On Wed, 2012-05-16 at 15:08 -0300, Arnaldo Carvalho de Melo wrote: > Em Wed, May 16, 2012 at 12:58:23PM -0400, Steven Rostedt escreveu: > > On Wed, 2012-05-16 at 11:59 -0300, Arnaldo Carvalho de Melo wrote: > > > Was the kernel trace events infrastructure designed with that in > > > mind? I.e. cross analysis? I must be missing something here, still > > > ENOCOFFEE :-\ > > > > Yes, the libparsevents library was design for this from day one. That's > > why trace-cmd data file can be run on an ARM and read on x86, or PPC, or > > whatever. I did all my development testing against 32bit, 64bit and big > > and little endian. This was the case from the beginning. > > I need to look at the code, but how does it do this? Copy the relevant > /sys/kernel/debug/events formats in the header and then instead of > looking at /sys/... look at those?
It does copy the events from .../debug/tracing/events. But it does cheat about the bits. To determine the size, it looks at /sys/kernel/debug/tracing/events/header_page and the field of "commit". On 32bit machines, that's 4bytes, and on 64bit, that's 8 bytes. For endianess, that is calculated on the machine that the recording is running on and stored in the file. The parse-events structure has a way to record the endianess and long size, for later retrieval. > > Does it still copy /proc/kallsyms? Yes it does. -- Steve _______________________________________________ linaro-dev mailing list linaro-dev@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-dev
