[S390] zcrypt: fix scheduling of hrtimer ap_poll_timer

Every time a request is enqueued or there is some work outstanding
from the ap_tasklet, the ap_poll_timer is scheduled again.
Unfortunately it was permanently called. It looked as if it was
started in the past and thus imediately expired.
This has been changed. First it is checked if the hrtimer is already
expired. Then the expiring time is forwarded and the timer restarted.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index 727a809636d8a63ce93b1271175c3f520ac4455b..ed3dcdea7fe10cb7b521f7ccdb78a1bb5bfc86cc 100644 (file)
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -1145,12 +1145,17 @@ ap_config_timeout(unsigned long ptr)
  */
 static inline void ap_schedule_poll_timer(void)
 {
+       ktime_t hr_time;
        if (ap_using_interrupts() || ap_suspend_flag)
                return;
        if (hrtimer_is_queued(&ap_poll_timer))
                return;
-       hrtimer_start(&ap_poll_timer, ktime_set(0, poll_timeout),
-                     HRTIMER_MODE_ABS);
+       if (ktime_to_ns(hrtimer_expires_remaining(&ap_poll_timer)) <= 0) {
+               hr_time = ktime_set(0, poll_timeout);
+               hrtimer_forward_now(&ap_poll_timer, hr_time);
+               hrtimer_restart(&ap_poll_timer);
+       }
+       return;
 }
 
 /**