rlc: Add and use mod_sns(bsn) method
Currently there is only a mod_sns() method which is being used in
expression like bsn_expr & win.mod_sns(). This only works, because
it is known that mod_sns() is (sns() - 1) where sns() in turn is
always 2^n. This is error prone, hard to read, and relies on window
specifics that should be kept inside the respective module.
This commit adds a mod_sns(uint bsn) method to gprs_rlc_ul_window and
gprs_rlc_dl_window, that encapsulates and hides this optimized
computation.
Sponsored-by: On-Waves ehf
diff --git a/src/rlc.cpp b/src/rlc.cpp
index 227fa36..c733667 100644
--- a/src/rlc.cpp
+++ b/src/rlc.cpp
@@ -57,7 +57,7 @@
int gprs_rlc_dl_window::resend_needed()
{
- for (uint16_t bsn = v_a(); bsn != v_s(); bsn = (bsn + 1) & mod_sns()) {
+ for (uint16_t bsn = v_a(); bsn != v_s(); bsn = mod_sns(bsn + 1)) {
if (m_v_b.is_nacked(bsn) || m_v_b.is_resend(bsn))
return bsn;
}
@@ -69,7 +69,7 @@
{
int resend = 0;
- for (uint16_t bsn = v_a(); bsn != v_s(); bsn = (bsn + 1) & mod_sns()) {
+ for (uint16_t bsn = v_a(); bsn != v_s(); bsn = mod_sns(bsn + 1)) {
if (m_v_b.is_unacked(bsn)) {
/* mark to be re-send */
m_v_b.mark_resend(bsn);
@@ -85,7 +85,7 @@
uint16_t unacked = 0;
uint16_t bsn;
- for (bsn = v_a(); bsn != v_s(); bsn = (bsn + 1) & mod_sns()) {
+ for (bsn = v_a(); bsn != v_s(); bsn = mod_sns(bsn + 1)) {
if (!m_v_b.is_acked(bsn))
unacked += 1;
}
@@ -93,9 +93,9 @@
return unacked;
}
-static uint16_t bitnum_to_bsn(int bitnum, uint16_t ssn, uint16_t mod_sns)
+static uint16_t bitnum_to_bsn(int bitnum, uint16_t ssn)
{
- return (ssn - 1 - bitnum) & mod_sns;
+ return (ssn - 1 - bitnum);
}
void gprs_rlc_dl_window::update(BTS *bts, char *show_rbb, uint8_t ssn,
@@ -103,9 +103,9 @@
{
/* SSN - 1 is in range V(A)..V(S)-1 */
for (int bitpos = 0; bitpos < ws(); bitpos++) {
- uint16_t bsn = bitnum_to_bsn(bitpos, ssn, mod_sns());
+ uint16_t bsn = mod_sns(bitnum_to_bsn(bitpos, ssn));
- if (bsn == ((v_a() - 1) & mod_sns()))
+ if (bsn == mod_sns(v_a() - 1))
break;
if (show_rbb[ws() - 1 - bitpos] == 'R') {
@@ -128,7 +128,7 @@
uint16_t bsn;
int moved = 0;
- for (i = 0, bsn = v_a(); bsn != v_s(); i++, bsn = (bsn + 1) & mod_sns()) {
+ for (i = 0, bsn = v_a(); bsn != v_s(); i++, bsn = mod_sns(bsn + 1)) {
if (m_v_b.is_acked(bsn)) {
m_v_b.mark_invalid(bsn);
moved += 1;
@@ -144,7 +144,7 @@
int i;
uint16_t bsn;
- for (i = 0, bsn = v_a(); bsn != v_s(); i++, bsn = (bsn + 1) & mod_sns()) {
+ for (i = 0, bsn = v_a(); bsn != v_s(); i++, bsn = mod_sns(bsn + 1)) {
uint16_t index = bsn & mod_sns_half();
switch(m_v_b.get_state(index)) {
case GPRS_RLC_DL_BSN_INVALID:
@@ -188,7 +188,7 @@
void gprs_rlc_ul_window::raise_v_r(const uint16_t bsn)
{
uint16_t offset_v_r;
- offset_v_r = (bsn + 1 - v_r()) & mod_sns();
+ offset_v_r = mod_sns(bsn + 1 - v_r());
/* Positive offset, so raise. */
if (offset_v_r < (sns() >> 1)) {
while (offset_v_r--) {
@@ -212,7 +212,7 @@
if (!m_v_n.is_received(v_q()))
break;
LOGP(DRLCMACUL, LOGL_DEBUG, "- Taking block %d out, raising "
- "V(Q) to %d\n", v_q(), (v_q() + 1) & mod_sns());
+ "V(Q) to %d\n", v_q(), mod_sns(v_q() + 1));
raise_v_q(1);
count += 1;
}