this patch refactors the SDU queuing and dropping policy of the RLC and PDCP layer.
the previous design had issues when packets have been generated at a higher
rate above the PDCP than they could be consumed below the RLC.
When the RLC SDU queues were full, we allowed two policies, one to block on the write
and the other to drop the SDU. Both options are not ideal because they either
lead to a blocking stack thread or to lost PDCP PDUs.
To avoid this, this patch makes the following changes:
* PDCP monitors RLC's SDU queue and drops packets on its north-bound SAP if queues are full
* a new method sdu_queue_is_full() has been added to the RLC interface for PDCP
* remove blocking write from pdcp and rlc write_sdu() interface
* all writes into queues need to be non-blocking
* if Tx queues are overflowing, SDUs are dropped above PDCP, not RLC
* log warning if RLC still needs to drop SDUs
* this case should be avoided with the monitoring mechanism
apply same change that we've done on the eNB also on the UE
to avoid the PHY processing TTIs faster than the stack.
Without that, we see lots of those in the logs:
...
08:39:17.580325 [STCK] [W] Detected slow task processing (sync_queue_len=7).
...
before entering RRC idle, after receiving a RRC connection release for example,
we need to wait until the RLC for SRB1 or SRB2 have been flushed, i.e.
the RLC has acknowledged the reception of the message.
Previously we have only waited for SRB1 but the message can also be received on SRB2
and in this case both bearers need to be checked.
The method is now streamlined to check both SRBs and is also used when
checking the msg transmission of an detach request.
The current TTI gap calculation assumes strict continuity
of radio time stamps, even when retuning, changing sample rate, etc.
This is certainly desireble but not necessaritly the case and may cause
issues when negative time gaps or too large gaps are detected and reported
to the stack.
this patch makes the assumption that valid TTI jumps are between 1ms
and 1s and that larger gaps are the result of screwed time-stamps
or too long radio operations.
extend GW-NAS interface to signal test mode activation.
The method is a noop in the normal GW but is implemented in
the TTCN3 DUT according to TS 36.509 for Mode B
This commit implements support for the CLOSE_UE_TEST_LOOP message.
Currently the mode is not saved and looping the data is not implemented.
Only the *_COMPLETE message is sent back as a response.
First of all, with this the NAS conformance tests pass with ciphering and
integrity turned on. Before only integrity was working.
Mainly the NAS was applying the integrity protection and/or ciphering
incorrectly because it wasn't taking the secuirty status of the PDUs
into account. Some where already correct, some not. The patch
streamlines the handling for all outgoing messages.
during deinit of the UE/eNB it could happen that the log_ptr
was already set to null but the stack thread was still accessing
it through log_h->info()
i've moved the old macro into a new header and used as as much
as possible. there are still places in the code where similar
macros are used but we would need to change the variable name
to replace them
this is to better differentiate from "send_attach_request" that
only packs and send the actual attach request message. The
entire attach procedure may include PLMN search, etc.
* Use task id to track old background tasks in RA procedure
* Improve robustness against RF overflow in PHY
* Increase SNR out-of-sync threshold
* Do not change frequency if it's the same
* Increase sync priority
* Increase time to start receiving to reduce input buffer occupation
* Use scoped lock in sf_worker
- move handling to NAS
- use switch off to enable airplane mode (don't wait for EPC response)
- add tiny FSM to control airplane mode activation/deactivation
- only start on/off counter after state has been entered