Re: [PATCH v4 1/6] perf tools: Derive trigger class from auxtrace_snapshot

From: Jiri Olsa
Date: Mon Apr 18 2016 - 09:45:52 EST


On Mon, Apr 18, 2016 at 06:32:08AM +0000, Wang Nan wrote:
> Use 'trigger' to model operations which need to be executed when
> an event (a signal, for example) is observed.
>
> States and transits:
>
> OFF--(on)--> READY --(toggle)--> TOGGLED --(process)--> PROCESSING
> ^ | |
> | | |
> | (ready) (ready)
> | | |
> \__________________/______________________/
>
> is_toggled and is_ready are two key functions to query the state of
> a trigger. is_toggled means the event already happen; is_ready means the
> trigger is waiting for the event.
>
> 'PROCESSING' represents a state the event happens and be observed, and
> the processing is on the way so can't accept a new event immediately.

hum, I must be missing something.. but I dont see how you're
using this state except for smal window within:

if (auxtrace_snapshot_is_toggled()) {
-> auxtrace_snapshot_process();
if (!auxtrace_snapshot_is_error())
-> record__read_auxtrace_snapshot(rec);

but no other place queries or depends on this state

also the switch_output code does not seem to use this transition at all

thanks,
jirka