Some comments only. On Sun Aug 17, 2014 at 11:03:07 +0000, Stark, Josef wrote: > in case anyone else is interested, here's what I found out so far: > So, as mentioned earlier, if ned wants to launch a certain task you specified, > ned does so indirectly by launching l4re and passing the name of the target > binary to l4re, > so l4re is basically the "parent" of the target task.
Parent maybe but not in the sense of a task because l4re runs in the very same task as the application. > As a parent, it seems that it receives all the capabilities you > specified in your lua config > for the target task, so doing IPC between l4re and _another_ task > seems much easier than expected. It's just because they share the same task. > I could successfully share a dataspace between a third task and l4re. > I used the config file from the shared_ds example, changed the client > sourcecode so that it only printed a "Hello" and then slept forever. > The part where it accesses the dataspace from the server was moved > (the part where it changes the ds content again was left out since I > did not need it) into l4re_kernel (the l4re binary), but is only > triggered if the name of the target binary was "ds_clnt", so that this > code wasn't executed multiple times (I know, this is _very_ hacky, but > remember, it should only serve as an example). > > And indeed, now l4re itself was able to print the content of the > dataspace. > (Accessing the ds from both l4re and its child also works, although > this wasn't my intention and I don't need it.) Ok, good but no suprise either :) > Instead of sharing a dataspace it should also be possible to do normal > IPC calls between l4re and a third task, e.g. to implement a central > temporary filesystem (which then can also be accessed from within > l4re) like mentioned in a previous mail. Yes. Basically, as you found out, with shared memory any thread/task that has access to this memory can access it and exchange data. Adam -- Adam [email protected] Lackorzynski http://os.inf.tu-dresden.de/~adam/ _______________________________________________ l4-hackers mailing list [email protected] http://os.inf.tu-dresden.de/mailman/listinfo/l4-hackers
