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@@ -172,3 +172,29 @@ Charging
controlled charging that Rockbox can't affect.)
...
+
+Profiling
+
+ Rockbox contains a profiling system which can be used to monitor call count
+ and time in function for a specific set of functions on a single thread.
+
+ To use this functionality:
+ 1) Configure a developer build with profiling support.
+ 2) Make sure that the functions of interest will be compiled with the
+ PROFILE_OPTS added to their CFLAGS
+ 3) On the same thread as these functions will be run, surround the relevent
+ running time with calls to profile_thread and profstop. (For codecs,
+ this can be done in the codec.c file for example)
+ 4) Compile and run the code on the target, after the section to be profiled
+ exits (when profstop is called) a profile.out file will be written to
+ the player's root.
+ 5) Use the tools/profile_reader/profile_reader.pl script to convert the
+ profile.out into a human readable format. This script requires the
+ relevent map files and object (or library) files created in the build.
+ (ex: ./profile_reader.pl profile.out vorbis.map libTremor.a 0)
+
+ There is also a profile_comparator.pl script which can compare two profile
+ runs as output by the above script to show percent change from optimization
+
+ profile_reader.pl requires a recent binutils that can automatically handle
+ target object files, or objdump in path to be the target-objdump.