Re: [PATCH v4 2/7] kernel-shark-qt: Add Plugin event handlers to session.

["Yordan Karadzhov (VMware)" <y.karadz@xxxxxxxxx>]

On 20.09.2018 06:24, Steven Rostedt wrote:
> > static size_t get_records(struct kshark_context *kshark_ctx,
> >   			  struct rec_list ***rec_list, enum rec_type type)
> >   {
> > +	struct kshark_event_handler *evt_handler;
> >   	struct event_filter *adv_filter;
> >   	struct kshark_task_list *task;
> >   	struct tep_record *rec;
> > @@ -608,6 +618,17 @@ static size_t get_records(struct kshark_context *kshark_ctx,
> >   
> >   				entry = &temp_rec->entry;
> >   				kshark_set_entry_values(kshark_ctx, rec, entry);
> > +
> > +				/* Execute all plugin-provided actions (if any). */
> > +				evt_handler = kshark_ctx->event_handlers;
> > +				while ((evt_handler = find_event_handler(evt_handler,
> > +									 entry->event_id))) {
> > +					evt_handler->event_func(kshark_ctx, rec, entry);
> > +
> > +					if ((evt_handler = evt_handler->next))
> Please break the above if, to remove the assignment. It's just easier
> to read. That is:
>
> 					event_handler = event_hanndler->next;
> 					if (event_handler)
> > +						entry->visible &= ~KS_PLUGIN_UNTOUCHED_MASK;
> > +				}
> > +

Actually this is a bug (typo). I meant to have

					evt_handler = evt_handler->next;
					if (!evt_handler)
						entry->visible &= ~KS_PLUGIN_UNTOUCHED_MASK;

This way the KS_PLUGIN_UNTOUCHED flag gets unset only once and it is 
guaranteed that the value of the bit cannot be changed by the plugin 
callback function.

Thanks!
Yordan


> >   				pid = entry->pid;
> >   				/* Apply event filtering. */
> >   				ret = FILTER_MATCH;