tbf: Use plain old data structure (PODS) for llist management
The PODS struct has a back pointer to access the actual object.
llist_pods_for_each_entry traverses the list of struct llist_pods and
makes the entry available (through the back pointer).
Ticket: SYS#389
Sponsored-by: On-Waves ehf
diff --git a/src/bts.cpp b/src/bts.cpp
index ff1a065..77c3f3e 100644
--- a/src/bts.cpp
+++ b/src/bts.cpp
@@ -138,6 +138,7 @@
{
uint8_t l, trx, ts, any_tbf = 0;
struct gprs_rlcmac_tbf *tbf;
+ struct llist_pods *lpods;
struct gprs_rlcmac_paging *pag;
uint8_t slot_mask[8];
int8_t first_ts; /* must be signed */
@@ -158,7 +159,7 @@
* Don't mark, if TBF uses a different slot that is already marked. */
memset(slot_mask, 0, sizeof(slot_mask));
for (l = 0; tbfs_lists[l]; l++) {
- llist_for_each_entry(tbf, tbfs_lists[l], list) {
+ llist_pods_for_each_entry(tbf, tbfs_lists[l], list, lpods) {
first_ts = -1;
for (ts = 0; ts < 8; ts++) {
if (tbf->pdch[ts]) {
@@ -232,15 +233,16 @@
gprs_rlcmac_tbf *BTS::tbf_by_tlli(uint32_t tlli, enum gprs_rlcmac_tbf_direction dir)
{
struct gprs_rlcmac_tbf *tbf;
+ struct llist_pods *lpods;
if (dir == GPRS_RLCMAC_UL_TBF) {
- llist_for_each_entry(tbf, &m_bts.ul_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &m_bts.ul_tbfs, list, lpods) {
OSMO_ASSERT(tbf->direction == dir);
if (tbf->state_is_not(GPRS_RLCMAC_RELEASING)
&& tbf->tlli() == tlli && tbf->is_tlli_valid())
return tbf;
}
} else {
- llist_for_each_entry(tbf, &m_bts.dl_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &m_bts.dl_tbfs, list, lpods) {
OSMO_ASSERT(tbf->direction == dir);
if (tbf->state_is_not(GPRS_RLCMAC_RELEASING)
&& tbf->tlli() == tlli)
@@ -253,10 +255,11 @@
gprs_rlcmac_dl_tbf *BTS::dl_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts)
{
struct gprs_rlcmac_dl_tbf *tbf;
+ struct llist_pods *lpods;
/* only one TBF can poll on specific TS/FN, because scheduler can only
* schedule one downlink control block (with polling) at a FN per TS */
- llist_for_each_entry(tbf, &m_bts.dl_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &m_bts.dl_tbfs, list, lpods) {
if (tbf->state_is_not(GPRS_RLCMAC_RELEASING)
&& tbf->poll_state == GPRS_RLCMAC_POLL_SCHED
&& tbf->poll_fn == fn && tbf->trx->trx_no == trx
@@ -270,10 +273,11 @@
gprs_rlcmac_ul_tbf *BTS::ul_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts)
{
struct gprs_rlcmac_ul_tbf *tbf;
+ struct llist_pods *lpods;
/* only one TBF can poll on specific TS/FN, because scheduler can only
* schedule one downlink control block (with polling) at a FN per TS */
- llist_for_each_entry(tbf, &m_bts.ul_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &m_bts.ul_tbfs, list, lpods) {
if (tbf->state_is_not(GPRS_RLCMAC_RELEASING)
&& tbf->poll_state == GPRS_RLCMAC_POLL_SCHED
&& tbf->poll_fn == fn && tbf->trx->trx_no == trx
@@ -1042,8 +1046,9 @@
enum gprs_rlcmac_tbf_direction dir)
{
gprs_rlcmac_tbf *tbf;
+ struct llist_pods *lpods;
- llist_for_each_entry(tbf, tbf_list, list) {
+ llist_pods_for_each_entry(tbf, tbf_list, list, lpods) {
OSMO_ASSERT(tbf->direction == dir);
if (tbf->tfi() != tfi)
continue;
diff --git a/src/gprs_rlcmac_sched.cpp b/src/gprs_rlcmac_sched.cpp
index 92e97ec..dab38d8 100644
--- a/src/gprs_rlcmac_sched.cpp
+++ b/src/gprs_rlcmac_sched.cpp
@@ -31,6 +31,7 @@
struct gprs_rlcmac_tbf **ul_ack_tbf)
{
struct gprs_rlcmac_tbf *tbf;
+ struct llist_pods *lpods;
uint32_t poll_fn;
/* check special TBF for events */
@@ -38,7 +39,7 @@
if ((block_nr % 3) == 2)
poll_fn ++;
poll_fn = poll_fn % 2715648;
- llist_for_each_entry(tbf, &bts->ul_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &bts->ul_tbfs, list, lpods) {
/* this trx, this ts */
if (tbf->trx->trx_no != trx || tbf->control_ts != ts)
continue;
@@ -54,7 +55,7 @@
*ul_ass_tbf = tbf;
#warning "Is this supposed to be fair? The last TBF for each wins? Maybe use llist_add_tail and skip once we have all states?"
}
- llist_for_each_entry(tbf, &bts->dl_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &bts->dl_tbfs, list, lpods) {
/* this trx, this ts */
if (tbf->trx->trx_no != trx || tbf->control_ts != ts)
continue;
diff --git a/src/poll_controller.cpp b/src/poll_controller.cpp
index 0f46472..dea75ed 100644
--- a/src/poll_controller.cpp
+++ b/src/poll_controller.cpp
@@ -33,10 +33,11 @@
struct gprs_rlcmac_bts *bts = m_bts.bts_data();
struct gprs_rlcmac_tbf *tbf;
struct gprs_rlcmac_sba *sba, *sba2;
+ struct llist_pods *lpods;
uint32_t elapsed;
/* check for poll timeout */
- llist_for_each_entry(tbf, &bts->ul_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &bts->ul_tbfs, list, lpods) {
if (tbf->poll_state == GPRS_RLCMAC_POLL_SCHED) {
elapsed = (frame_number + 2715648 - tbf->poll_fn)
% 2715648;
@@ -44,7 +45,7 @@
tbf->poll_timeout();
}
}
- llist_for_each_entry(tbf, &bts->dl_tbfs, list) {
+ llist_pods_for_each_entry(tbf, &bts->dl_tbfs, list, lpods) {
if (tbf->poll_state == GPRS_RLCMAC_POLL_SCHED) {
elapsed = (frame_number + 2715648 - tbf->poll_fn)
% 2715648;
diff --git a/src/tbf.cpp b/src/tbf.cpp
index 1201642..2257018 100644
--- a/src/tbf.cpp
+++ b/src/tbf.cpp
@@ -286,7 +286,7 @@
#warning "TODO: Could/Should generate bssgp_tx_llc_discarded"
tbf->m_llc.clear(tbf->bts);
tbf_unlink_pdch(tbf);
- llist_del(&tbf->list);
+ llist_del(&tbf->list.list);
if (tbf->direction == GPRS_RLCMAC_UL_TBF)
tbf->bts->tbf_ul_freed();
@@ -491,6 +491,9 @@
if (!tbf)
return -1;
+ /* Back pointer for PODS llist compatibility */
+ tbf->list.back = tbf;
+
tbf->m_created_ts = time(NULL);
tbf->bts = bts->bts;
tbf->m_tfi = tfi;
@@ -548,7 +551,7 @@
return NULL;
}
- llist_add(&tbf->list, &bts->ul_tbfs);
+ llist_add(&tbf->list.list, &bts->ul_tbfs);
tbf->bts->tbf_ul_created();
return tbf;
@@ -581,7 +584,7 @@
return NULL;
}
- llist_add(&tbf->list, &bts->dl_tbfs);
+ llist_add(&tbf->list.list, &bts->dl_tbfs);
tbf->bts->tbf_dl_created();
return tbf;
@@ -1805,11 +1808,11 @@
void gprs_rlcmac_tbf::rotate_in_list()
{
- llist_del(&list);
+ llist_del(&list.list);
if (direction == GPRS_RLCMAC_UL_TBF)
- llist_add(&list, &bts->bts_data()->ul_tbfs);
+ llist_add(&list.list, &bts->bts_data()->ul_tbfs);
else
- llist_add(&list, &bts->bts_data()->dl_tbfs);
+ llist_add(&list.list, &bts->bts_data()->dl_tbfs);
}
uint8_t gprs_rlcmac_tbf::tsc() const
@@ -1819,7 +1822,7 @@
void tbf_print_vty_info(struct vty *vty, llist_head *ltbf)
{
- gprs_rlcmac_tbf *tbf = llist_entry(ltbf, gprs_rlcmac_tbf, list);
+ gprs_rlcmac_tbf *tbf = llist_pods_entry(ltbf, gprs_rlcmac_tbf);
vty_out(vty, "TBF: TFI=%d TLLI=0x%08x (%s) DIR=%s IMSI=%s%s", tbf->tfi(),
tbf->tlli(), tbf->is_tlli_valid() ? "valid" : "invalid",
diff --git a/src/tbf.h b/src/tbf.h
index 4d20987..95355bd 100644
--- a/src/tbf.h
+++ b/src/tbf.h
@@ -84,6 +84,28 @@
#define GPRS_RLCMAC_FLAG_TO_DL_ASS 7
#define GPRS_RLCMAC_FLAG_TO_MASK 0xf0 /* timeout bits */
+struct llist_pods {
+ struct llist_head list;
+ void *back;
+};
+
+#define llist_pods_entry(ptr, type) \
+ ((type *)(container_of(ptr, struct llist_pods, list)->back))
+
+/**
+ * llist_pods_for_each_entry - like llist_for_each_entry, but uses
+ * struct llist_pods ->back to access the entry.
+ * This is necessary for non-PODS classes because container_of is
+ * not guaranteed to work anymore. */
+#define llist_pods_for_each_entry(pos, head, member, lpods) \
+ for (lpods = llist_entry((head)->next, typeof(struct llist_pods), list), \
+ pos = ((typeof(pos))lpods->back), \
+ prefetch(pos->member.list.next); \
+ &lpods->list != (head); \
+ lpods = llist_entry(lpods->list.next, typeof(struct llist_pods), list), \
+ pos = ((typeof(pos))lpods->back),\
+ prefetch(pos->member.list.next))
+
struct gprs_rlcmac_tbf {
static void free_all(struct gprs_rlcmac_trx *trx);
@@ -143,7 +165,7 @@
/* attempt to make things a bit more fair */
void rotate_in_list();
- struct llist_head list;
+ struct llist_pods list;
uint32_t state_flags;
enum gprs_rlcmac_tbf_direction direction;
struct gprs_rlcmac_trx *trx;