The @udi field is not a static string, so any user of a NMPlatformLink
instance must make sure not to use the field beyond the lifetime of the
NMPlatformLink instance.
As we pass on the platform link instance during platform changed events,
this is hard to ensure for the subscriber of the signal -- because a
call back into platform could invalidate/modify the object.
Just not expose this field as part of the link instance. The few callers
who actually needed it should instead call nm_platform_get_uid(). With
that, the lifetime of the returned 'const char *' pointer is clearly
defined.
Use the event socket to request object via NLM_F_DUMP.
No longer use 'priv->nlh' socket to fetch objects.
Instead fetch them via the priv->nlh_event socket that also
provides asynchronous events when objects change.
That way, the events are in sync with our explicit requests
and we can directly use the events. Previously, the events were
only used to indicate that a refetch must happen, so that every
event triggered a complete dump of all addresses/routes.
We still use 'priv->nlh' to make synchronous requests such as
adding/changing/deleting objects. That means, after we send a
request, we must make sure that the result manifested itself
at 'nlh_event' socket and the platform cache.
That's why we sometimes still must force a dump to sync changes.
That could be improved by using only one netlink socket so that
we would wait for the ACK of our request.
While not yet perfect, this already significantly reduces the number of
fetches. Additionally, before, whenever requesting a dump of addresses
or routes (which we did much more often, search for "get_kernel_object for type"
log lines), we always dumped IPv4 and IPv6 together. Now only request
the addr-family in question.
https://bugzilla.gnome.org/show_bug.cgi?id=747985https://bugzilla.redhat.com/show_bug.cgi?id=1211133
Add a construct-only property NM_PLATFORM_REGISTER_SINGLETON to NMPlatform.
When set to TRUE, the constructor will self-register to nm_platform_setup().
The reason for this is that the _LOG() macro in NMLinuxPlatform logs the
self pointer if the instance is not the singleton instance.
During construction, we already have many log lines due to initialization
of the instance. These lines all end up qualified with the self pointer.
By earlier self-registering, printing the pointer value is omitted.
Yes, this patch is really just to prettify logging.
Switch platform caching implementation. Instead of caching libnl
objects, cache our own types.
Don't remove yet the now obsolete functions.
Advantage:
* Performance
- as we now cache our native NMPlatformObject instances, we no longer
have to convert libnl objects every time we access the platform
cache.
- for most cases, access is now O(1) because we can lookup the object
in a hash table. Note that ip4_address_get_all() still has to
create a copy of the result (O(n)), but as the caller is about to
use those elements, he cannot do better then O(n) anyway.
* We cache our own native types and have full control over them. We
cannot extend the libnl objects, which has many short-commings:
- _rtnl_addr_hack_lifetimes_rel_to_abs() to convert the timestamps
to absolute values (and back).
- hack_empty_master_iff_lower_up() would modify the internal flag,
but it looses the original value. That means, we can only hack
the state before putting a link into the cache, but we cannot revert
that change, when a slave in the cache changes state.
That was previously solved by always refetching the master when
a slave changed. Now we can re-evaluate the connected state
(DELAYED_ACTION_TYPE_MASTER_CONNECTED).
- we implement functions like equality, to-string as most suitable
for us. Before we needed hacks like nm_nl_object_diff(),
nm_nl_cache_search(), route_search_cache().
- we can extend our objects with exactly those properties we care,
and possibly additional properties that are not representable in
the libnl objects.
- we no longer cache RTM_F_CLONED routes and they get rejected early
on as we receive them.
- In the future, maybe it'd be interesting the make platform objects
immutable (and ref-counted) and expose them directly.
* Previous implementation did not order the refresh of objects but
called check_cache_items(). Now, those actions are delayed and
combined in an attempt to reduce the overall number of reloads.
Realize how expensive a check_cache_items() for addresses and routes
was: it would iterate all addresses/routes and call refresh_object().
The latter obtains a full dump of *all* objects again, and ignores
all but the needle.
Note that we probably still schedule some delayed actions that
are not needed.
Later we can optimize that further (related bug bgo #747985).
While some of these points could also have been implemented with
caching of libnl objects, that would have become hard to maintain.
https://bugzilla.gnome.org/show_bug.cgi?id=747981
NMPObject is a simple "object" implemenation around NMPlatformObject.
They are ref-counted and have a class-pointer. Several basic functions
like equality, hash, to-string are implemented.
NMPCache is can be used to store the NMPObject. Objects are indexed
via their primary id, but there is also multi-lookup via NMCacheId
and NMMultiIndex.
Part of the implementation is inside "nm-linux-platform.c",
because it depends on utility functions from there.
Cache the scope as part of the NMPlatformIP4Route and
no longer read it from libnl object when needed. Later
there will be no more libnl objects around, and we need
to scope when deleting an IPv4 route.
warning: function declaration isn’t a prototype [-Wstrict-prototypes]
In C function() and function(void) are two different prototypes (as opposed to
C++).
function() accepts an arbitrary number of arguments
function(void) accepts zero arguments
We already populate the netlink cache in constructed(). No need
to wait with udev devices until nm_platform_query_devices(). Just
do it right away.
Add a hack to keep 'lo' default-unmanaged. Now that we load
udev devices earlier, we end up clearing the default-unmanged
flag on 'lo', which has bad consequences.
We don't want error logging for nm_platform_link_add() which
tries to load the bonding module. Later we will run tests as non-root,
where modprobe will fail. Logging an error would break the tests.
We'd be able to do so for already existing devices, but not for devices that
are added afterwards, since gudev is hardwired not to listen for events from
kernel.
Ethernet, WiFi, and VLAN used the same implementation for initial address.
Ethernet and WiFi used the same implementation (and duplicated code) for
permanent MAC address, plus they both used ethtool in what should be
generic code, which is better done in the platform.
