iwlwifi: mvm: rs: refactor rate scale action decision
Extract the scale action decision to a different function
in preparation of modifying it. While at it also convert
the scale action values from hardcoded values to a clear enum.
Signed-off-by: Eyal Shapira <eyal@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/mvm/rs.c b/drivers/net/wireless/iwlwifi/mvm/rs.c
index 6d0bd45..62b29d7 100644
--- a/drivers/net/wireless/iwlwifi/mvm/rs.c
+++ b/drivers/net/wireless/iwlwifi/mvm/rs.c
@@ -130,6 +130,12 @@
IWL_DECLARE_MCS_RATE(9), /* MCS 9 */
};
+enum rs_action {
+ RS_ACTION_STAY = 0,
+ RS_ACTION_DOWNSCALE = -1,
+ RS_ACTION_UPSCALE = 1,
+};
+
enum rs_column_mode {
RS_INVALID = 0,
RS_LEGACY,
@@ -1616,6 +1622,97 @@
return -1;
}
+static enum rs_action rs_get_rate_action(struct iwl_mvm *mvm,
+ struct iwl_scale_tbl_info *tbl,
+ s32 sr, int low, int high,
+ int current_tpt,
+ int low_tpt, int high_tpt)
+{
+ enum rs_action action = RS_ACTION_STAY;
+
+ /* Too many failures, decrease rate */
+ if ((sr <= RS_SR_FORCE_DECREASE) || (current_tpt == 0)) {
+ IWL_DEBUG_RATE(mvm,
+ "decrease rate because of low SR\n");
+ action = RS_ACTION_DOWNSCALE;
+ /* No throughput measured yet for adjacent rates; try increase. */
+ } else if ((low_tpt == IWL_INVALID_VALUE) &&
+ (high_tpt == IWL_INVALID_VALUE)) {
+ if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH) {
+ IWL_DEBUG_RATE(mvm,
+ "Good SR and no high rate measurement. "
+ "Increase rate\n");
+ action = RS_ACTION_UPSCALE;
+ } else if (low != IWL_RATE_INVALID) {
+ IWL_DEBUG_RATE(mvm,
+ "Remain in current rate\n");
+ action = RS_ACTION_STAY;
+ }
+ }
+
+ /* Both adjacent throughputs are measured, but neither one has better
+ * throughput; we're using the best rate, don't change it!
+ */
+ else if ((low_tpt != IWL_INVALID_VALUE) &&
+ (high_tpt != IWL_INVALID_VALUE) &&
+ (low_tpt < current_tpt) &&
+ (high_tpt < current_tpt)) {
+ IWL_DEBUG_RATE(mvm,
+ "Both high and low are worse. "
+ "Maintain rate\n");
+ action = RS_ACTION_STAY;
+ }
+
+ /* At least one adjacent rate's throughput is measured,
+ * and may have better performance.
+ */
+ else {
+ /* Higher adjacent rate's throughput is measured */
+ if (high_tpt != IWL_INVALID_VALUE) {
+ /* Higher rate has better throughput */
+ if (high_tpt > current_tpt &&
+ sr >= IWL_RATE_INCREASE_TH) {
+ IWL_DEBUG_RATE(mvm,
+ "Higher rate is better and good "
+ "SR. Increate rate\n");
+ action = RS_ACTION_UPSCALE;
+ } else {
+ IWL_DEBUG_RATE(mvm,
+ "Higher rate isn't better OR "
+ "no good SR. Maintain rate\n");
+ action = RS_ACTION_STAY;
+ }
+
+ /* Lower adjacent rate's throughput is measured */
+ } else if (low_tpt != IWL_INVALID_VALUE) {
+ /* Lower rate has better throughput */
+ if (low_tpt > current_tpt) {
+ IWL_DEBUG_RATE(mvm,
+ "Lower rate is better. "
+ "Decrease rate\n");
+ action = RS_ACTION_DOWNSCALE;
+ } else if (sr >= IWL_RATE_INCREASE_TH) {
+ IWL_DEBUG_RATE(mvm,
+ "Lower rate isn't better and "
+ "good SR. Increase rate\n");
+ action = RS_ACTION_UPSCALE;
+ }
+ }
+ }
+
+ /* Sanity check; asked for decrease, but success rate or throughput
+ * has been good at old rate. Don't change it.
+ */
+ if ((action == RS_ACTION_DOWNSCALE) && (low != IWL_RATE_INVALID) &&
+ ((sr > IWL_RATE_HIGH_TH) ||
+ (current_tpt > (100 * tbl->expected_tpt[low])))) {
+ IWL_DEBUG_RATE(mvm,
+ "Sanity check failed. Maintain rate\n");
+ action = RS_ACTION_STAY;
+ }
+
+ return action;
+}
/*
* Do rate scaling and search for new modulation mode.
@@ -1636,7 +1733,7 @@
int low_tpt = IWL_INVALID_VALUE;
int high_tpt = IWL_INVALID_VALUE;
u32 fail_count;
- s8 scale_action = 0;
+ enum rs_action scale_action = RS_ACTION_STAY;
u16 rate_mask;
u8 update_lq = 0;
struct iwl_scale_tbl_info *tbl, *tbl1;
@@ -1830,85 +1927,8 @@
rs_pretty_lq_type(rate->type), index, current_tpt, sr,
low, high, low_tpt, high_tpt);
- scale_action = 0;
-
- /* Too many failures, decrease rate */
- if ((sr <= RS_SR_FORCE_DECREASE) || (current_tpt == 0)) {
- IWL_DEBUG_RATE(mvm,
- "decrease rate because of low SR\n");
- scale_action = -1;
- /* No throughput measured yet for adjacent rates; try increase. */
- } else if ((low_tpt == IWL_INVALID_VALUE) &&
- (high_tpt == IWL_INVALID_VALUE)) {
- if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH) {
- IWL_DEBUG_RATE(mvm,
- "Good SR and no high rate measurement. "
- "Increase rate\n");
- scale_action = 1;
- } else if (low != IWL_RATE_INVALID) {
- IWL_DEBUG_RATE(mvm,
- "Remain in current rate\n");
- scale_action = 0;
- }
- }
-
- /* Both adjacent throughputs are measured, but neither one has better
- * throughput; we're using the best rate, don't change it! */
- else if ((low_tpt != IWL_INVALID_VALUE) &&
- (high_tpt != IWL_INVALID_VALUE) &&
- (low_tpt < current_tpt) &&
- (high_tpt < current_tpt)) {
- IWL_DEBUG_RATE(mvm,
- "Both high and low are worse. "
- "Maintain rate\n");
- scale_action = 0;
- }
-
- /* At least one adjacent rate's throughput is measured,
- * and may have better performance. */
- else {
- /* Higher adjacent rate's throughput is measured */
- if (high_tpt != IWL_INVALID_VALUE) {
- /* Higher rate has better throughput */
- if (high_tpt > current_tpt &&
- sr >= IWL_RATE_INCREASE_TH) {
- IWL_DEBUG_RATE(mvm,
- "Higher rate is better and good "
- "SR. Increate rate\n");
- scale_action = 1;
- } else {
- IWL_DEBUG_RATE(mvm,
- "Higher rate isn't better OR "
- "no good SR. Maintain rate\n");
- scale_action = 0;
- }
-
- /* Lower adjacent rate's throughput is measured */
- } else if (low_tpt != IWL_INVALID_VALUE) {
- /* Lower rate has better throughput */
- if (low_tpt > current_tpt) {
- IWL_DEBUG_RATE(mvm,
- "Lower rate is better. "
- "Decrease rate\n");
- scale_action = -1;
- } else if (sr >= IWL_RATE_INCREASE_TH) {
- IWL_DEBUG_RATE(mvm,
- "Lower rate isn't better and "
- "good SR. Increase rate\n");
- scale_action = 1;
- }
- }
- }
-
- /* Sanity check; asked for decrease, but success rate or throughput
- * has been good at old rate. Don't change it. */
- if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
- ((sr > IWL_RATE_HIGH_TH) ||
- (current_tpt > (100 * tbl->expected_tpt[low])))) {
- IWL_DEBUG_RATE(mvm,
- "Sanity check failed. Maintain rate\n");
- scale_action = 0;
- }
+ scale_action = rs_get_rate_action(mvm, tbl, sr, low, high,
+ current_tpt, low_tpt, high_tpt);
/* Force a search in case BT doesn't like us being in MIMO */
if (is_mimo(rate) &&
@@ -1920,7 +1940,7 @@
}
switch (scale_action) {
- case -1:
+ case RS_ACTION_DOWNSCALE:
/* Decrease starting rate, update uCode's rate table */
if (low != IWL_RATE_INVALID) {
update_lq = 1;
@@ -1931,7 +1951,7 @@
}
break;
- case 1:
+ case RS_ACTION_UPSCALE:
/* Increase starting rate, update uCode's rate table */
if (high != IWL_RATE_INVALID) {
update_lq = 1;
@@ -1942,7 +1962,7 @@
}
break;
- case 0:
+ case RS_ACTION_STAY:
/* No change */
default:
break;