[M] Change in osmocom-bb[master]: trxcon/l1sched: peoperly prioritize FACCH/H over TCH

fixeria has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmocom-bb/+/33709 ) Change subject: trxcon/l1sched: peoperly prioritize FACCH/H over TCH ...................................................................... trxcon/l1sched: peoperly prioritize FACCH/H over TCH Unlike FACCH/F, which steals one TCH frame, FACCH/H steals two TCH frames. This is what prim_dequeue_tchh() aims to implement, but the current implementation is not 100% correct. The problem is that we're attempting to dequeue and drop two TCH frames in one go, whenever we get a FACCH/H frame. Most likely, there will be no 2nd TCH frame in the Tx queue at that time, so it will never be dropped and will clog the queue. Let's replicate what osmo-bts-trx does: * dequeue and drop the 1st TCH frame when sending 1st/6 burst of FACCH, * dequeue and drop the 2nd TCH frame when sending 3rd/6 burst of FACCH. Change-Id: I513d6805ddf97783c002be285fb3ca7893e42377 Related: OS#4396, OS#1572 --- M src/host/trxcon/src/sched_lchan_tchh.c 1 file changed, 41 insertions(+), 27 deletions(-) git pull ssh://gerrit.osmocom.org:29418/osmocom-bb refs/changes/09/33709/1 diff --git a/src/host/trxcon/src/sched_lchan_tchh.c b/src/host/trxcon/src/sched_lchan_tchh.c index 6affbc5..67e2132 100644 --- a/src/host/trxcon/src/sched_lchan_tchh.c +++ b/src/host/trxcon/src/sched_lchan_tchh.c @@ -414,36 +414,23 @@ static struct msgb *prim_dequeue_tchh(struct l1sched_lchan_state *lchan, uint32_t fn) { - struct msgb *facch; - struct msgb *tch; - bool facch_now; + struct msgb *msg_facch; + struct msgb *msg_tch; - /* Can we initiate an UL FACCH/H frame transmission at this Fn? */ - facch_now = l1sched_tchh_facch_start(lchan->type, fn, true); - if (!facch_now) - goto no_facch; + /* dequeue a pair of TCH and FACCH frames */ + msg_tch = l1sched_lchan_prim_dequeue_tch(lchan, false); + if (l1sched_tchh_facch_start(lchan->type, fn, true)) + msg_facch = l1sched_lchan_prim_dequeue_tch(lchan, true); + else + msg_facch = NULL; - /* If there are no FACCH/H prims in the queue */ - facch = l1sched_lchan_prim_dequeue_tch(lchan, true); - if (!facch) /* Just dequeue a TCH/H prim */ - goto no_facch; - - /* FACCH/H prim replaces two TCH/F prims */ - tch = l1sched_lchan_prim_dequeue_tch(lchan, false); - if (tch) { - /* At least one TCH/H prim is dropped */ - msgb_free(tch); - - /* Attempt to find another */ - tch = l1sched_lchan_prim_dequeue_tch(lchan, false); - if (tch) /* Drop the second TCH/H prim */ - msgb_free(tch); + /* prioritize FACCH over TCH */ + if (msg_facch != NULL) { + msgb_free(msg_tch); /* drop 1st TCH/HS block */ + return msg_facch; } - return facch; - -no_facch: - return l1sched_lchan_prim_dequeue_tch(lchan, false); + return msg_tch; } int tx_tchh_fn(struct l1sched_lchan_state *lchan, @@ -478,8 +465,11 @@ *mask = *mask << 2; /* If FACCH/H blocks are still pending */ - if (lchan->ul_facch_blocks > 2) + if (lchan->ul_facch_blocks > 2) { + struct msgb *msg = l1sched_lchan_prim_dequeue_tch(lchan, false); + msgb_free(msg); /* drop 2nd TCH/HS block */ goto send_burst; + } lchan->prim = prim_dequeue_tchh(lchan, br->fn); if (lchan->prim == NULL) { -- To view, visit https://gerrit.osmocom.org/c/osmocom-bb/+/33709 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: osmocom-bb Gerrit-Branch: master Gerrit-Change-Id: I513d6805ddf97783c002be285fb3ca7893e42377 Gerrit-Change-Number: 33709 Gerrit-PatchSet: 1 Gerrit-Owner: fixeria &lt;vyanitskiy(a)sysmocom.de&gt; Gerrit-MessageType: newchange