Hi Johannes, If you have the sources for marshalling conveniently laying around, please share, I'd like to have a look at them.
Thanks, Menno On 21-03-16 17:01, Johannes Schlatow wrote: > Hi Menno, > > On Mon, 21 Mar 2016 12:52:22 +0100 > Menno Valkema <menno.gen...@gmail.com> wrote: > >> Hi Johannes, >> >> This is great. Currently we're trying to accomplish a similar thing for >> RPC calls and Signals. The approach with statically configured proxies >> you take, also made most sense to us, which is what we did for RPC >> calls, and we're now trying to use it for Signals. Combined with your >> work it seems together we made the first steps towards distributed use >> of the fundamental IPC mechanisms provided by Genode (shared memory, >> rpc, and signals). >> >> For RPC calls we took a similar approach using a client_proxy and a >> server_proxy. Say we have a session called abc_session this is how the >> components collaborate: >> 1) Abc Rpc client connects to a client_proxy which behaves like a >> abc_session/session_component >> 2) The client_proxy marshalls the commands into command structures with >> opcodes and arguments, and forwards these over a nic connection. >> 3) server_proxy receives the commands over a nic connection, un-marshals >> the commands, and forwards the requests to the server while behaving as >> a abc_session client. >> 4) the server handles the request, and returns. >> 5) return value is forwarded to the client in a similar way the commands >> were transmitted. >> >> Where we both have some form of serialized commands (in your case it's >> handled by the ip backend with an enum identifying the action is being >> sent over), we choose, for now, not to specify any sort of >> transportation mechanism except a bare nic session, and send raw data >> over nic sessions. In case we need an ip layer, we plan to move this in >> a separate component which knows how to handle ip, ipsec or some other >> protocol. However, I like the idea of your implementation to use various >> back-ends which handle different transportation types. >> >> Some challenges we're still looking into are: >> - Manual marshalling. Right now we marshall the rpc calls manually. >> Genode already has a great marshalling mechanism in place, however I >> didn't manage to re-use this, so for now I do it by hand. This seems >> like a bit of a waste, so in a later stage I hope to look into this again. > > I also started with a generic proxy implementation for RPC some time ago and > did make some progress on the marshalling. However, I dismissed the idea as > RPC over a network didn't appeal to me as a very good idea, especially when > distributed capabilities are required. > Nevertheless, I might have some code buried in my repositories. Let me know > if you're interested in that. > >> - Cross CPU architecture usage of arguments. How to handle integer >> arguments or structs with integer arguments between big/little endian >> architectures, or systems with a different notion of word-lengths and >> struct alignment? >> - We're still working on Signals. >> - Routing. Presently we statically configure how the client-proxy and >> the server-proxy are connected. It would be better if we had more >> flexibility here, like what's now being provided by init. >> - Capabilities. It would be great to have some sort of distributed >> capability system to have stricter control over who talks to who. >> >> Regards, >> Menno >> >> PS. I went through you source code to see how you implemented things, >> and it's quite clear what's going on. However when I tried to run the >> server by typing 'make run/test-remoterom_backend_nic_ip_server' some >> methods being called seemed to be missing (calculate_checksum for >> example), and the compiler exited with an error. It seems some of the >> work is not in the github repository yet? > > Oh, sorry. I forgot to mention that this requires some modifications of the > Ipv4_packet class, see: > https://github.com/genodelabs/genode/pull/1915 > > ------------------------------------------------------------------------------ > Transform Data into Opportunity. > Accelerate data analysis in your applications with > Intel Data Analytics Acceleration Library. > Click to learn more. > http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140 > _______________________________________________ > genode-main mailing list > genode-main@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/genode-main > ------------------------------------------------------------------------------ Transform Data into Opportunity. Accelerate data analysis in your applications with Intel Data Analytics Acceleration Library. Click to learn more. http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140 _______________________________________________ genode-main mailing list genode-main@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/genode-main
