iwlwifi: mvm: rs: don't zero tx stats after idle

Move the tx stats to the persistent area of lq_sta to
avoid them being zeroed out every time rs reinitializes
which happens after tx idle for 5 secs for example.
The automatic zeroing out made them difficult to use.
Signed-off-by: Eyal Shapira <eyalx.shapira@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

drivers/net/wireless/iwlwifi/mvm/rs.c

@@ -672,8 +672,10 @@ static int rs_collect_tx_data(struct iwl_lq_sta *lq_sta,
 		return -EINVAL;
 
 	if (tbl->column != RS_COLUMN_INVALID) {
-		lq_sta->tx_stats[tbl->column][scale_index].total += attempts;
-		lq_sta->tx_stats[tbl->column][scale_index].success += successes;
+		struct lq_sta_pers *pers = &lq_sta->pers;
+
+		pers->tx_stats[tbl->column][scale_index].total += attempts;
+		pers->tx_stats[tbl->column][scale_index].success += successes;
 	}
 
 	/* Select window for current tx bit rate */
@@ -3171,7 +3173,7 @@ static ssize_t rs_sta_dbgfs_drv_tx_stats_read(struct file *file,
 				 "%s,", column_name[col]);
 
 		for (rate = 0; rate < IWL_RATE_COUNT; rate++) {
-			stats = &(lq_sta->tx_stats[col][rate]);
+			stats = &(lq_sta->pers.tx_stats[col][rate]);
 			pos += scnprintf(pos, endpos - pos,
 					 "%llu/%llu,",
 					 stats->success,
@@ -3190,7 +3192,7 @@ static ssize_t rs_sta_dbgfs_drv_tx_stats_write(struct file *file,
 					       size_t count, loff_t *ppos)
 {
 	struct iwl_lq_sta *lq_sta = file->private_data;
-	memset(lq_sta->tx_stats, 0, sizeof(lq_sta->tx_stats));
+	memset(lq_sta->pers.tx_stats, 0, sizeof(lq_sta->pers.tx_stats));
 
 	return count;
 }

drivers/net/wireless/iwlwifi/mvm/rs.h

@@ -333,8 +333,6 @@ struct iwl_lq_sta {
 	bool ldpc;              /* LDPC Rx is supported by the STA */
 	enum ieee80211_band band;
 
-	struct rs_rate_stats tx_stats[RS_COLUMN_COUNT][IWL_RATE_COUNT];
-
 	/* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
 	unsigned long active_legacy_rate;
 	unsigned long active_siso_rate;
@@ -362,11 +360,14 @@ struct iwl_lq_sta {
 	int tpc_reduce;
 
 	/* persistent fields - initialized only once - keep last! */
-	struct {
+	struct lq_sta_pers {
 #ifdef CONFIG_MAC80211_DEBUGFS
 		u32 dbg_fixed_rate;
 		u8 dbg_fixed_txp_reduction;
 #endif
+		u8 chains;
+		s8 chain_signal[IEEE80211_MAX_CHAINS];
+		struct rs_rate_stats tx_stats[RS_COLUMN_COUNT][IWL_RATE_COUNT];
 		struct iwl_mvm *drv;
 	} pers;
 };