The RRC PDU Session struct is converted from a fixed-size array
to a dynamically sized seq_arr. This improves flexibility and
simplifies session management by eliminating arbitrary size limits
and enabling dynamic addition/removal of PDU sessions.
Helper functions and loops have been adapted to use the seq_arr API.
This change is a step toward more robust and maintainable handling
of PDU sessions in the gNB RRC layer.
The "status" state machine remains untouched in this commit and
is refactored in a later commit.
Also:
* add macro to push to seq_arr and return the new element
* move initialization of xid (RRC PDU Session struct) to
find_pduSession (temporary, will be finalized in a later
commit) since with the new seq_arr design the initialization
is no longer possible in the UE context generation (also
does not belong to it, initialize when adding a new PDU Session)
Remove sched_ctrl->sched_ulsch, and call the post-processing function
post_process_ulsch() in the places where sched_ctrl->sched_ulsch has
been assigned. This will have two effects:
- it is not necessary to have the final loop over all UEs, which might
be costly especially towards many UEs.
- till now, there is only a single sched_ulsch; however, a later commit
will allow to schedule multiple PUSCH transmissions from a single (DL)
slot. This would require to make sched_ctrl->sched_ulsch, and
also iterate through all sched_ulsch. In this new scheme, we can
simply call post_process_ulsch() multiple times, which is simpler (and
therefore, implicitly handleded as of this commit).
Motivation:
Clarify the role of GTP tunnel endpoint IDs in PDU session handling. Previously,
the struct members (gNB_teid_N3, UPF_teid_N3, etc.) were confusingly named and
duplicated with separate transport-layer address fields.
This refactoring replaces these with explicit n3_incoming and n3_outgoing members using
gtpu_tunnel_t. This aligns with GTP conventions: "incoming TEID" refers to the
TEID received from the remote peer (UPF on N3), while "outgoing TEID" is the
TEID sent by the local entity (NG-RAN on N3) to the remote peer.
Benefits:
* Improves readability and clarity of the code
* Reduces redundant struct members, i.e. remove UPF_teid_N3, UPF_addr_N3
* Aligns naming with 3GPP conventions for transport layer tunnels
Changes:
* Replace gtp_addr_N3, gNB_teid_N3, gtp_teid, upf_addr with n3_incoming and n3_outgoing
* Update all related code to use the new struct members
* Aligns naming with 3GPP conventions for transport layer tunnels
* Remove the ulsch_slot_bitmap and dlsch_slot_bitmap from nrmac
* Adopt the new is_dl_slot/is_ul_slot functions in the stack
to replace is_xlsch_in_slot: these functions are getting
the DL and UL slots as they are set in the TDD configuration
stored in tdd_slot_bitmap (frame_structure_t)
* Keep is_xlsch_in_slot in openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_phytest.c:
this is necessary because the phy-test pre-processors are using the bitmaps
dlsch_slot_bitmap and ulsch_slot_bitmap to check which DL/UL slots to use
for transmission among those set in the TDD configuration
Co-authored-by: Guido Casati <guido.casati@firecell.io>
The asserts might be used to intentionally stop the running process.
Further, it might be an annoyance if it happen unintentionally. Just
print an error message instead, and return to FlexRIC that nothing is to
be sent.
- e2_ran_func library divided into e2_ran_func_cuup (CU-UP only) and e2_ran_func_du_cucp_cuup (DU, CU, CU-CP and gNB-mono)
- GTP SM is not yet implemented in CU-UP -> CU-UP doesn't store PDU session information
- PDCP SM support for gNB-mono, CU and CU-UP
- KPM SM support for all node types (DU, CU, CU-UP, CU-CP and gNB-mono)