Cough ... cough ... I did not notice TRACEME() 😀 New code does not support it, should I add back?
On Thu, Nov 5, 2015 at 10:52 AM, Barret Rhoden <[email protected]> wrote: > On 2015-10-31 at 10:28 "'Davide Libenzi' via Akaros" > <[email protected]> wrote: > > But the timers have no use alone. There is nothing that uses them, if > > the profiler is not running. > > The separation between the timer and the start/stop was done > intentionally. > > Here's the rationale from when that code was written: > > commit 383648aa099a3974b397cf81d1a82969bf7814fc > Author: Barret Rhoden <[email protected]> > Date: Tue Dec 9 22:44:37 2014 -0800 > > Per-cpu timer control for oprofile sampling > > To use oprof now, you need to set the timer, then enable the profiling. > If/when we add other tracers that can be turned on and off, we'll > continue to use this model: set the collection of things to trace, then > start them all at once. > > If you don't have the timers turned on, but you run opstart, other > traces, such as TRACE_ME and whatnot (like perhaps writing traces from > userspace via kpoprofile) will still be collected. > > I don't have a control for various TRACE_MEs yet. Maybe we can add one > (like printx). > > Some examples: > > To turn on the timer on core 0. This turns on an alarm/IRQ: > > $ echo optimer 0 on > /prof/kpctl > > Then start the actual profiling/collection: > > $ echo opstart > /prof/kpctl > > To stop collecting: > > $ echo opstop > /prof/kpctl > > To turn off all the timers: > > $ echo optimer all off > /prof/kpctl > > Oh, and you can adjust the timer period if you like. Default is 1ms. > > $ echo optimer period 1000 > /prof/kpctl (period is in usec) > > -- > You received this message because you are subscribed to the Google Groups > "Akaros" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Akaros" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. For more options, visit https://groups.google.com/d/optout.
