On Fri, 14 Jul 2017 11:22:51 +0530 Pratyush Anand <panand@xxxxxxxxxx> wrote: > Hi Felipe, > > On Friday 09 June 2017 03:58 PM, Felipe Balbi wrote: > > Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> writes: > > > >> Allow for ftrace data to be exported over a USB Gadget > >> Controller. With this, we have a potentially very fast pipe for > >> transmitting ftrace data to a Host PC for further analysis. > >> > >> Note that in order to decode the data, one needs access to kernel > >> symbols in order to convert binary data into function names and what > >> not. > >> > >> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> > >> --- > >> > >> I wanted to take this through the gadget tree, but there is a > >> dependency with a previous patch of mine adding and extra argument to > >> the ->write() function. Hoping someone else will take it. > > > > just as an extra note here. In order for this to be really useful, it > > would be nice to be able to control what is going to be traced over USB > > Probably you will also need to export *atleast* symbol information. In future, > if this framework is extended to export tracepoint/kprobe/uprobe event data, > then the information like event format etc will also need to be exported. > > What tool do you use on host machine in order to extract information from this > exported target ring buffer data? > IMHO, standard tools like trace-cmd will not be able to use it as it is. > Have you looked at how trace-cmd does network transfers? Perhaps this can do something similar. I'm also working on having trace-cmd work through sockets for guest to host tracing. See trace-cmd listen. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
