alloc: Move the uplink ts selection/pre-assignment out of the code
Create a select_ul_slots which is very (95%) similar to the
select_dl_slots handling. This needs to be refactored and the
todo for multiple uplink slots should be handled too.
Add a warning about a potential failure on a busy PCU.
diff --git a/src/gprs_rlcmac_ts_alloc.cpp b/src/gprs_rlcmac_ts_alloc.cpp
index f65e673..171c204 100644
--- a/src/gprs_rlcmac_ts_alloc.cpp
+++ b/src/gprs_rlcmac_ts_alloc.cpp
@@ -376,6 +376,97 @@
}
/*
+ * Select a window of Tx slots if available.
+ * The maximum allowed slots depend on TX or the window of available
+ * slots.
+ */
+static int select_ul_slots(gprs_rlcmac_trx *trx,
+ const int ms_type, const int ms_max_txslots,
+ uint8_t tx_win_min, uint8_t tx_range,
+ int8_t *usf, int8_t *first_common_ts)
+{
+ int tsc = -1;
+ uint8_t tx_window = 0;
+ int i;
+ uint8_t ts_no;
+
+ for (ts_no = tx_win_min, i = 0; i < tx_range; ts_no = (ts_no + 1) & 7) {
+ gprs_rlcmac_pdch *pdch = &trx->pdch[ts_no];
+
+ /* check if enabled */
+ if (!pdch->is_enabled()) {
+ LOGP(DRLCMAC, LOGL_DEBUG, "- Skipping TS %d, "
+ "because not enabled\n", ts_no);
+ #warning "Why isn't it needed to increase the window?"
+ continue;
+ }
+ /* check if TSC changes */
+ if (tsc < 0)
+ tsc = pdch->tsc;
+ else if (tsc != pdch->tsc) {
+ LOGP(DRLCMAC, LOGL_ERROR, "Skipping TS %d of "
+ "TRX=%d, because it has different TSC "
+ "than lower TS of TRX. In order to "
+ "allow multislot, all slots must be "
+ "configured with the same TSC!\n",
+ ts_no, trx->trx_no);
+ /* increase window for Type 1 */
+ #warning "Why isn't it needed to check for tx_window"
+ if (ms_type == 1)
+ i++;
+ continue;
+ }
+ /* check for free usf */
+ usf[ts_no] = find_free_usf(pdch);
+ if (usf[ts_no] < 0) {
+ LOGP(DRLCMAC, LOGL_DEBUG, "- Skipping TS %d, "
+ "because no USF available\n", ts_no);
+ /* increase window for Type 1 */
+ if (ms_type == 1)
+ i++;
+ continue;
+ }
+
+ if (!tx_window)
+ *first_common_ts = ts_no;
+
+ tx_window |= (1 << ts_no);
+ LOGP(DRLCMAC, LOGL_DEBUG, "- Selected UL TS %d\n", ts_no);
+
+ if (1 && ms_type == 1) { /* FIXME: multislot UL assignment */
+ LOGP(DRLCMAC, LOGL_DEBUG, "- Done, because "
+ "1 slot assigned\n");
+ break;
+ }
+ if (++i == ms_max_txslots) {
+ LOGP(DRLCMAC, LOGL_DEBUG, "- Done, because "
+ "slots / window reached maximum "
+ "allowed Tx size\n");
+ break;
+ }
+ }
+
+ LOGP(DRLCMAC, LOGL_DEBUG, "- Selected TX window: "
+ "(TS=0)\"%c%c%c%c%c%c%c%c\"(TS=7)\n",
+ ((tx_window & 0x01)) ? 'U' : '.',
+ ((tx_window & 0x02)) ? 'U' : '.',
+ ((tx_window & 0x04)) ? 'U' : '.',
+ ((tx_window & 0x08)) ? 'U' : '.',
+ ((tx_window & 0x10)) ? 'U' : '.',
+ ((tx_window & 0x20)) ? 'U' : '.',
+ ((tx_window & 0x40)) ? 'U' : '.',
+ ((tx_window & 0x80)) ? 'U' : '.');
+
+ if (!tx_window) {
+ LOGP(DRLCMAC, LOGL_NOTICE, "No suitable uplink slots "
+ "available\n");
+ return -EBUSY;
+ }
+
+ return tx_window;
+}
+
+/*
* Assign the first common ts, which is used for control or
* single slot.
*/
@@ -412,11 +503,10 @@
uint8_t Tta, Ttb, Tra, Trb, Tt, Tr; /* Minimum Number of Slots */
uint8_t Type; /* Type of Mobile */
int rx_window;
- uint8_t tx_window = 0;
static const char *digit[10] = { "0","1","2","3","4","5","6","7","8","9" };
int8_t usf[8] = { -1, -1, -1, -1, -1, -1, -1, -1 }; /* must be signed */
int8_t first_common_ts = -1;
- uint8_t i, ts;
+ uint8_t ts;
uint8_t slotcount = 0;
@@ -486,89 +576,18 @@
tx_win_from_rx(ms_class->type, rx_win_min, rx_win_max, Tt, Tr,
&tx_win_min, &tx_win_max, &tx_range);
- /* select a window of Tx slots if available
- * The maximum allowed slots depend on TX or the window of available
- * slots.
- *
- * also assign the first common ts, which is used for control or single
- * slot. */
+ /* select UL slots but in both cases assign first_common_ts */
+ uint8_t tx_window = 0;
if (tbf->direction == GPRS_RLCMAC_UL_TBF) {
- int tsc = -1;
- for (ts = tx_win_min, i = 0; i < tx_range; ts = (ts + 1) & 7) {
- struct gprs_rlcmac_pdch *pdch;
- pdch = &tbf->trx->pdch[ts];
- /* check if enabled */
- if (!pdch->is_enabled()) {
- LOGP(DRLCMAC, LOGL_DEBUG, "- Skipping TS %d, "
- "because not enabled\n", ts);
- #warning "Why isn't it needed to increase the window?"
- continue;
- }
- /* check if TSC changes */
- if (tsc < 0)
- tsc = pdch->tsc;
- else if (tsc != pdch->tsc) {
- LOGP(DRLCMAC, LOGL_ERROR, "Skipping TS %d of "
- "TRX=%d, because it has different TSC "
- "than lower TS of TRX. In order to "
- "allow multislot, all slots must be "
- "configured with the same TSC!\n",
- ts, tbf->trx->trx_no);
- /* increase window for Type 1 */
- #warning "Why isn't it needed to check for tx_window"
- if (Type == 1)
- i++;
- continue;
- }
- /* check for free usf */
- usf[ts] = find_free_usf(pdch);
- if (usf[ts] < 0) {
- LOGP(DRLCMAC, LOGL_DEBUG, "- Skipping TS %d, "
- "because no USF available\n", ts);
- /* increase window for Type 1 */
- if (Type == 1)
- i++;
- continue;
- }
-
- if (!tx_window)
- first_common_ts = ts;
-
- tx_window |= (1 << ts);
- LOGP(DRLCMAC, LOGL_DEBUG, "- Selected UL TS %d\n", ts);
-
- if (1 && Type == 1) { /* FIXME: multislot UL assignment */
- LOGP(DRLCMAC, LOGL_DEBUG, "- Done, because "
- "1 slot assigned\n");
- break;
- }
- if (++i == Tx) {
- LOGP(DRLCMAC, LOGL_DEBUG, "- Done, because "
- "slots / window reached maximum "
- "allowed Tx size\n");
- break;
- }
- }
-
- LOGP(DRLCMAC, LOGL_DEBUG, "- Selected TX window: "
- "(TS=0)\"%c%c%c%c%c%c%c%c\"(TS=7)\n",
- ((tx_window & 0x01)) ? 'U' : '.',
- ((tx_window & 0x02)) ? 'U' : '.',
- ((tx_window & 0x04)) ? 'U' : '.',
- ((tx_window & 0x08)) ? 'U' : '.',
- ((tx_window & 0x10)) ? 'U' : '.',
- ((tx_window & 0x20)) ? 'U' : '.',
- ((tx_window & 0x40)) ? 'U' : '.',
- ((tx_window & 0x80)) ? 'U' : '.');
-
- if (!tx_window) {
- LOGP(DRLCMAC, LOGL_NOTICE, "No suitable uplink slots "
- "available\n");
- return -EBUSY;
- }
+ rc = select_ul_slots(tbf->trx, ms_class->type, ms_class->tx,
+ tx_win_min, tx_range, usf, &first_common_ts);
+ if (rc < 0)
+ return rc;
+ tx_window = rc;
} else {
first_common_ts = select_first_ts(tbf->trx, tx_win_min, tx_range);
}
+ #warning "first_common_ts might be different if there was no free USF for the new uplink assignment"
if (first_common_ts < 0) {
LOGP(DRLCMAC, LOGL_NOTICE, "No first common slots available\n");
@@ -600,12 +619,6 @@
}
}
} else {
- /* assign uplink */
- if (tx_window == 0) {
- LOGP(DRLCMAC, LOGL_NOTICE, "No uplink slots "
- "available\n");
- return -EINVAL;
- }
for (ts = 0; ts < 8; ts++) {
if ((tx_window & (1 << ts))) {
LOGP(DRLCMAC, LOGL_DEBUG, "- Assigning UL TS "