This adds static markers for dtrace, which are also usable
by systemtap. Additionally it adds a tapset for systemtap
that makes it easier to use the static markers.
These are enabled by default.
This initial set of probes is rather limited:
* allocation and free using g_malloc & co
* allocation and free using g_slice
* gquark name tracking (useful for converting quarks to strings in probes)
Notes on naming:
Its traditional with dtrace to use probe names with dashes as
delimiter (slice-alloc). Since dashes are not usable in identifiers
the C code uses double underscores (slice__alloc) which is converted
to dashes in the UI. We follow this for the shared lowlevel probe
names.
Additionally dtrace supports putting a "provider" part in the probe
names which is essentially a namespacing thing. On systemtap this
field is currently ignored (but may be implemented in the future), but
this is not really a problem since in systemtap the probes are
specified by combining the solib file and the marker name, so there
can't really be name conflicts.
For the systemtap tapset highlevel probes we instead use names that
are systemtapish with single dashes as separators.
https://bugzilla.gnome.org/show_bug.cgi?id=606044
Fixup for commit 133f66538d which
duplicated the contents of most of the migration documentation by
splitting it out into separate files but keeping the original file
intact (with a rename).
This removes the duplicated content from the renamed file.
This uncovered a bug in name watching if the name wasn't activatable.
Also provoked the need for on_connection variants of g_bus_watch_name
(added g_bus_watch_proxy's variant as well).
This makes it possible to use the cached properties mechanism even if
constructing the proxy with the DO_NOT_LOAD_PROPERTIES flag.
This is useful for cases where you obtain the and track object
properties out-of-band. For example, in udisks, the plan is to have
something like this
Manager.GetObjects (out ao paths, out aa{sa{sv}} all_properties);
Manager.ObjectAdded (o path, a{sa{sv}} all_properties);
Manager.ObjectChanged (o path, a{sa{sv}} all_properties);
Manager.ObjectRemoved (o path, a{sa{sv}} all_properties);
E.g. the first GetObjects() call will return *all* data about *all*
exported objects. Further, this way a client will only need to listen
these three signals (three AddMatch) on the Manager object and it will
never need to do GetAll() etc (e.g. can use DO_NOT_LOAD_PROPERTIES).
(Of course this only works if the client is interested in all
objects... while this is true for udisks it is generally not true for
other D-Bus services).
Also use expected_interface to check for programming errors.
Lots of people been suggesting this. We still use MethodInvocation /
method_invocation for handling incoming method calls so use call()
instead of invoke_method() helps to separate the client and server
facilities. Which is a good thing(tm).
