On Fri, Oct 07, 2016 at 03:59:07PM +0200, Markus Armbruster wrote: > "Daniel P. Berrange" <berra...@redhat.com> writes: > > > Allow tracing of the operation of visitors > > > > Signed-off-by: Daniel P. Berrange <berra...@redhat.com> > > --- > > Makefile.objs | 1 + > > qapi/qapi-visit-core.c | 27 +++++++++++++++++++++++++++ > > qapi/trace-events | 33 +++++++++++++++++++++++++++++++++ > > 3 files changed, 61 insertions(+) > > create mode 100644 qapi/trace-events > > > > diff --git a/Makefile.objs b/Makefile.objs > > index a8e0224..b3e8aef 100644 > > --- a/Makefile.objs > > +++ b/Makefile.objs > > @@ -160,3 +160,4 @@ trace-events-y += target-s390x/trace-events > > trace-events-y += target-ppc/trace-events > > trace-events-y += qom/trace-events > > trace-events-y += linux-user/trace-events > > +trace-events-y += qapi/trace-events > > diff --git a/qapi/qapi-visit-core.c b/qapi/qapi-visit-core.c > > index 55f5876..bfcb276 100644 > > --- a/qapi/qapi-visit-core.c > > +++ b/qapi/qapi-visit-core.c > > @@ -19,10 +19,12 @@ > > #include "qapi/qmp/qerror.h" > > #include "qapi/visitor.h" > > #include "qapi/visitor-impl.h" > > +#include "trace.h" > > > > void visit_complete(Visitor *v, void *opaque) > > { > > assert(v->type != VISITOR_OUTPUT || v->complete); > > + trace_visit_complete(v, opaque); > > Trace after or before checking the precondition? Preferences, anyone?
I'm ambivalent, as the assert will crash you either way so whether you get a trace event just before the crash seems mostly irrelevant to me - the abort stack trace is what you'll use to diagnose the crash. > > > if (v->complete) { > > v->complete(v, opaque); > > } > > @@ -30,6 +32,7 @@ void visit_complete(Visitor *v, void *opaque) > > > > void visit_free(Visitor *v) > > { > > + trace_visit_free(v); > > if (v) { > > v->free(v); > > } > > @@ -40,6 +43,7 @@ void visit_start_struct(Visitor *v, const char *name, > > void **obj, > > { > > Error *err = NULL; > > > > + trace_visit_start_struct(v, name, obj, size); > > if (obj) { > > assert(size); > > assert(!(v->type & VISITOR_OUTPUT) || *obj); > > @@ -53,6 +57,7 @@ void visit_start_struct(Visitor *v, const char *name, > > void **obj, > > > > void visit_check_struct(Visitor *v, Error **errp) > > { > > + trace_visit_check_struct(v); > > if (v->check_struct) { > > v->check_struct(v, errp); > > } > > @@ -60,6 +65,7 @@ void visit_check_struct(Visitor *v, Error **errp) > > > > void visit_end_struct(Visitor *v, void **obj) > > { > > + trace_visit_end_struct(v, obj); > > v->end_struct(v, obj); > > } > > > > @@ -69,6 +75,7 @@ void visit_start_list(Visitor *v, const char *name, > > GenericList **list, > > Error *err = NULL; > > > > assert(!list || size >= sizeof(GenericList)); > > + trace_visit_start_list(v, name, list, size); > > v->start_list(v, name, list, size, &err); > > if (list && (v->type & VISITOR_INPUT)) { > > assert(!(err && *list)); > > @@ -79,11 +86,13 @@ void visit_start_list(Visitor *v, const char *name, > > GenericList **list, > > GenericList *visit_next_list(Visitor *v, GenericList *tail, size_t size) > > { > > assert(tail && size >= sizeof(GenericList)); > > + trace_visit_next_list(v, tail, size); > > return v->next_list(v, tail, size); > > } > > > > void visit_end_list(Visitor *v, void **obj) > > { > > + trace_visit_end_list(v, obj); > > v->end_list(v, obj); > > } > > > > @@ -95,6 +104,7 @@ void visit_start_alternate(Visitor *v, const char *name, > > > > assert(obj && size >= sizeof(GenericAlternate)); > > assert(!(v->type & VISITOR_OUTPUT) || *obj); > > + trace_visit_start_alternate(v, name, obj, size, promote_int); > > if (v->start_alternate) { > > v->start_alternate(v, name, obj, size, promote_int, &err); > > } > > @@ -106,6 +116,7 @@ void visit_start_alternate(Visitor *v, const char *name, > > > > void visit_end_alternate(Visitor *v, void **obj) > > { > > + trace_visit_end_alternate(v, obj); > > if (v->end_alternate) { > > v->end_alternate(v, obj); > > } > > @@ -113,6 +124,7 @@ void visit_end_alternate(Visitor *v, void **obj) > > > > bool visit_optional(Visitor *v, const char *name, bool *present) > > { > > + trace_visit_optional(v, name, present); > > if (v->optional) { > > v->optional(v, name, present); > > } > > @@ -127,6 +139,7 @@ bool visit_is_input(Visitor *v) > > void visit_type_int(Visitor *v, const char *name, int64_t *obj, Error > > **errp) > > { > > assert(obj); > > + trace_visit_type_int(v, name, obj); > > v->type_int64(v, name, obj, errp); > > } > > > > @@ -151,6 +164,7 @@ void visit_type_uint8(Visitor *v, const char *name, > > uint8_t *obj, > > Error **errp) > > { > > uint64_t value = *obj; > > + trace_visit_type_uint8(v, name, obj); > > visit_type_uintN(v, &value, name, UINT8_MAX, "uint8_t", errp); > > *obj = value; > > } > > Putting the trace in the middle of the "value = *obj; > visit_type_uintN(v, &value, ...); *obj = value" pattern makes it less > visible. > > Preserving the pattern requires replacing the initializer by an > assignment: > > uint64_t value; > > trace_visit_type_uint8(v, name, obj); > value = *obj; > visit_type_uintN(v, &value, name, UINT8_MAX, "uint8_t", errp); > *obj = value; > > Looks slightly more legible to me. What do you think? I'm fine with whatever you prefer. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :|