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Diffstat (limited to 'libraries/libprof/README.txt')
-rw-r--r-- | libraries/libprof/README.txt | 65 |
1 files changed, 60 insertions, 5 deletions
diff --git a/libraries/libprof/README.txt b/libraries/libprof/README.txt index 2df8b96..da138c2 100644 --- a/libraries/libprof/README.txt +++ b/libraries/libprof/README.txt @@ -1,6 +1,61 @@ -Copied from https://github.com/ErichStyger/mcuoneclipse.git, -directory Examples/KDS/FRDM-K64F120M/FRDM-K64F_Profiling/Profiling, -commit 9b7eedddd8b24968128582aedc63be95b61f782c, -dated Mon Jan 9 16:56:17 2017 +0100. -(This is in turn adapted from Cygwin, and can be found in newlib distributions.) +Profiling the Cryptech Alpha +============================ +Origin +------ + +This code was copied from https://github.com/ErichStyger/mcuoneclipse.git, +directory Examples/KDS/FRDM-K64F120M/FRDM-K64F_Profiling/Profiling, commit +9b7eedddd8b24968128582aedc63be95b61f782c, dated Mon Jan 9 16:56:17 2017 +0100. + +References +---------- + +I recommend reading both of these to understand how the profiling code works. + +[1]: https://mcuoneclipse.com/2015/08/23/tutorial-using-gnu-profiling-gprof-with-arm-cortex-m/ +"Tutorial: Using GNU Profiling (gprof) with ARM Cortex-M" + +[2]: http://bgamari.github.io/posts/2014-10-31-semihosting.html +"Semihosting with ARM, GCC, and OpenOCD" + +How to build +------------ + +From the top level, run + + make DO_PROFILING=1 hsm + +By default, all code is profiled, *except* the profiling code itself, +because that would cause fatal recursion. + +How to run +---------- + +You need to start OpenOCD on the host, and enable semihosting, at least +before you try to use it as a remote file system. + +I recommend executing the following in the projects/hsm directory, so that +gmon.out ends up in the same directory as hsm.elf. + +Start OpenOCD: + + $ openocd -f /usr/share/openocd/scripts/board/stm32f4discovery.cfg & + +Connect to OpenOCD: + + $ telnet localhost 4444 + +In the OpenOCD console, enable semihosting: + + > arm semihosting enable + +In the CLI, type `profile start`, then start the unit test or whatever +will be exercising the hsm. Afterwards, in the CLI, type `profile stop`. + +After invoking `profile stop`, it takes almost 2 minutes to write gmon.out +over OpenOCD to the host. + +In the projects/hsm directory, run gprof to analyse the gmon.out file: + + $ gprof hsm.elf >gprof.txt |