SystemTap Instruction Tracing Proposal

[Dave Nomura <dcnltc at us dot ibm dot com>]

The data produced by an instruction tracing tool is used by other 
performance analysis tools to detect pipeline performance problems and 
for tuning highly optimized code. We feel that having instruction 
tracing integrated with SystemTap would make it more widely available in 
various Linux distributions.

Requirements
o support both single step and branch tracing modes
o single step traces would also collect load/store trace data
o ability to trace user code including system calls into kernel space
o support for tracing single and mulitiple processes
o ability for user to turn on/off tracing for specific pid or group of pids
o pluggable post processing component to allow formatting of trace data 
for a variety of performance analysis tools

We have been developing a somewhat brute-force SystemTap script based on 
the Performace Inspector ITRACE tool to familiarize ourselves with 
SystemTap and to explore some of the issues/problems that may need 
further SystemTap support.
We are making this proposal as a result of this prototyping work and the 
discussions we've had with some members of the SystemTap community.

Is there sufficient interest in the SystemTap community in having an 
instruction tracing capability as described above to warrant futher 
discussion and investigation?


--
Dave Nomura
LTC Linux Power Toolchain