iwlwifi: mvm: reserve bandwidth for low-latency interface

If there is/are interface(s) in low-latency mode, reserve a
percentage (currently 64%) of the quota for that binding to
improve the quality of service for those interfaces. However,
if there's more than one binding that has low-latency, then
give up and don't reserve, we can't allocate more than 100%.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 49 insertions, 14 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/quota.c b/drivers/net/wireless/iwlwifi/mvm/quota.c
index ce5db6c4ef7e..0d2185b89d95 100644
--- a/drivers/net/wireless/iwlwifi/mvm/quota.c
+++ b/drivers/net/wireless/iwlwifi/mvm/quota.c
@@ -65,9 +65,14 @@
 #include "fw-api.h"
 #include "mvm.h"
 
+#define QUOTA_100       IWL_MVM_MAX_QUOTA
+#define QUOTA_LOWLAT_MIN ((QUOTA_100 * IWL_MVM_LOWLAT_QUOTA_MIN_PERCENT) / 100)
+
 struct iwl_mvm_quota_iterator_data {
         int n_interfaces[MAX_BINDINGS];
         int colors[MAX_BINDINGS];
+        int low_latency[MAX_BINDINGS];
+        int n_low_latency_bindings;
         struct ieee80211_vif *new_vif;
 };
 
@@ -107,22 +112,29 @@ static void iwl_mvm_quota_iterator(void *_data, u8 *mac,
         switch (vif->type) {
         case NL80211_IFTYPE_STATION:
                 if (vif->bss_conf.assoc)
-                        data->n_interfaces[id]++;
-                break;
+                        break;
+                return;
         case NL80211_IFTYPE_AP:
         case NL80211_IFTYPE_ADHOC:
                 if (mvmvif->ap_ibss_active)
-                        data->n_interfaces[id]++;
-                break;
+                        break;
+                return;
         case NL80211_IFTYPE_MONITOR:
                 if (mvmvif->monitor_active)
-                        data->n_interfaces[id]++;
-                break;
+                        break;
+                return;
         case NL80211_IFTYPE_P2P_DEVICE:
-                break;
+                return;
         default:
                 WARN_ON_ONCE(1);
-                break;
+                return;
+        }
+
+        data->n_interfaces[id]++;
+
+        if (iwl_mvm_vif_low_latency(mvmvif) && !data->low_latency[id]) {
+                data->n_low_latency_bindings++;
+                data->low_latency[id] = true;
         }
 }
 
@@ -162,7 +174,7 @@ static void iwl_mvm_adjust_quota_for_noa(struct iwl_mvm *mvm,
 int iwl_mvm_update_quotas(struct iwl_mvm *mvm, struct ieee80211_vif *newvif)
 {
         struct iwl_time_quota_cmd cmd = {};
-        int i, idx, ret, num_active_macs, quota, quota_rem;
+        int i, idx, ret, num_active_macs, quota, quota_rem, n_non_lowlat;
         struct iwl_mvm_quota_iterator_data data = {
                 .n_interfaces = {},
                 .colors = { -1, -1, -1, -1 },
@@ -197,11 +209,30 @@ int iwl_mvm_update_quotas(struct iwl_mvm *mvm, struct ieee80211_vif *newvif)
                 num_active_macs += data.n_interfaces[i];
         }
 
-        quota = 0;
-        quota_rem = 0;
-        if (num_active_macs) {
-                quota = IWL_MVM_MAX_QUOTA / num_active_macs;
-                quota_rem = IWL_MVM_MAX_QUOTA % num_active_macs;
+        n_non_lowlat = num_active_macs;
+
+        if (data.n_low_latency_bindings == 1) {
+                for (i = 0; i < MAX_BINDINGS; i++) {
+                        if (data.low_latency[i]) {
+                                n_non_lowlat -= data.n_interfaces[i];
+                                break;
+                        }
+                }
+                if (n_non_lowlat) {
+                        quota = (QUOTA_100 - QUOTA_LOWLAT_MIN) / n_non_lowlat;
+                        quota_rem = QUOTA_100 - n_non_lowlat * quota -
+                                    QUOTA_LOWLAT_MIN;
+                } else {
+                        quota = QUOTA_100;
+                        quota_rem = 0;
+                }
+        } else if (num_active_macs) {
+                quota = QUOTA_100 / num_active_macs;
+                quota_rem = QUOTA_100 % num_active_macs;
+        } else {
+                /* values don't really matter - won't be used */
+                quota = 0;
+                quota_rem = 0;
         }
 
         for (idx = 0, i = 0; i < MAX_BINDINGS; i++) {
@@ -214,6 +245,10 @@ int iwl_mvm_update_quotas(struct iwl_mvm *mvm, struct ieee80211_vif *newvif)
                 if (data.n_interfaces[i] <= 0) {
                         cmd.quotas[idx].quota = cpu_to_le32(0);
                         cmd.quotas[idx].max_duration = cpu_to_le32(0);
+                } else if (data.n_low_latency_bindings == 1 && n_non_lowlat &&
+                           data.low_latency[i]) {
+                        cmd.quotas[idx].quota = cpu_to_le32(QUOTA_LOWLAT_MIN);
+                        cmd.quotas[idx].max_duration = cpu_to_le32(0);
                 } else {
                         cmd.quotas[idx].quota =
                                 cpu_to_le32(quota * data.n_interfaces[i]);