Messages in this thread | | | Date | Fri, 5 Dec 2008 07:28:22 -0500 | From | Mathieu Desnoyers <> | Subject | Re: [ltt-dev] trace a futex |
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* Peter Zijlstra (peterz@infradead.org) wrote: > > FWIW, the ftrace infrastructure has on many an occasion (even before it > was called ftrace and specific to -rt) helped in debugging and fixing > futex races. >
Hrm, I'm not sure futex races is the key aspect of interest here. Knowing which amount of pthread mutex lock calls ends up calling the scheduler looks a bit more like the topic brought by this particular use-case. Therefore, correlating the information from the nptl with the kernel information would be useful.
Is lockdep called when a futex is taken ? Should we add instrumentation (tracepoints) to futex.c ? If yes, was there specific instrumentation you used with ftrace that should be added ?
Mathieu
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