diff mbox series

[GIT,PULL,2/2] KVM: s390: add tracepoint in gmap notifier

Message ID 20231030092101.66014-3-frankja@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series [GIT,PULL,1/2] KVM: s390: add stat counter for shadow gmap events | expand

Commit Message

Janosch Frank Oct. 30, 2023, 9:08 a.m. UTC 
From: Nico Boehr <nrb@linux.ibm.com>

The gmap notifier is called for changes in table entries with the
notifier bit set. To diagnose performance issues, it can be useful to
see what causes certain changes in the gmap.

Hence, add a tracepoint in the gmap notifier.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20231009093304.2555344-3-nrb@linux.ibm.com
Message-Id: <20231009093304.2555344-3-nrb@linux.ibm.com>
---
 arch/s390/kvm/kvm-s390.c   |  2 ++
 arch/s390/kvm/trace-s390.h | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+)
diff mbox series

Patch

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index b42493110d76..11676b81e6bf 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4060,6 +4060,8 @@  static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
 	unsigned long prefix;
 	unsigned long i;
 
+	trace_kvm_s390_gmap_notifier(start, end, gmap_is_shadow(gmap));
+
 	if (gmap_is_shadow(gmap))
 		return;
 	if (start >= 1UL << 31)
diff --git a/arch/s390/kvm/trace-s390.h b/arch/s390/kvm/trace-s390.h
index 6f0209d45164..9ac92dbf680d 100644
--- a/arch/s390/kvm/trace-s390.h
+++ b/arch/s390/kvm/trace-s390.h
@@ -333,6 +333,29 @@  TRACE_EVENT(kvm_s390_airq_suppressed,
 		      __entry->id, __entry->isc)
 	);
 
+/*
+ * Trace point for gmap notifier calls.
+ */
+TRACE_EVENT(kvm_s390_gmap_notifier,
+	    TP_PROTO(unsigned long start, unsigned long end, unsigned int shadow),
+	    TP_ARGS(start, end, shadow),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned long, start)
+		    __field(unsigned long, end)
+		    __field(unsigned int, shadow)
+		    ),
+
+	    TP_fast_assign(
+		    __entry->start = start;
+		    __entry->end = end;
+		    __entry->shadow = shadow;
+		    ),
+
+	    TP_printk("gmap notified (start:0x%lx end:0x%lx shadow:%d)",
+		      __entry->start, __entry->end, __entry->shadow)
+	);
+
 
 #endif /* _TRACE_KVMS390_H */