wifi: iwlwifi: mld: consider channel load when grading a link
In link selection, we assign a grade to each link. This grade should be
multiplied by the channel load factor (the percentage of the unutilized
channel).
This factor is calculated by subtracting the channel_load_by_us (as
received from the FW statistics) from the overall channel load, as
published by the AP in the channel utilization element.
If the channel utilization element is not available, we use default
values.
type=feature
ticket=jira:WIFI-371607
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Change-Id: I180bdcd70509b7831f051f94291d4c49c6652b5c
Reviewed-on: https://gerritwcs.ir.intel.com/c/iwlwifi-stack-dev/+/169281
tested: iil_jenkins iil_jenkins <EC.GER.UNIX.IIL.JENKINS@INTEL.COM>
x-iwlwifi-stack-dev: 2319e6a662dea7a572e5fca79c80449b452e2483
diff --git a/drivers/net/wireless/intel/iwlwifi/mld/link.c b/drivers/net/wireless/intel/iwlwifi/mld/link.c
index 063ba9e..1d3447c 100644
--- a/drivers/net/wireless/intel/iwlwifi/mld/link.c
+++ b/drivers/net/wireless/intel/iwlwifi/mld/link.c
@@ -677,9 +677,16 @@
#define MAX_GRADE (rssi_to_grade_map[ARRAY_SIZE(rssi_to_grade_map) - 1].grade)
-#define DEFAULT_CHAN_LOAD_LB 30
-#define DEFAULT_CHAN_LOAD_HB 15
-#define DEFAULT_CHAN_LOAD_UHB 0
+#define DEFAULT_CHAN_LOAD_2GHZ 30
+#define DEFAULT_CHAN_LOAD_5GHZ 15
+#define DEFAULT_CHAN_LOAD_6GHZ 0
+
+/* Factors calculation is done with fixed-point with a scaling factor of 1/256 */
+#define SCALE_FACTOR 256
+#define MAX_CHAN_LOAD 256
+
+/* Convert a percentage from [0,100] to [0,255] */
+#define NORMALIZE_PERCENT_TO_255(percentage) ((percentage) * SCALE_FACTOR / 100)
static unsigned int
iwl_mld_get_n_subchannels(const struct ieee80211_bss_conf *link_conf)
@@ -703,6 +710,122 @@
return n_subchannels;
}
+static int
+iwl_mld_get_chan_load_from_element(struct iwl_mld *mld,
+ struct ieee80211_bss_conf *link_conf)
+{
+ struct ieee80211_vif *vif = link_conf->vif;
+ const struct cfg80211_bss_ies *ies;
+ const struct element *bss_load_elem = NULL;
+ const struct ieee80211_bss_load_elem *bss_load;
+
+ if (ieee80211_vif_link_active(vif, link_conf->link_id))
+ ies = wiphy_dereference(mld->wiphy, link_conf->bss->beacon_ies);
+ else
+ ies = wiphy_dereference(mld->wiphy, link_conf->bss->ies);
+
+ if (ies)
+ bss_load_elem = cfg80211_find_elem(WLAN_EID_QBSS_LOAD,
+ ies->data, ies->len);
+
+ if (!bss_load_elem ||
+ bss_load_elem->datalen != sizeof(*bss_load))
+ return -EINVAL;
+
+ bss_load = (const void *)bss_load_elem->data;
+
+ return bss_load->channel_util;
+}
+
+static unsigned int
+iwl_mld_get_chan_load_by_us(struct iwl_mld *mld,
+ struct ieee80211_bss_conf *link_conf)
+{
+ struct iwl_mld_link *mld_link = iwl_mld_link_from_mac80211(link_conf);
+ struct ieee80211_chanctx_conf *chan_ctx;
+ struct iwl_mld_phy *phy;
+
+ if (!mld_link || !mld_link->active)
+ return 0;
+
+ if (WARN_ONCE(!rcu_access_pointer(mld_link->chan_ctx),
+ "Active link (%u) without channel ctxt assigned!\n",
+ link_conf->link_id))
+ return 0;
+
+ chan_ctx = wiphy_dereference(mld->wiphy, mld_link->chan_ctx);
+ phy = iwl_mld_phy_from_mac80211(chan_ctx);
+
+ return phy->channel_load_by_us;
+}
+
+/* Returns error if the channel utilization element is invalid/unavailable */
+static int iwl_mld_get_chan_load_by_others(struct iwl_mld *mld,
+ struct ieee80211_bss_conf *link_conf)
+{
+ int chan_load;
+ unsigned int chan_load_by_us;
+
+ /* get overall load */
+ chan_load = iwl_mld_get_chan_load_from_element(mld, link_conf);
+ if (chan_load < 0)
+ return chan_load;
+
+ chan_load_by_us = iwl_mld_get_chan_load_by_us(mld, link_conf);
+
+ /* channel load by us is given in percentage */
+ chan_load_by_us =
+ NORMALIZE_PERCENT_TO_255(chan_load_by_us);
+
+ /* Use only values that firmware sends that can possibly be valid */
+ if (chan_load_by_us <= chan_load)
+ chan_load -= chan_load_by_us;
+
+ return chan_load;
+}
+
+static unsigned int
+iwl_mld_get_default_chan_load(struct ieee80211_bss_conf *link_conf)
+{
+ enum nl80211_band band = link_conf->chanreq.oper.chan->band;
+
+ switch (band) {
+ case NL80211_BAND_2GHZ:
+ return DEFAULT_CHAN_LOAD_2GHZ;
+ case NL80211_BAND_5GHZ:
+ return DEFAULT_CHAN_LOAD_5GHZ;
+ case NL80211_BAND_6GHZ:
+ return DEFAULT_CHAN_LOAD_6GHZ;
+ default:
+ WARN_ON(1);
+ return 0;
+ }
+}
+
+static unsigned int
+iwl_mld_get_chan_load(struct iwl_mld *mld,
+ struct ieee80211_bss_conf *link_conf)
+{
+ int chan_load;
+
+ chan_load = iwl_mld_get_chan_load_by_others(mld, link_conf);
+ if (chan_load >= 0)
+ return chan_load;
+
+ /* No information from the element, take the defaults */
+ chan_load = iwl_mld_get_default_chan_load(link_conf);
+
+ /* The defaults are given in percentage */
+ return NORMALIZE_PERCENT_TO_255(chan_load);
+}
+
+static unsigned int
+iwl_mld_get_avail_chan_load(struct iwl_mld *mld,
+ struct ieee80211_bss_conf *link_conf)
+{
+ return MAX_CHAN_LOAD - iwl_mld_get_chan_load(mld, link_conf);
+}
+
/* This function calculates the grade of a link. Returns 0 in error case */
unsigned int iwl_mld_get_link_grade(struct iwl_mld *mld,
struct ieee80211_bss_conf *link_conf)
@@ -754,7 +877,7 @@
}
/* Apply the channel load and puncturing factors */
- /* TODO: task=EMLSR task=statistics */
+ grade = grade * iwl_mld_get_avail_chan_load(mld, link_conf) / SCALE_FACTOR;
grade = grade * iwl_mld_get_n_subchannels(link_conf);
IWL_DEBUG_EHT(mld, "Link %d's grade: %d\n", link_conf->link_id, grade);
diff --git a/versions b/versions
index c2482c2..0ae9075 100644
--- a/versions
+++ b/versions
@@ -2,4 +2,4 @@
BACKPORTED_KERNEL_VERSION="(see git)"
BACKPORTED_KERNEL_NAME="iwlwifi"
BACKPORTS_BUILD_TSTAMP=__DATE__ \" \" __TIME__
-BACKPORTS_GIT_TRACKED="iwlwifi-stack-public:master:13353:6b452a66"
+BACKPORTS_GIT_TRACKED="iwlwifi-stack-public:master:13354:2319e6a6"
