ath9k: make MAC sample statistics optional

They're more expensive than some of the other debug options and only used
in very rare situations, so it sometimes makes sense to disable them while
leaving in debugfs support.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/Kconfig

@@ -81,6 +81,14 @@ config ATH9K_DFS_CERTIFIED
 	  developed. At this point enabling this option won't do anything
 	  except increase code size.
 
+config ATH9K_MAC_DEBUG
+	bool "Atheros MAC statistics"
+	depends on ATH9K_DEBUGFS
+	default y
+	---help---
+	  This option enables collection of statistics for Rx/Tx status
+	  data and some other MAC related statistics
+
 config ATH9K_RATE_CONTROL
 	bool "Atheros ath9k rate control"
 	depends on ATH9K

drivers/net/wireless/ath/ath9k/debug.c

@@ -818,6 +818,7 @@ void ath_debug_stat_tx(struct ath_softc *sc, struct ath_buf *bf,
 	if (ts->ts_flags & ATH9K_TX_DELIM_UNDERRUN)
 		TX_STAT_INC(qnum, delim_underrun);
 
+#ifdef CONFIG_ATH9K_MAC_DEBUG
 	spin_lock(&sc->debug.samp_lock);
 	TX_SAMP_DBG(jiffies) = jiffies;
 	TX_SAMP_DBG(rssi_ctl0) = ts->ts_rssi_ctl0;
@@ -844,6 +845,7 @@ void ath_debug_stat_tx(struct ath_softc *sc, struct ath_buf *bf,
 
 	sc->debug.tsidx = (sc->debug.tsidx + 1) % ATH_DBG_MAX_SAMPLES;
 	spin_unlock(&sc->debug.samp_lock);
+#endif
 
 #undef TX_SAMP_DBG
 }
@@ -1019,6 +1021,7 @@ void ath_debug_stat_rx(struct ath_softc *sc, struct ath_rx_status *rs)
 
 	sc->debug.stats.rxstats.rs_antenna = rs->rs_antenna;
 
+#ifdef CONFIG_ATH9K_MAC_DEBUG
 	spin_lock(&sc->debug.samp_lock);
 	RX_SAMP_DBG(jiffies) = jiffies;
 	RX_SAMP_DBG(rssi_ctl0) = rs->rs_rssi_ctl0;
@@ -1035,6 +1038,8 @@ void ath_debug_stat_rx(struct ath_softc *sc, struct ath_rx_status *rs)
 	sc->debug.rsidx = (sc->debug.rsidx + 1) % ATH_DBG_MAX_SAMPLES;
 	spin_unlock(&sc->debug.samp_lock);
 
+#endif
+
 #undef RX_STAT_INC
 #undef RX_PHY_ERR_INC
 #undef RX_SAMP_DBG
@@ -1278,6 +1283,8 @@ static const struct file_operations fops_modal_eeprom = {
 	.llseek = default_llseek,
 };
 
+#ifdef CONFIG_ATH9K_MAC_DEBUG
+
 void ath9k_debug_samp_bb_mac(struct ath_softc *sc)
 {
 #define ATH_SAMP_DBG(c) (sc->debug.bb_mac_samp[sc->debug.sampidx].c)
@@ -1551,6 +1558,7 @@ static const struct file_operations fops_samps = {
 	.llseek = default_llseek,
 };
 
+#endif
 
 int ath9k_init_debug(struct ath_hw *ah)
 {
@@ -1604,8 +1612,10 @@ int ath9k_init_debug(struct ath_hw *ah)
 			    &fops_base_eeprom);
 	debugfs_create_file("modal_eeprom", S_IRUSR, sc->debug.debugfs_phy, sc,
 			    &fops_modal_eeprom);
+#ifdef CONFIG_ATH9K_MAC_DEBUG
 	debugfs_create_file("samples", S_IRUSR, sc->debug.debugfs_phy, sc,
 			    &fops_samps);
+#endif
 
 	debugfs_create_u32("gpio_mask", S_IRUSR | S_IWUSR,
 			   sc->debug.debugfs_phy, &sc->sc_ah->gpio_mask);

drivers/net/wireless/ath/ath9k/debug.h

@@ -235,16 +235,17 @@ struct ath9k_debug {
 	struct dentry *debugfs_phy;
 	u32 regidx;
 	struct ath_stats stats;
+#ifdef CONFIG_ATH9K_MAC_DEBUG
 	spinlock_t samp_lock;
 	struct ath_dbg_bb_mac_samp bb_mac_samp[ATH_DBG_MAX_SAMPLES];
 	u8 sampidx;
 	u8 tsidx;
 	u8 rsidx;
+#endif
 };
 
 int ath9k_init_debug(struct ath_hw *ah);
 
-void ath9k_debug_samp_bb_mac(struct ath_softc *sc);
 void ath_debug_stat_interrupt(struct ath_softc *sc, enum ath9k_int status);
 void ath_debug_stat_tx(struct ath_softc *sc, struct ath_buf *bf,
 		       struct ath_tx_status *ts, struct ath_txq *txq,
@@ -258,10 +259,6 @@ static inline int ath9k_init_debug(struct ath_hw *ah)
 	return 0;
 }
 
-static inline void ath9k_debug_samp_bb_mac(struct ath_softc *sc)
-{
-}
-
 static inline void ath_debug_stat_interrupt(struct ath_softc *sc,
 					    enum ath9k_int status)
 {
@@ -282,4 +279,17 @@ static inline void ath_debug_stat_rx(struct ath_softc *sc,
 
 #endif /* CONFIG_ATH9K_DEBUGFS */
 
+#ifdef CONFIG_ATH9K_MAC_DEBUG
+
+void ath9k_debug_samp_bb_mac(struct ath_softc *sc);
+
+#else
+
+static inline void ath9k_debug_samp_bb_mac(struct ath_softc *sc)
+{
+}
+
+#endif
+
+
 #endif /* DEBUG_H */

drivers/net/wireless/ath/ath9k/init.c

@@ -555,8 +555,10 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
 	mutex_init(&sc->mutex);
 #ifdef CONFIG_ATH9K_DEBUGFS
 	spin_lock_init(&sc->nodes_lock);
-	spin_lock_init(&sc->debug.samp_lock);
 	INIT_LIST_HEAD(&sc->nodes);
+#endif
+#ifdef CONFIG_ATH9K_MAC_DEBUG
+	spin_lock_init(&sc->debug.samp_lock);
 #endif
 	tasklet_init(&sc->intr_tq, ath9k_tasklet, (unsigned long)sc);
 	tasklet_init(&sc->bcon_tasklet, ath_beacon_tasklet,