The checksums for forwarded/routed UDP, TCP and ICMP, used to be always
re-calculated from scratch in the NIC router although the router changes only
a few packet fields. This commit replaces the old approach whereever sensible
with an algorithm for incremental checksum updates suggested in RFC 1071.
The goal is to improve router performance.
Ref #4555
The checksums for forwarded/routed IPv4, used to be always re-calculated from
scratch in the NIC router although the router changes only a few packet fields.
This commit replaces the old approach whereever sensible with an algorithm for
incremental checksum updates suggested in RFC 1071. The goal is to improve
router performance.
Ref #4555
We used to use 'unsigned long' for the accumulating variable when calculating
internet checksums. However, 'signed long' is more in accordance with RFC 1071
and will allow us to share the same back end for folding, once we implement
incremental updating of internet checksums.
Ref #4555
Prevent public reflection of the only internally used 'init_sum' argument in
'uint16_t internet_checksum(...)' that, in addition, added a default value to
the function interface.
Ref #4555
When sending an ICMP ECHO reply, the router merely swaps SRC and DST of the
IPv4 header of the corresponding request and these changes cancel each other
out in checksum calculation. Therefore, with this commit, the router skips
updating the IPv4 checksum in this context.
Ref #4555
The router used to update IPv4 checksums when routing via an <ip> rule
despite the fact that it doesn't change any IPv4 header fields in this case.
Ref #4555
The NIC router used to update IPv4 and layer 4 checksums of a packet for each
interface it was sent to (say, all interfaces of the domain the packet was
routed to). However, there was and is no technical reason for not doing it
only once and then iterating over the interfaces with the already updated
packet. This is what this commit does in an intent to raise the router's
performance.
Ref #4555
The NIC router uses the timer for relatively coarse-grained timeouts.
It therefore suffices to update and store the current time when the NIC router
is signalled and use the cached time instead. This prevents frequent
syscalls or RPCs when acquiring the current time for every packet.
genodelabs/genode#4555
The link dissolve timeout is updated for every packet, which leads to
trigger_once() RPCs that only marginally change the scheduled timeout but
significantly slow down the packet throughput.
genodelabs/genode#4555
The wakeup call only emits a single signal as it assumed both are
handled by the same signal handler. However, the original implementation
did not reset the wakeup_needed variable properly.
genodelabs/genode#4555
When using signal batching, ack_avail and packet_avail should always
be emitted and preferred over ready_to_submit and ready_to_ack.
A signal receiver might decide to not register the ready_to_* signals when it
handles congestion by dropping packets. The Nic router is an example of
such a signal receiver.
genodelabs/genode#4555
Enables symetric-multi-processor support in the Linux kernel configuration
used as base for the driver ports for PC. This is done to be compliant with
common usage of x86 drivers today.
Moreover, this commit uses the original kernel source for softirq/tasklet
implementation to get rid of the insufficient shadow implementation
in the lx_emul sources.
Ref genodelabs/genode#4562
Prepare shadow implementations in spinlocks, pagetable defines,
and irq_stack assembler macros to be able to enable SMP on x86/PC.
Ref genodelabs/genode#4562
The test runs as lx_user task and uses several *delay and wait queue test
cases happened to be used in real ported linux drivers. The test shows
the time spent with several time sources, e.g. jiffies, rdtsc,
lx_time_counter_count etc.
Issue #4540
Use common implementation used by wifi and (not merged) audio driver.
Avoid usage of lib/delay.c since lpj and loop_for_jiffies are not calibrated
for the ported drivers as done on native Linux during boot and leads to wrong
delays for usb and intel_fb.
Issue #4540
Using the 'query_buffer_ppgtt()' function allows for retrieving the
virtual address of the buffer in the PPGTT.
This is for components that manage the GPU virtual addresses rather than
the client as is the case with the lima driver.
Issue #4559.
Adhere to include/linux/rcutiny.h behaviour, which sets the max timeout
for rcu_needs_cpu. Without the commit, in the most cases the timeout value
is zero (or random since the pointer is on stack uninitialized), which leads
to programming very short timeouts again and again, making the system never
idle.
Issue #4540
The box layout evenly distributes the child widgets according to the
number of children. This is not desired in the special case where a
child widget has a size of zero. The patch changes the layout algorithm
such that zero-sized widgets are not taken into account for distributing
residual space.
This patch replaces the former implicit "phonyness" of the rule by an
explicit .PHONY and installs a symlink from the target's build directory
to bin/ as is the usual practice for regular targets.
Related to issue #3972
The parent-provides model is destroyed if no <parent-provides> node is
found in the configuration, which resulted in
Warning: list model not empty at destruction time
and leaking memory for the allocated nodes. The commit now explicitly
empties the list model in the destructor of ~Parent_provides_model.
Note, the case is implicitly tested in pkg/test-init by step "denial of
forwarded session request" and <init_config version="empty">.
Thanks to Peter for reporting this issue.
Fixes#4547
