<p>neels <strong>submitted</strong> this change.</p><p><a href="https://gerrit.osmocom.org/c/osmo-bsc/+/24885">View Change</a></p><div style="white-space:pre-wrap">Approvals:
neels: Looks good to me, approved
Jenkins Builder: Verified
</div><pre style="font-family: monospace,monospace; white-space: pre-wrap;">RES IND: pick lchan with least interference<br><br>In lchan_select, do not return on the first available lchan, but iterate<br>through all available lchans. Among those that would match, pick the one<br>with the lowest interference level as indicated by earlier RES IND.<br><br>Lchans that have no interference ratings are picked last.<br><br>This feature is off by default, enable per BTS with<br><br> network<br> bts N<br> channel allocator avoid-interference 1<br><br>osmo-bsc still does the same ascending/descending lchan allocation as<br>before this patch with the default setting of:<br><br> channel allocator avoid-interference 0<br><br>Related: SYS#5313<br>Change-Id: I844494092193811dfd9fa4d52983cbaed0fc9248<br>---<br>M src/osmo-bsc/lchan_select.c<br>M tests/handover/test_resource_indication.ho_vty<br>2 files changed, 57 insertions(+), 29 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/src/osmo-bsc/lchan_select.c b/src/osmo-bsc/lchan_select.c</span><br><span>index efa2ff2..3618fb4 100644</span><br><span>--- a/src/osmo-bsc/lchan_select.c</span><br><span>+++ b/src/osmo-bsc/lchan_select.c</span><br><span>@@ -30,22 +30,36 @@</span><br><span> #include <osmocom/bsc/lchan_select.h></span><br><span> #include <osmocom/bsc/bts.h></span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+static struct gsm_lchan *pick_better_lchan(struct gsm_lchan *a, struct gsm_lchan *b)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!a)</span><br><span style="color: hsl(120, 100%, 40%);">+ return b;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!b)</span><br><span style="color: hsl(120, 100%, 40%);">+ return a;</span><br><span style="color: hsl(120, 100%, 40%);">+ /* comparing negative dBm values: smaller value means less interference. */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (b->interf_dbm < a->interf_dbm)</span><br><span style="color: hsl(120, 100%, 40%);">+ return b;</span><br><span style="color: hsl(120, 100%, 40%);">+ return a;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> static struct gsm_lchan *</span><br><span> _lc_find_trx(struct gsm_bts_trx *trx, enum gsm_phys_chan_config pchan,</span><br><span> enum gsm_phys_chan_config as_pchan, bool allow_pchan_switch, bool log)</span><br><span> {</span><br><span> struct gsm_lchan *lchan;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct gsm_lchan *found_lchan = NULL;</span><br><span> struct gsm_bts_trx_ts *ts;</span><br><span> int j, start, stop, dir;</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">-#define LOGPLCHANALLOC(fmt, args...) \</span><br><span style="color: hsl(120, 100%, 40%);">+#define LOGPLCHANALLOC(fmt, args...) do { \</span><br><span> if (log) \</span><br><span> LOGP(DRLL, LOGL_DEBUG, "looking for lchan %s%s%s%s: " fmt, \</span><br><span> gsm_pchan_name(pchan), \</span><br><span> pchan == as_pchan ? "" : " as ", \</span><br><span> pchan == as_pchan ? "" : gsm_pchan_name(as_pchan), \</span><br><span> ((pchan != as_pchan) && !allow_pchan_switch) ? " without pchan switch" : "", \</span><br><span style="color: hsl(0, 100%, 40%);">- ## args)</span><br><span style="color: hsl(120, 100%, 40%);">+ ## args); \</span><br><span style="color: hsl(120, 100%, 40%);">+ } while (0)</span><br><span> </span><br><span> if (!trx_is_usable(trx)) {</span><br><span> LOGPLCHANALLOC("%s trx not usable\n", gsm_trx_name(trx));</span><br><span>@@ -87,20 +101,43 @@</span><br><span> /* TS is (going to be) in desired pchan mode. Go ahead and check for an available lchan. */</span><br><span> lchans_as_pchan = pchan_subslots(as_pchan);</span><br><span> ts_for_n_lchans(lchan, ts, lchans_as_pchan) {</span><br><span style="color: hsl(0, 100%, 40%);">- if (lchan->fi->state == LCHAN_ST_UNUSED) {</span><br><span style="color: hsl(0, 100%, 40%);">- LOGPLCHANALLOC("%s ss=%d is available%s\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ struct gsm_lchan *was = found_lchan;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (lchan->fi->state != LCHAN_ST_UNUSED) {</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGPLCHANALLOC("%s ss=%d in type=%s,state=%s not suitable\n",</span><br><span> gsm_ts_and_pchan_name(ts), lchan->nr,</span><br><span style="color: hsl(0, 100%, 40%);">- ts->pchan_is != as_pchan ? " after dyn PCHAN change" : "");</span><br><span style="color: hsl(0, 100%, 40%);">- return lchan;</span><br><span style="color: hsl(120, 100%, 40%);">+ gsm_lchant_name(lchan->type),</span><br><span style="color: hsl(120, 100%, 40%);">+ osmo_fsm_inst_state_name(lchan->fi));</span><br><span style="color: hsl(120, 100%, 40%);">+ continue;</span><br><span> }</span><br><span style="color: hsl(0, 100%, 40%);">- LOGPLCHANALLOC("%s ss=%d in type=%s,state=%s not suitable\n",</span><br><span style="color: hsl(0, 100%, 40%);">- gsm_ts_and_pchan_name(ts), lchan->nr,</span><br><span style="color: hsl(0, 100%, 40%);">- gsm_lchant_name(lchan->type),</span><br><span style="color: hsl(0, 100%, 40%);">- osmo_fsm_inst_state_name(lchan->fi));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ found_lchan = pick_better_lchan(found_lchan, lchan);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (found_lchan != was)</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGPLCHANALLOC("%s ss=%d interf=%u=%ddBm is %s%s\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ gsm_ts_and_pchan_name(ts), lchan->nr,</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->interf_band, lchan->interf_dbm,</span><br><span style="color: hsl(120, 100%, 40%);">+ was == NULL ? "available" : "better",</span><br><span style="color: hsl(120, 100%, 40%);">+ ts->pchan_is != as_pchan ? ", after dyn PCHAN change" : "");</span><br><span style="color: hsl(120, 100%, 40%);">+ else</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGPLCHANALLOC("%s ss=%d interf=%u=%ddBm is also available but not better\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ gsm_ts_and_pchan_name(ts), lchan->nr,</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->interf_band, lchan->interf_dbm);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* When picking an lchan with least interference, continue to loop across all lchans. When</span><br><span style="color: hsl(120, 100%, 40%);">+ * ignoring interference levels, return the first match. */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (found_lchan && !trx->bts->chan_alloc_avoid_interf)</span><br><span style="color: hsl(120, 100%, 40%);">+ return found_lchan;</span><br><span> }</span><br><span> }</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- return NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (found_lchan)</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGPLCHANALLOC("%s ss=%d interf=%ddBm%s is the best pick\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ gsm_ts_and_pchan_name(found_lchan->ts), found_lchan->nr,</span><br><span style="color: hsl(120, 100%, 40%);">+ found_lchan->interf_dbm,</span><br><span style="color: hsl(120, 100%, 40%);">+ found_lchan->ts->pchan_is != as_pchan ? ", after dyn PCHAN change," : "");</span><br><span style="color: hsl(120, 100%, 40%);">+ else</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGPLCHANALLOC("Nothing found");</span><br><span style="color: hsl(120, 100%, 40%);">+ return found_lchan;</span><br><span> #undef LOGPLCHANALLOC</span><br><span> }</span><br><span> </span><br><span>diff --git a/tests/handover/test_resource_indication.ho_vty b/tests/handover/test_resource_indication.ho_vty</span><br><span>index 9dd9d38..724372e 100644</span><br><span>--- a/tests/handover/test_resource_indication.ho_vty</span><br><span>+++ b/tests/handover/test_resource_indication.ho_vty</span><br><span>@@ -12,8 +12,7 @@</span><br><span> </span><br><span> res-ind trx 0 0 levels - 1 2 3 4 3 2 -</span><br><span> create-ms bts 0 TCH/F AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 0 0 states * TCH/F - - - - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 0 0 states * - - - TCH/F - - *</span><br><span> </span><br><span> # The ordering may also be configured reversed, still the lowest dBm value should win</span><br><span> network</span><br><span>@@ -23,26 +22,22 @@</span><br><span> </span><br><span> res-ind trx 0 0 levels - 5 4 2 - 3 4 -</span><br><span> create-ms bts 0 TCH/F AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 0 0 states * TCH/F TCH/F - - - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 0 0 states * - - TCH/F TCH/F - - *</span><br><span> </span><br><span> # Favor lchans that have an indicated interference level</span><br><span> res-ind trx 0 0 levels - - - - - 4 3 -</span><br><span> create-ms bts 0 TCH/F AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 0 0 states * TCH/F TCH/F TCH/F - - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 0 0 states * - - TCH/F TCH/F - TCH/F *</span><br><span> </span><br><span> # For equal levels, pick the first</span><br><span> res-ind trx 0 0 levels - 2 2 - - 2 - -</span><br><span> create-ms bts 0 TCH/F AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 0 0 states * TCH/F TCH/F TCH/F TCH/F - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 0 0 states * TCH/F - TCH/F TCH/F - TCH/F *</span><br><span> </span><br><span> # Test clamping of indexes > 5</span><br><span> res-ind trx 0 0 levels - - 6 - - 4 - -</span><br><span> create-ms bts 0 TCH/F AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 0 0 states * TCH/F TCH/F TCH/F TCH/F TCH/F - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 0 0 states * TCH/F - TCH/F TCH/F TCH/F TCH/F *</span><br><span> </span><br><span> # Also test for TCH/H</span><br><span> create-bts trx-count 1 timeslots c+s4 TCH/H TCH/H TCH/H TCH/H TCH/H TCH/H PDCH</span><br><span>@@ -54,23 +49,19 @@</span><br><span> </span><br><span> res-ind trx 1 0 levels - 54 32 21 23 45 54 -</span><br><span> create-ms bts 1 TCH/H AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 1 0 states * TCH/H- - - - - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 1 0 states * - - TCH/-H - - - *</span><br><span> </span><br><span> # Favor lchans that have an indicated interference level</span><br><span> res-ind trx 1 0 levels - - - 4- 3- - - -</span><br><span> create-ms bts 1 TCH/H AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 1 0 states * TCH/HH - - - - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 1 0 states * - - TCH/-H TCH/H- - - *</span><br><span> </span><br><span> # For equal levels, pick the first</span><br><span> res-ind trx 1 0 levels - -2 22 2- -2 22 2- -</span><br><span> create-ms bts 1 TCH/H AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 1 0 states * TCH/HH TCH/H- - - - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 1 0 states * TCH/-H - TCH/-H TCH/H- - - *</span><br><span> </span><br><span> # Test clamping of indexes > 5</span><br><span> res-ind trx 1 0 levels - 7- 67 6- -7 54 6- -</span><br><span> create-ms bts 1 TCH/H AMR</span><br><span style="color: hsl(0, 100%, 40%);">-# FAIL: interference is ignored</span><br><span style="color: hsl(0, 100%, 40%);">-expect-ts-use trx 1 0 states * TCH/HH TCH/HH - - - - *</span><br><span style="color: hsl(120, 100%, 40%);">+expect-ts-use trx 1 0 states * TCH/-H - TCH/-H TCH/H- TCH/-H - *</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-bsc/+/24885">change 24885</a>. To unsubscribe, or for help writing mail filters, visit <a href="https://gerrit.osmocom.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.osmocom.org/c/osmo-bsc/+/24885"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: osmo-bsc </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: I844494092193811dfd9fa4d52983cbaed0fc9248 </div>
<div style="display:none"> Gerrit-Change-Number: 24885 </div>
<div style="display:none"> Gerrit-PatchSet: 5 </div>
<div style="display:none"> Gerrit-Owner: neels <nhofmeyr@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: Jenkins Builder </div>
<div style="display:none"> Gerrit-Reviewer: fixeria <vyanitskiy@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: laforge <laforge@osmocom.org> </div>
<div style="display:none"> Gerrit-Reviewer: neels <nhofmeyr@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: pespin <pespin@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: merged </div>