If we add an absolute timeout to the back-end alarm-scheduler we must first
call 'handle' at the scheduler to update its internal time value.
Otherwise, it might happen that we add a timeout who's deadline is so big that
it normally belongs to the next time-counter period but the scheduler thinks
that it belongs to the current period as its time is older than the one used
to calculate the deadline.
Ref #2490
When we have two time values of an unsigned integer type and we create
the difference and want to know wether it is positive or negative within
the same value we loose at least one half of the value range for casting
to signed integers. This was the case in the alarm scheduler when
checking wether an alarm already triggered. Even worse, we casted from
'unsigned long' to 'signed int' which caused further loss on at least
x86_64. Thus, big timeouts like ~0UL falsely triggered directly.
Now, we use an extra boolean value to remember in which period of the
time counter we are and to which period of the time counter the deadline
of an alarm belongs. This boolean switches its value each time the time
counter wraps. This way, we can avoid any casting by checking wether the
current time is of the same period as the deadline of the alarm that we
inspect. If so, the alarm is pending if "current time >= alarm
deadline", otherwise it is pending if "current time < alarm deadline".
Ref #2490
If the PIT timer driver gets activated too slow (e.g. because of a bad priority
configuration), it might miss counter wraps and would than produce sudden time
jumps. The driver now detects this problem dynamically, warns about it and
adapts the affected values to avoid time jumps.
Ref #2400
The cache directory content is slightly different on each prepare-port
run and fortunately not used at build time. So, we just remove it at the
end of port preparation.
When using the elfweaver to generate boot images, python stores
precompiled modules in the source directory besides the .py files. This
changed the contrib source tree with binary files specific to the build
host. As a result the depot create tool picked up the changed source
tree and produced strange new hashes. Now, the tool sources are copied
to the build directory where python can do its optimizations and the
depot stays clean.
The NIC router always reports the link state "Up" (true) because
the effective link state depends on the targeted remote interface
and thus on the individual routing for each packet. Consequently,
also the signal handler for state changes gets ignored.
Ref #2490
IP stacks may treat a network interface as "down" when it states a MAC
address with the I/G bit (bit 40) set to "Group" (value 0) instead of
"Individual" (value 1). This was observed with a TinyCore 8 inside a
Virtualbox VM. Thus, the previously choosen 03:03:03:03:03:00 as base
for the MAC address allocator is bad. Now we use the 02:02:02:02:02:00
instead. This also ensures that the MAC addresses are not marked as
"Universal" but as "Local" (bit 41, value 1) which is correct in general
as the router allocates MAC addresses only for virtual networks.
Ref #2490
The timer driver should always be of the highest priority to avoid
problem with timers that have low max-counter values like the PIT
with only 53 ms.
Ref #2400
The NIC dump component didn't support forwarding of link states and link-state
signals until now. Furthermore, it now prints MAC address and link state
on session creation and on every link state change.
Ref #2490
Previously, the uplink session was created on component startup while the
creation of the downlink session is timed by the client component. This
created a time span in which packets from the uplink were dropped at the
nic_dump. Now the uplink session-request is done by the session component
of the downlink.
Ref #2490
