fixeria has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-bts/+/42524?usp=email )

Change subject: bts_shutdown_fsm: fix spurious RAMP_COMPL events in WAIT_TRX_CLOSED ......................................................................

bts_shutdown_fsm: fix spurious RAMP_COMPL events in WAIT_TRX_CLOSED

With multiple TRXes ramping down in lockstep, both their final ramp-timer callbacks fire back-to-back in the same event loop pass, setting p_total_cur_mdBm to the target value for both before any async hardware acknowledgement arrives. When the first SETPOWER ack returns and fires ramp_down_compl_cb() for TRX0, the remaining-TRX check in st_wait_ramp_down_compl() inspects p_total_cur_mdBm for TRX1 and finds it already at the target - concluding that all TRXes are done. The FSM then transitions to WAIT_TRX_CLOSED, and the second ack (for TRX1) fires ramp_down_compl_cb() into the wrong state, producing:

BTS_SHUTDOWN(...){WAIT_TRX_CLOSED}: Event BTS_SHUTDOWN_EV_TRX_RAMP_COMPL not permitted

The root cause is that p_total_cur_mdBm is a *requested* value set in the timer callback, not a confirmed one. The hardware confirmation arrives asynchronously via power_trx_change_compl() -> power_ramp_do_step(), which is also where compl_cb() is invoked.

Fix by adding a 'complete' flag to trx_power_params.ramp that is:

* cleared when _power_ramp_start() begins a new ramp, and * set just before compl_cb() is called in power_ramp_do_step()

The shutdown FSM remaining-TRX count then checks !ramp.complete instead of comparing p_total_cur_mdBm against the target, correctly reflecting which TRXes have actually received hardware confirmation of ramp completion.

Change-Id: Ia71393e871187d6b44b7f520eb421bab354aafd1 --- M include/osmo-bts/tx_power.h M src/common/bts_shutdown_fsm.c M src/common/tx_power.c 3 files changed, 6 insertions(+), 1 deletion(-)

git pull ssh://gerrit.osmocom.org:29418/osmo-bts refs/changes/24/42524/1

diff --git a/include/osmo-bts/tx_power.h b/include/osmo-bts/tx_power.h index 73134c8..52c02f5 100644 --- a/include/osmo-bts/tx_power.h +++ b/include/osmo-bts/tx_power.h @@ -1,6 +1,7 @@ #pragma once

#include <stdint.h> +#include <stdbool.h> #include <osmocom/core/timer.h>

/* our unit is 'milli dB" or "milli dBm", i.e. 1/1000 of a dB(m) */ @@ -59,6 +60,8 @@ struct osmo_timer_list step_timer; /* call-back called when target is reached */ ramp_compl_cb_t compl_cb; + /* set to true after compl_cb has been called (ramp target confirmed by hardware) */ + bool complete; } ramp; };

diff --git a/src/common/bts_shutdown_fsm.c b/src/common/bts_shutdown_fsm.c index 13a0e1d..a8c8f9d 100644 --- a/src/common/bts_shutdown_fsm.c +++ b/src/common/bts_shutdown_fsm.c @@ -110,7 +110,7 @@

llist_for_each_entry(trx, &bts->trx_list, list) { if (trx->mo.nm_state.operational == NM_OPSTATE_ENABLED && - trx->power_params.p_total_cur_mdBm > BTS_SHUTDOWN_POWER_RAMP_TGT) + !trx->power_params.ramp.complete) remaining++; }

diff --git a/src/common/tx_power.c b/src/common/tx_power.c index 1e026dd..575fe2f 100644 --- a/src/common/tx_power.c +++ b/src/common/tx_power.c @@ -210,6 +210,7 @@

/* we had finished in last loop iteration */ if (!first && tpp->ramp.attenuation_mdB == 0) { + tpp->ramp.complete = true; if (tpp->ramp.compl_cb) tpp->ramp.compl_cb(trx); return; @@ -261,6 +262,7 @@ /* set the new target */ tpp->p_total_tgt_mdBm = p_total_tgt_mdBm; tpp->ramp.compl_cb = ramp_compl_cb; + tpp->ramp.complete = false;

if (skip_ramping) { /* Jump straight to the target power */