tbf: Remove TimingAdvance storage

Currently the TA storage stores up to 30 TLLI->TA mappings, if more
entries are created the oldest one is dropped. In theory this can
lead to missing TA information if many MS are present.

This commit removes the TimingAdvance class completely, since the TA
value is now stored in the GprsMs objects.

Note that the GprsMs objects are currently not kept after the TBFs
have detached from them, so the TA values are now kept for a shorter
time than before.

Ticket: #1674
Sponsored-by: On-Waves ehf

6 files changed, 7 insertions, 195 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index b5456e00..35ba7a92 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -49,7 +49,6 @@ libgprs_la_SOURCES = \
 	bts.cpp \
 	poll_controller.cpp \
 	encoding.cpp \
-	ta.cpp \
 	sba.cpp \
 	decoding.cpp \
 	llc.cpp \
@@ -92,7 +91,6 @@ noinst_HEADERS = \
 	bts.h \
 	poll_controller.h \
 	encoding.h \
-	ta.h \
 	sba.h \
 	rlc.h \
 	decoding.h \
diff --git a/src/bts.cpp b/src/bts.cpp
index 010b8e88..7225a78c 100644
--- a/src/bts.cpp
+++ b/src/bts.cpp
@@ -945,7 +945,13 @@ void gprs_rlcmac_pdch::rcv_measurement_report(Packet_Measurement_Report_t *repor
 			"block, but there is no resource request "
 			"scheduled! TLLI=0x%08x\n", report->TLLI);
 	} else {
-		bts()->timing_advance()->remember(report->TLLI, sba->ta);
+		GprsMs *ms = bts()->ms_store().get_ms(report->TLLI);
+		if (!ms)
+			LOGP(DRLCMAC, LOGL_NOTICE, "MS send measurement "
+				"but TLLI 0x%08x is unknown\n", report->TLLI);
+		else
+			ms->set_ta(sba->ta);
+
 		bts()->sba()->free_sba(sba);
 	}
 	gprs_rlcmac_meas_rep(report);
diff --git a/src/bts.h b/src/bts.h
index 2e2d1467..28ecfc1c 100644
--- a/src/bts.h
+++ b/src/bts.h
@@ -30,7 +30,6 @@ extern "C" {
 
 #include "poll_controller.h"
 #include "sba.h"
-#include "ta.h"
 #include "tbf.h"
 #include "gprs_ms_storage.h"
 #endif
@@ -197,7 +196,6 @@ public:
 
 	struct gprs_rlcmac_bts *bts_data();
 	SBAController *sba();
-	TimingAdvance *timing_advance();
 
 	/** TODO: change the number to unsigned */
 	void set_current_frame_number(int frame_number);
@@ -254,7 +252,6 @@ private:
 	struct gprs_rlcmac_bts m_bts;
 	PollController m_pollController;
 	SBAController m_sba;
-	TimingAdvance m_ta;
 	struct rate_ctr_group *m_ratectrs;
 	gprs_rlcmac_tbf *tbf_by_tfi(uint8_t tfi, uint8_t trx, enum gprs_rlcmac_tbf_direction dir);
 
@@ -271,11 +268,6 @@ inline int BTS::current_frame_number() const
 	return m_cur_fn;
 }
 
-inline TimingAdvance *BTS::timing_advance()
-{
-	return &m_ta;
-}
-
 inline SBAController *BTS::sba()
 {
 	return &m_sba;
diff --git a/src/pcu_main.cpp b/src/pcu_main.cpp
index 08feb894..75e12634 100644
--- a/src/pcu_main.cpp
+++ b/src/pcu_main.cpp
@@ -244,8 +244,6 @@ int main(int argc, char *argv[])
 
 	pcu_l1if_close();
 
-	bts->bts->timing_advance()->flush();
-
 	talloc_report_full(tall_pcu_ctx, stderr);
 	talloc_free(tall_pcu_ctx);
 
diff --git a/src/ta.cpp b/src/ta.cpp
deleted file mode 100644
index 0bc1d660..00000000
--- a/src/ta.cpp
+++ /dev/null
@@ -1,142 +0,0 @@
-/*
- * ta.cpp timing advance handling
- * Copyright (C) 2012 Ivan Klyuchnikov
- * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu>
- * Copyright (C) 2013 by Holger Hans Peter Freyther
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
- */
-
-#include <ta.h>
-#include <gprs_rlcmac.h>
-
-extern "C" {
-	#include <osmocom/core/talloc.h>
-}
-
-#include <errno.h>
-
-extern void *tall_pcu_ctx;
-
-/*
- * timing advance memory
- */
-
-/* enable to debug timing advance memory */
-//#define DEBUG_TA
-
-struct gprs_rlcmac_ta {
-	struct llist_head	list;
-	uint32_t		tlli;
-	uint8_t			ta;
-};
-
-TimingAdvance::TimingAdvance()
-	: m_ta_len(0)
-{
-	INIT_LLIST_HEAD(&m_ta_list);
-}
-
-/* remember timing advance of a given TLLI */
-int TimingAdvance::remember(uint32_t tlli, uint8_t ta)
-{
-	struct gprs_rlcmac_ta *ta_entry;
-
-	/* check for existing entry */
-	llist_for_each_entry(ta_entry, &m_ta_list, list) {
-		if (ta_entry->tlli == tlli) {
-#ifdef DEBUG_TA
-			fprintf(stderr, "update %08x %d\n", tlli, ta);
-#endif
-			ta_entry->ta = ta;
-			/* relink to end of list */
-			llist_del(&ta_entry->list);
-			llist_add_tail(&ta_entry->list, &m_ta_list);
-			return 0;
-		}
-	}
-
-#ifdef DEBUG_TA
-	fprintf(stderr, "remember %08x %d\n", tlli, ta);
-#endif
-	/* if list is full, remove oldest entry */
-	if (m_ta_len == 30) {
-		ta_entry = llist_entry(m_ta_list.next,
-			struct gprs_rlcmac_ta, list);
-	        llist_del(&ta_entry->list);
-		talloc_free(ta_entry);
-		m_ta_len--;
-	}
-
-	/* create new TA entry */
-	ta_entry = talloc_zero(tall_pcu_ctx, struct gprs_rlcmac_ta);
-	if (!ta_entry)
-		return -ENOMEM;
-
-	ta_entry->tlli = tlli;
-	ta_entry->ta = ta;
-	llist_add_tail(&ta_entry->list, &m_ta_list);
-	m_ta_len++;
-
-	return 0;
-}
-
-int TimingAdvance::recall(uint32_t tlli)
-{
-	struct gprs_rlcmac_ta *ta_entry;
-	uint8_t ta;
-
-	llist_for_each_entry(ta_entry, &m_ta_list, list) {
-		if (ta_entry->tlli == tlli) {
-			ta = ta_entry->ta;
-#ifdef DEBUG_TA
-			fprintf(stderr, "recall %08x %d\n", tlli, ta);
-#endif
-			return ta;
-		}
-	}
-#ifdef DEBUG_TA
-	fprintf(stderr, "no entry for %08x\n", tlli);
-#endif
-
-	return -EINVAL;
-}
-
-int TimingAdvance::flush()
-{
-	struct gprs_rlcmac_ta *ta_entry;
-	int count = 0;
-
-	while (!llist_empty(&m_ta_list)) {
-		ta_entry = llist_entry(m_ta_list.next,
-			struct gprs_rlcmac_ta, list);
-#ifdef DEBUG_TA
-		fprintf(stderr, "flush entry %08x %d\n", ta_entry->tlli,
-			ta_entry->ta);
-#endif
-	        llist_del(&ta_entry->list);
-		talloc_free(ta_entry);
-		count++;
-	}
-	m_ta_len = 0;
-
-	return count;
-}
-
-int TimingAdvance::update(uint32_t, uint32_t new_tlli, uint8_t ta)
-{
-	/* for now just add the new entry and don't bother about the old one */
-	return remember(new_tlli, ta);
-}
diff --git a/src/ta.h b/src/ta.h
deleted file mode 100644
index 9b64280f..00000000
--- a/src/ta.h
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Copyright (C) 2012 Ivan Klyuchnikov
- * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu>
- * Copyright (C) 2013 by Holger Hans Peter Freyther
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
- */
-#pragma once
-
-extern "C" {
-#include <osmocom/core/linuxlist.h>
-}
-
-#include <stdint.h>
-
-class TimingAdvance {
-public:
-	TimingAdvance();
-
-	int update(uint32_t old_tlli, uint32_t new_tlli, uint8_t ta);
-	int remember(uint32_t tlli, uint8_t ta);
-	int recall(uint32_t tlli);
-	int flush();
-
-private:
-	size_t m_ta_len;
-	llist_head m_ta_list;	
-};