From c8d2166b86ed6c6071b2fed05257093e6ddd02e5 Mon Sep 17 00:00:00 2001 From: Pau Espin Pedrol Date: Tue, 28 Sep 2021 13:27:51 +0200 Subject: [PATCH] pdch: refactor rcv_control_ack() with a switch statement This clarifies the different paths and uniforms them. Makes code far easier to read and debug. New improved verification already found some misehavior in some tests. Change-Id: I7e4a88d6e004bbb7974595320ed73742162c7ad7 --- src/pdch.cpp | 85 ++++++++++++++++++++++++++++++++++------------------ 1 file changed, 56 insertions(+), 29 deletions(-) diff --git a/src/pdch.cpp b/src/pdch.cpp index 76acbcae..de77075a 100644 --- a/src/pdch.cpp +++ b/src/pdch.cpp @@ -344,37 +344,28 @@ void gprs_rlcmac_pdch::rcv_control_ack(Packet_Control_Acknowledgement_t *packet, fn, get_value_string(pdch_ulc_tbf_poll_reason_names, reason)); pdch_ulc_release_fn(ulc, fn); - /* check if this control ack belongs to packet uplink ack */ - ul_tbf = as_ul_tbf(tbf); - if (ul_tbf && reason == PDCH_ULC_POLL_UL_ACK && tbf_ul_ack_exp_ctrl_ack(ul_tbf, fn, ts_no)) { + switch (reason) { + case PDCH_ULC_POLL_UL_ACK: + ul_tbf = as_ul_tbf(tbf); + OSMO_ASSERT(ul_tbf); + if (!tbf_ul_ack_exp_ctrl_ack(ul_tbf, fn, ts_no)) { + LOGPTBF(tbf, LOGL_NOTICE, "FN=%d, TS=%d (curr FN %d): POLL_UL_ACK not expected!\n", + fn, ts_no, bts_current_frame_number(tbf->bts)); + return; + } osmo_fsm_inst_dispatch(ul_tbf->ul_ack_fsm.fi, TBF_UL_ACK_EV_RX_CTRL_ACK, NULL); /* We can free since we only set polling on final UL ACK/NACK */ LOGPTBF(tbf, LOGL_DEBUG, "[UPLINK] END\n"); tbf_free(tbf); return; - } - if (tbf->dl_ass_state_is(TBF_DL_ASS_WAIT_ACK)) { - LOGPTBF(tbf, LOGL_DEBUG, "[UPLINK] DOWNLINK ASSIGNED\n"); - /* reset N3105 */ - tbf->n_reset(N3105); - osmo_fsm_inst_dispatch(tbf->dl_ass_fsm.fi, TBF_DL_ASS_EV_RX_ASS_CTRL_ACK, NULL); - new_tbf = ms_dl_tbf(ms); - if (!new_tbf) { - LOGPDCH(this, DRLCMAC, LOGL_ERROR, "Got ACK, but DL " - "TBF is gone TLLI=0x%08x\n", tlli); + case PDCH_ULC_POLL_UL_ASS: + if (!tbf->ul_ass_state_is(TBF_UL_ASS_WAIT_ACK)) { + LOGPTBF(tbf, LOGL_NOTICE, "FN=%d, TS=%d (curr FN %d): POLL_UL_ASS not expected! state is %s\n", + fn, ts_no, bts_current_frame_number(tbf->bts), + osmo_fsm_inst_state_name(tbf_ul_ass_fi(tbf))); return; } - if (tbf->state_is(TBF_ST_WAIT_RELEASE) && - tbf->direction == new_tbf->direction) - tbf_free(tbf); - - osmo_fsm_inst_dispatch(new_tbf->state_fsm.fi, TBF_EV_ASSIGN_ACK_PACCH, NULL); - - tbf_assign_control_ts(new_tbf); - return; - } - if (tbf->ul_ass_state_is(TBF_UL_ASS_WAIT_ACK)) { LOGPTBF(tbf, LOGL_DEBUG, "[DOWNLINK] UPLINK ASSIGNED\n"); /* reset N3105 */ tbf->n_reset(N3105); @@ -398,10 +389,41 @@ void gprs_rlcmac_pdch::rcv_control_ack(Packet_Control_Acknowledgement_t *packet, * established */ if (ms_need_dl_tbf(new_tbf->ms())) new_tbf->establish_dl_tbf_on_pacch(); - return; - } - if (ms->nacc && nacc_fsm_exp_ctrl_ack(ms->nacc, fn, ts_no)) { + + case PDCH_ULC_POLL_DL_ASS: + if (!tbf->dl_ass_state_is(TBF_DL_ASS_WAIT_ACK)) { + LOGPTBF(tbf, LOGL_NOTICE, "FN=%d, TS=%d (curr FN %d): POLL_DL_ASS not expected! state is %s\n", + fn, ts_no, bts_current_frame_number(tbf->bts), + osmo_fsm_inst_state_name(tbf_dl_ass_fi(tbf))); + return; + } + LOGPTBF(tbf, LOGL_DEBUG, "[UPLINK] DOWNLINK ASSIGNED\n"); + /* reset N3105 */ + tbf->n_reset(N3105); + osmo_fsm_inst_dispatch(tbf->dl_ass_fsm.fi, TBF_DL_ASS_EV_RX_ASS_CTRL_ACK, NULL); + + new_tbf = ms_dl_tbf(ms); + if (!new_tbf) { + LOGPDCH(this, DRLCMAC, LOGL_ERROR, "Got ACK, but DL " + "TBF is gone TLLI=0x%08x\n", tlli); + return; + } + if (tbf->state_is(TBF_ST_WAIT_RELEASE) && + tbf->direction == new_tbf->direction) + tbf_free(tbf); + + osmo_fsm_inst_dispatch(new_tbf->state_fsm.fi, TBF_EV_ASSIGN_ACK_PACCH, NULL); + + tbf_assign_control_ts(new_tbf); + return; + + case PDCH_ULC_POLL_CELL_CHG_CONTINUE: + if (!ms->nacc || !nacc_fsm_exp_ctrl_ack(ms->nacc, fn, ts_no)) { + LOGPTBF(tbf, LOGL_NOTICE, "FN=%d, TS=%d (curr FN %d): POLL_CELL_CHG_CONTINUE not expected!\n", + fn, ts_no, bts_current_frame_number(tbf->bts)); + return; + } osmo_fsm_inst_dispatch(ms->nacc->fi, NACC_EV_RX_CELL_CHG_CONTINUE_ACK, NULL); /* Don't assume MS is no longer reachable (hence don't free) after this: TS 44.060 * "When the mobile station receives the PACKET CELL CHANGE ORDER @@ -412,10 +434,15 @@ void gprs_rlcmac_pdch::rcv_control_ack(Packet_Control_Acknowledgement_t *packet, * switch to a new cell." */ return; + + case PDCH_ULC_POLL_DL_ACK: + /* Handled in rcv_control_dl_ack_nack() upon receival of DL ACK/NACK as a response to our POLL. */ + return; + default: + LOGPDCH(this, DRLCMAC, LOGL_ERROR, "FN=%" PRIu32 " " + "Error: received PACKET CONTROL ACK at no request (reason=%s)\n", fn, + get_value_string(pdch_ulc_tbf_poll_reason_names, reason)); } - LOGPDCH(this, DRLCMAC, LOGL_ERROR, "FN=%" PRIu32 " " - "Error: received PACKET CONTROL ACK at no request (reason=%s)\n", fn, - get_value_string(pdch_ulc_tbf_poll_reason_names, reason)); } void gprs_rlcmac_pdch::rcv_control_dl_ack_nack(Packet_Downlink_Ack_Nack_t *ack_nack, uint32_t fn, struct pcu_l1_meas *meas)