* Added interfaces for the RLC to notify the PDCP of failure to transmit
SDU
* Limit discard timer to 1500ms, to avoid issues of lingering SDUs in the undeliverd_sdus_queue.
* Fix bug in early exit of notify_delivery and notify_failure
* fix compilation issue in rlc-pdcp notification
Co-authored-by: Francisco <francisco.paisana@softwareradiosystems.com>
* reuse vector capacity for pdcp sn notification
* use an extra lookup data structure to find PDCP SNs that an RLC SN contains
* fix rlc sn->pdcp sn lookup datastructure in rlc
* fix rlc failing test
Removing unecessary \n for logs and changed log of PDCP info queue
capacity to debug to avoid log spam.
Changed log level for unhandled S1AP messages from error to warning
in EPC to avoid failing tests because of error message.
Changed usage of allocate_unique_buffer to make_unique_buffer()
test. The race condition was being cause by write_sdu being called
simultanously to read_pdu, which could cause the read_pdu to try to get
the SDU info before it had been written by the write_sdu.
Changes in this commit include:
- Make sure PDCP sn in included in RLC AM stress test.
- Stop handling control PDU when TX is not enabled in RLC AM.
- Fixed issue with length of the PDCP SN in rlc_stress_test.
- Moved the place were sdu info erase was called to avoid double calls to erase
- Tentative fix for race condition in rlc_am_stress test.
- Added function to print information about undelivered_sdu_info_queue
for debugging.
PDCP PDUs. This includes:
- Modifying the byte_buffer_t to include PDCP SN meta-data. This way,
the RLC can keep track of the ack'ed bytes for a specific PDCP PDU.
- Added in the RLC an `undelivered_sdu_info queue`, to keep track of the
amount of ack'ed bytes and the total size of the PDCP PDU,
so the RLC can know when delivery is finished.
- Added an interface between the PDCP and the RLC so that the RLC can
notify the PDCP when it receives an ack from the status PDUs. The RLC
passes to the PDCP a vector of all the ack'ed pdus in a rx'ed status PDU.
- Added some tests to the notify functionality. This includes some tests
where the PDUs are acked imediatly, and one test where the PDU is
retx'ed.
this patch adds support for measuring the:
* SDU rx latency (Average time in ms from first RLC segment to full SDU)
* amount of buffered bytes (sum of payload of PDUs buffered in rx_window)
the implementation is using std::chrono
we've only incremented the retx when retransmitting a full PDU,
but not when only retransmitting segments.
This might lead to many more retx than allowed.
* rlc_am: add TC for pollRetx timer handling
* rlc_am: fix stopping of pollRetx timer
stopping the pollRetx timer when receiving a status PDU
without checking the acknowledged PDUs is wrong.
if an ACK for another PDU, for which the polling bit has been set,
is still pending, it won't be rescheduled until another
PDU is transmitted that again starts the pollRetx timer.
this fixes the issue with missing RLC AM segment retx in #1992,
and #2003
* mac_test: add extended TBSR unit test
unit test to MAC UL packing after sending a TBSR
this fixes the MAC issues described in issue #2002
* mux: fix updating of LCG buffer state after packing PDU
we've previously lowered the buffer state of the LCG according
to the bytes that have been scheduled, but not according to
those that have been actually included in the PDU.
* proc_bsr: fix LCG buffer state updating for TBSR
when sending a TBSR do not update the internal buffer
state of the BSR proc.
This caused issues because the buffer state for all LCG that
are not included in the TBSR are set to zero, although at least
one LCG does have data to transmit.
* rlc_am: include LCID when logging retx of SN
this makes sure that the reconstructed RLC AM header
has the poll bit set when any of its segments had it set.
this triggered a bug in RLC AM because the Status PDU
isn't transmitted for a RLC PDU that was segmented and
only the first segment had the P flag set.
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
This lock was removed in 1cbf7eac because it was considered unneeded.
However, as can be seen in issue #1503, we need to protect the access
to rx_window, for example.
Issue #1503 shows a stack trace where a PHY worker generates a status PDU.
While holding the mutex to access rx_window, the stack thread on the
other hand, happily accesses the rx_window member without acquiring
the lock. This commit protects all handle_*() functions in write_pdu().
This reverts commit 1cbf7eac04.
Francisco
Pedro Alvarez
Andre Puschmann
faluco