s390x/kvm: run guest triggered resets on the target vcpu thread

Currently, load_normal_reset() and modified_clear_reset() as triggered
by a guest vcpu will initiate cpu resets on the current vcpu thread for
all cpus. The reset should happen on the individual vcpu thread
instead, so let's use run_on_cpu() for this.

This avoids calls to synchronize_rcu() in the kernel.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index b13761d925..17a3df4d06 100644
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -353,6 +353,21 @@ static inline hwaddr decode_basedisp_s(CPUS390XState *env, uint32_t ipb)
 /* Base/displacement are at the same locations. */
 #define decode_basedisp_rs decode_basedisp_s
 
+/* helper functions for run_on_cpu() */
+static inline void s390_do_cpu_reset(void *arg)
+{
+    CPUState *cs = arg;
+    S390CPUClass *scc = S390_CPU_GET_CLASS(cs);
+
+    scc->cpu_reset(cs);
+}
+static inline void s390_do_cpu_full_reset(void *arg)
+{
+    CPUState *cs = arg;
+
+    cpu_reset(cs);
+}
+
 void s390x_tod_timer(void *opaque);
 void s390x_cpu_timer(void *opaque);