[S390] hwsampler: allow cpu hotplug

The hardware sample cpu hotplug notifier always returns NOTIFY_BAD.
That will prevent cpu hotplug if the machine is enabled for hardware
sampling even if it is not used. Fix the cpu hotplug notifier and
allow cpu hotplug if hardware sampling is unused.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

diff --git a/arch/s390/oprofile/hwsampler.c b/arch/s390/oprofile/hwsampler.c
index 4634c9ef97226cba6dcaab5dc6037e290f72fa34..4552ce40c81a5086ad550e21092c78b36ad3b7c3 100644 (file)
--- a/arch/s390/oprofile/hwsampler.c
+++ b/arch/s390/oprofile/hwsampler.c
@@ -580,7 +580,7 @@ static int hws_cpu_callback(struct notifier_block *nfb,
 {
        /* We do not have sampler space available for all possible CPUs.
           All CPUs should be online when hw sampling is activated. */
-       return NOTIFY_BAD;
+       return (hws_state <= HWS_DEALLOCATED) ? NOTIFY_OK : NOTIFY_BAD;
 }
 
 static struct notifier_block hws_cpu_notifier = {