| Message ID | 20230510121822.546629-3-nrb@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: s390: add counters for vsie performance | expand |
On 10.05.23 14:18, Nico Boehr wrote: > 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> > --- > arch/s390/kvm/kvm-s390.c | 2 ++ > arch/s390/kvm/trace-s390.h | 23 +++++++++++++++++++++++ > 2 files changed, 25 insertions(+) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index ded4149e145b..e8476c023b07 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -3982,6 +3982,8 @@ 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..5dabd0b64d6e 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 */ > In the context of vsie, I'd have thought you'd be tracing kvm_s390_vsie_gmap_notifier() instead. This should work as well, as all notifier are called. Acked-by: David Hildenbrand <david@redhat.com>
Quoting David Hildenbrand (2023-07-27 09:41:51) > On 10.05.23 14:18, Nico Boehr wrote: > > 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> > > --- > > arch/s390/kvm/kvm-s390.c | 2 ++ > > arch/s390/kvm/trace-s390.h | 23 +++++++++++++++++++++++ > > 2 files changed, 25 insertions(+) > > > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > > index ded4149e145b..e8476c023b07 100644 > > --- a/arch/s390/kvm/kvm-s390.c > > +++ b/arch/s390/kvm/kvm-s390.c > > @@ -3982,6 +3982,8 @@ 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..5dabd0b64d6e 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 */ > > > > In the context of vsie, I'd have thought you'd be tracing > kvm_s390_vsie_gmap_notifier() instead. Right, I can change that if you / others have a preference for that.
>>> >>> #endif /* _TRACE_KVMS390_H */ >>> >> >> In the context of vsie, I'd have thought you'd be tracing >> kvm_s390_vsie_gmap_notifier() instead. > > Right, I can change that if you / others have a preference for that. > No strong opinion, just a thought.
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index ded4149e145b..e8476c023b07 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -3982,6 +3982,8 @@ 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..5dabd0b64d6e 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 */
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> --- arch/s390/kvm/kvm-s390.c | 2 ++ arch/s390/kvm/trace-s390.h | 23 +++++++++++++++++++++++ 2 files changed, 25 insertions(+)