Hi,
the top options for me are:
- restrict to userspace / kernelspace / both - restrict to one process, or an address range (whatever perf for Intel PT offers here - if it has an option to restrict trace to a specific DSO or the main executable, that would be ideal... would be nice if it worked with ASLR) - cycle accurate vs. non cycle accurate: I almost always use cycle-accurate but we must give people the option to disable it in case of overflow or buffer size problems - sync frequency (however good the default is, you might want to change it) - branch broadcasting / disable return stack - not generally needed, but useful when diagnosing a broken decode due to JIT etc. (default should be return stack enabled and branch broadcast disabled).
I think timestamp and 4-byte CONTEXTIDR should be enabled always... although you could have experts-only options to disable them.
The simpler the better really!
Al
-----Original Message----- From: Mathieu Poirier [mailto:mathieu.poirier@linaro.org] Sent: 14 September 2015 15:53 To: Al Grant; Mike Leach Cc: coresight@lists.linaro.org Subject: Coresight configuration options
Al and Mike,
With the work on coresight/Perf integration proceeding as planned the time to start looking at how configuration parameters can be conveyed to the tracers using the perf cmd tool is fast approaching, and that's where I need to pick your brain.
In your opinion and based on your experience with coresight, what are the 5 most wanted configuration options we need to start with?
The question could also be thought of as the 5 most common thing people configure when using coresight. Finding a way to give access to all the configuration option of a tracer via cmd line won't be easy but I believe it can be done. If we find a way to address the most commonly used options as an starting point the rest should come easily.
Please think about it and get back to me. My plan is to get the discussion going with the perf maintainer about the best way to proceed sometime this week or the next, depending on schedule.
Thanks, Mathieu
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