;
+ break;
}

if (ww_ctx && ww_ctx->acquired > 0) {
--
2.13.2