Messages in this thread | | | Subject | Re: [PATCH] tracing: Add task activate/deactivate tracepoints | From | Peter Zijlstra <> | Date | Mon, 31 May 2010 10:54:59 +0200 |
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On Mon, 2010-05-31 at 10:12 +0200, Peter Zijlstra wrote: > On Mon, 2010-05-31 at 10:00 +0200, Ingo Molnar wrote: > > > > > > NAK, aside from a few corner cases wakeup and sleep are the important > > > points. > > > > > > The activate and deactivate functions are implementation details. > > > > Frederic, can you show us a concrete example of where we dont know what is > > going on due to inadequate instrumentation? Can we fix that be extending the > > existing tracepoints? > > Right, so a few of those corner cases I mentioned above are things like > re-nice, PI-boosts etc.. Those use deactivate, modify task-state, > activate cycles. so if you want to see those, we can add an explicit > tracepoint for those actions. > > An explicit nice/PI-boost tracepoint is much clearer than trying to > figure out wth the deactivate/activate cycle was for.
Another advantage of explicit tracepoints is that you'd see them even for non-running tasks, because we only do the deactivate/activate thingy for runnable tasks.
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