From 832afa3f4b816797b6c9933187835a5c29cf5f1c Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Tue, 14 Jun 2016 13:12:00 +0200 Subject: dyn PDCH: set lchan->state after PDCH DEACT / before PDCH ACT Do the PDCH DE/ACT before we set the lchan->state to De-/Activation Requested. It makes more sense semantically to change PDCH mode while the lchan is still in NONE status. Thus slightly move some invocations: PDCH ACT: Free the lchan before PDCH activation. Hence remove the lchan_free() call from the rsl_rx_pdch_act_ack() code path; it used to do the PDCH activation first and call lchan_free() in the callback. PDCH DEACT: Set the (TCH) Activation Requested state only within rsl_chan_activate_lchan(), after the PDCH deact is complete. Channel allocator: don't pick channels that have a PDCH PENDING flag set, to avoid using channels that are still in PDCH switchover (despite their state being NONE). The lchan_may_change_pdch() sanity checks are becoming a lot simpler. Change-Id: I4206dd4808e21c3e59393ea7f5ab4f438afff066 --- openbsc/src/libbsc/abis_rsl.c | 28 +++++----------------------- openbsc/src/libbsc/chan_alloc.c | 7 +++++++ 2 files changed, 12 insertions(+), 23 deletions(-) (limited to 'openbsc') diff --git a/openbsc/src/libbsc/abis_rsl.c b/openbsc/src/libbsc/abis_rsl.c index 3aefd9c13..fc5686283 100644 --- a/openbsc/src/libbsc/abis_rsl.c +++ b/openbsc/src/libbsc/abis_rsl.c @@ -479,6 +479,8 @@ int rsl_chan_activate_lchan(struct gsm_lchan *lchan, uint8_t act_type, return rsl_ipacc_pdch_activate(lchan->ts, 0); } + rsl_lchan_set_state(lchan, LCHAN_S_ACT_REQ); + ta = lchan->rqd_ta; /* BS11 requires TA shifted by 2 bits */ @@ -756,12 +758,12 @@ static int rsl_rx_rf_chan_rel_ack(struct gsm_lchan *lchan) gsm_lchan_name(lchan), gsm_lchans_name(lchan->state)); + do_lchan_free(lchan); + /* Put PDCH channel back into PDCH mode first */ if (lchan->ts->pchan == GSM_PCHAN_TCH_F_PDCH) return rsl_ipacc_pdch_activate(lchan->ts, 1); - do_lchan_free(lchan); - return 0; } @@ -1204,7 +1206,6 @@ static int rsl_rx_hando_det(struct msgb *msg) static bool lchan_may_change_pdch(struct gsm_lchan *lchan, bool pdch_act) { struct gsm_bts_trx_ts *ts; - bool ok; OSMO_ASSERT(lchan); @@ -1222,22 +1223,7 @@ static bool lchan_may_change_pdch(struct gsm_lchan *lchan, bool pdch_act) return false; } - /* During BTS initialization, we expect to PDCH ACT in channel state == - * NONE. However, during dynamic channel switching, we will PDCH ACT - * while in state DEACTIVATION REQUESTED (we're deactivating TCH/F - * while activating PDCH); and we will PDCH DEACT while in state - * ACTIVATION REQUESTED (we're activating TCH/F while deactivating - * PDCH). */ - /* FIXME: rather switch PDCH while in state NONE, i.e. after - * deactivation of TCH/F and before activation of TCH/F? */ - if (pdch_act) - ok = (lchan->state == LCHAN_S_NONE - || lchan->state == LCHAN_S_REL_REQ); - else - ok = (lchan->state == LCHAN_S_NONE - || lchan->state == LCHAN_S_ACT_REQ); - - if (!ok) { + if (lchan->state != LCHAN_S_NONE) { LOGP(DRSL, LOGL_ERROR, "(bts %u, trx %u, ts %u, pchan %s)" " Rx PDCH %s ACK in unexpected state: %s\n", ts->trx->bts->nr, ts->trx->nr, ts->nr, @@ -1257,9 +1243,6 @@ static int rsl_rx_pdch_act_ack(struct msgb *msg) msg->lchan->ts->flags |= TS_F_PDCH_ACTIVE; msg->lchan->ts->flags &= ~TS_F_PDCH_ACT_PENDING; - /* We have activated PDCH, so now the channel is available again. */ - do_lchan_free(msg->lchan); - return 0; } @@ -1532,7 +1515,6 @@ static int rsl_rx_chan_rqd(struct msgb *msg) return -ENOMEM; } - rsl_lchan_set_state(lchan, LCHAN_S_ACT_REQ); memcpy(lchan->rqd_ref, rqd_ref, sizeof(*rqd_ref)); lchan->rqd_ta = rqd_ta; diff --git a/openbsc/src/libbsc/chan_alloc.c b/openbsc/src/libbsc/chan_alloc.c index 471578025..f4ed53087 100644 --- a/openbsc/src/libbsc/chan_alloc.c +++ b/openbsc/src/libbsc/chan_alloc.c @@ -43,6 +43,13 @@ static int ts_is_usable(struct gsm_bts_trx_ts *ts) return 0; } + /* If a dyn PDCH channel is busy changing, it is already taken or not + * yet available. */ + if (ts->pchan == GSM_PCHAN_TCH_F_PDCH) { + if (ts->flags & TS_F_PDCH_PENDING_MASK) + return 0; + } + return 1; } -- cgit v1.2.3