Hi,

On Thu Jan 31, 2013 at 10:56:57 +0400, óÅÒÇÅÊ çÒÅÈÏ× wrote:

1. Is there any way to know on the receive side who had sent the IPC

we have catched with l4_ipc_wait()? One of the ways if to enable IPC logging in JDB. But the problem is that trace usually consist of several thousands of IPCs and I need only one. Filtering helps a bit, but still it takes much more time to find needed info.

l4_ipc_wait() has the label which identifies the ipc-gate through which the IPC came. However, this does not identify the sender (thread) in case multiple threads are using the same ipc-gate. To help with the trace, user-space can also add trace entries via fiasco_tbuf_log(_3val) which might help identifying specific sequences. enter_kdebug is also popular to stop execution and enter jdb.

2. According to the description of l4_ipc_reply_and_ipc_wait() in

header file: "A message is sent to the previous caller using the implicit reply capability. Afterwards the invoking thread waits for a message from any source." The question is what events/things/whatever updates this implicit reply capability and what will happen if this capability is invalid?

It will be set for ipc-call operation, so that an answer can come back. Invalid would mean an ipc-reply operation would return with an error.

And one more general question. Is there any documentation on JDB?

There's the jdb manual: http://os.inf.tu-dresden.de/fiasco/doc.html

Adam