Hi Tom, On Tue, 18 Sep 2018 14:16:43 -0500 Tom Zanussi <[email protected]> wrote:
> Hi Masami, > > On Wed, 2018-09-19 at 03:54 +0900, Masami Hiramatsu wrote: > > Hi Tom, > > > > On Mon, 10 Sep 2018 14:10:46 -0500 > > Tom Zanussi <[email protected]> wrote: > > > > > From: Tom Zanussi <[email protected]> > > > > > > Add a 'trace(synthetic_event_name, params)' alternative to > > > synthetic_event_name(params). > > > > > > Currently, the syntax used for generating synthetic events is to > > > invoke synthetic_event_name(params) i.e. use the synthetic event > > > name > > > as a function call. > > > > > > Users requested a new form that more explicitly shows that the > > > synthetic event is in effect being traced. In this version, a new > > > 'trace()' keyword is used, and the synthetic event name is passed > > > in > > > as the first argument. > > > > Hmm, what is the advantage of adding this new form? > > > > There's no real advantage other than user preference - Namhyung thought > that since the event-name-as-function-call actions are all defined as > ACTION_TRACE, there should also be an explicit 'trace' action. Ah, got it. Would this needs documentation and testcase update too? > > So I added it as alternative syntax - the event-name-as-function-call > form remains unchanged. > > By the way, I also have a patch implementing your alternative syntax > change, where if you have only one handler, you can do away with the > explicit action.handler form e.g. > > # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-ts0: \ > onmax($wakeup_lat): \ > save(next_prio,next_comm,prev_pid,prev_prio,prev_comm):snapshot() \ Hmm, in this case, I think comma-connected syntax will be clearer when the action is kicked. onmax($wakeup_lat).save(next_prio,next_comm,prev_pid,prev_prio,prev_comm),snapshot() any thought? Thank you, > if next_comm=="cyclictest"' >> > /sys/kernel/debug/tracing/events/sched/sched_switch/trigger > > It just wasn't ready to go in with the v4 patches yet, so I decided > to submit it later as a follow-on. > > Tom > > > > Thanks, > > -- Masami Hiramatsu <[email protected]>
