On Thu, Oct 23, 2014 at 05:16:38PM +0200, Justus Winter wrote: > this patch series adds introspection and tracing facilities to the > Hurd servers using libports. This isn't ready yet, but I'd like to > give everyone a chance to complain early on. Some notes: > > * I use Machs `Inherited Ports' mechanism to install a receive right > at a well-known location to serve introspection requests. This is > by choice orthogonal to the usual mechanism used in the Hurd, as I > want it to be as universal as possible (e.g. I want to be able to > use it on the proc server).
I was initially not sure about that, since I prefer such things to be explicit, but it's a very pragmatic choice that I approve. > * Servers can label port buckets and classes, and install a function > that creates a human-readable description of an object. This > information is then presented to the user doing portinfo > --query-process, a feature that is hinted to by a #if 0ed option in > portinfo.c. Do we agree that, when saying "install a function", you mean providing a RPC to answer introspection requests ? In which case this would mean no reply if e.g. a deadlock occurs (although your work on reference counting should make deadlocks less frequent). Not flaming here, just making sure. > * rpctrace can now attach to cooperating servers that just relay > messages to the tracing process. To that end, a footer is attached > to the message to preserve original remote and local port, all > rights are turned into mere names, and the msgt_deallocate flag is > cleared so that out-of-band data isn't deallocated when we resend > the message. > > * A new library, libintrospection, handles the introspection port > registration and lookup, and the message wrapping/unwrapping. Well, one big step towards lsof-like tools and easier debugging. As usual, very good job :). -- Richard Braun
