summaryrefslogtreecommitdiff
path: root/microkernel/genode
diff options
context:
space:
mode:
authorThomas Schwinge <tschwinge@gnu.org>2012-08-07 23:25:26 +0200
committerThomas Schwinge <tschwinge@gnu.org>2012-08-07 23:25:26 +0200
commit2603401fa1f899a8ff60ec6a134d5bd511073a9d (patch)
treeccac6e11638ddeee8da94055b53f4fdfde73aa5c /microkernel/genode
parentd72694b33a81919368365da2c35d5b4a264648e0 (diff)
IRC.
Diffstat (limited to 'microkernel/genode')
-rw-r--r--microkernel/genode/rpc.mdwn65
1 files changed, 65 insertions, 0 deletions
diff --git a/microkernel/genode/rpc.mdwn b/microkernel/genode/rpc.mdwn
new file mode 100644
index 00000000..4f68a9f6
--- /dev/null
+++ b/microkernel/genode/rpc.mdwn
@@ -0,0 +1,65 @@
+[[!meta copyright="Copyright © 2012 Free Software Foundation, Inc."]]
+
+[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
+id="license" text="Permission is granted to copy, distribute and/or modify this
+document under the terms of the GNU Free Documentation License, Version 1.2 or
+any later version published by the Free Software Foundation; with no Invariant
+Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
+is included in the section entitled [[GNU Free Documentation
+License|/fdl]]."]]"""]]
+
+
+# IRC, freenode, #hurd, 2012-07-20
+
+ <braunr> for the curious, genode has a very interesting way to provide IPC
+ <braunr> i think they're on the right path at least (synchronous rpc,
+ shared memory, signals, no IDL)
+ <braunr> (i just don't like their choosing C++ at the system core)
+ <kilobug> braunr: hum, how do you write the rpc if there is no IDL ?
+ <kilobug> braunr: in a dynamic language like Python or Ruby, you can have
+ "transparent" RPC with no IDL, but in a language like C or C++ ?
+ <kilobug> when you call them I mean
+ <braunr> kilobug: they call this dynamic marshalling based on C++ streams
+ <braunr> http://genode-labs.com/publications/dynrpc-2007.pdf
+ <kilobug> sounds quite ugly to use :s but that may because I'm not fond of
+ C++ itself ;)
+ <braunr> same for me
+ <braunr> they say inheritance in RPC interfaces is "a must"
+ <braunr> makes me skeptical
+ <braunr> other than that, it's very promising
+ <kilobug> from the caller side, having the RPC appearing to be normal
+ function calls (like you do with Mig or Corba) is quite pleasant, even if
+ writing IDL is burdersome, you write IDL only once while calling RPC is
+ done very often
+ <braunr> oh but they have that as well
+ <braunr> there is just an additional, thin layer of hand written code to
+ provide that
+ <kilobug> ok
+ <braunr> basically, interfaces are C++ virtual classes, which are then
+ inherited in client and server classes
+ <braunr> (although they're changing that with recursive templates)
+ <braunr> but i really like to idea of not relying on an IDL
+ <kilobug> recursive templates :s
+ <braunr> yeah :>
+ <braunr> must be some tricky code, but i guess once it's there, it must be
+ practical
+ <braunr> see
+ http://genode.org/documentation/release-notes/11.05#New_API_for_type-safe_inter-process_communication
+ <braunr> they also added typed capabilities, but i don't really like that
+ idea
+ <antrik> braunr: shared memory for what?
+ <braunr> antrik: for uh.. sharing ? :)
+ <braunr> antrik: these systems don't provide ipc primitives able to share
+ memory directly
+ <braunr> messages are always copied (although zero copy can be used)
+ <braunr> so sharing must be done separately
+ <antrik> hm... I realise that I have no idea how the map operation in L4 is
+ actually done...
+ <braunr> iirc, privileged threads handle that
+ <antrik> I guess you have to explicitly map before an RPC and revoke
+ afterwards, which is some overhead...
+ <braunr> so i guess it's separated as well
+ <braunr> i have one question in mind for now, maybe you can help me with
+ that :
+
+[[open_issues/synchronous_ipc]].