[PATCH v2] wifi: ath9k: count spectral samples in the driver's own RX stats

[Nerijus Bendžiūnas]

ath_cmn_process_fft() is shared by ath9k and ath9k_htc, but it casts
common->priv to struct ath_softc to reach the rx_spectral_sample_good
and rx_spectral_sample_err counters. On ath9k_htc common->priv is a
struct ath9k_htc_priv, and with CONFIG_ATH9K_DEBUGFS the increment
lands far past the end of that allocation, once per FFT sample. On
x86-64 with a distribution config the structure is 2664 bytes and the
counters sit at offset 11912 of struct ath_softc.

Store a pointer to the driver's struct ath_rx_stats in struct
ath_spec_scan_priv and count through it. Both drivers pass their own
stats to ath9k_cmn_spectral_init_debug(), and both print them in the
shared recv debugfs file, so the two counters now also work on
ath9k_htc. A pointer keeps the common code free of driver structures,
which a check on the driver type would not. Without debugfs the
pointer stays NULL and nothing is counted, as before.

Fixes: 03224678c013 ("ath9k: add counters for good and errorneous FFT/spectral frames")
Cc: stable@xxxxxxxxxxxxxxx
Assisted-by: Claude:claude-fable-5-1
Signed-off-by: Nerijus Bendžiūnas <nerijus.bendziunas@xxxxxxxxx>
---
Changes in v2:
- Say where the quoted sizes come from and why a stats pointer rather
  than a check on the driver type.
- Add Assisted-by, rewrite the commit message, rebase onto ath-next. No
  code change.

 .../net/wireless/ath/ath9k/common-spectral.c  | 29 ++++++++++++-------
 .../net/wireless/ath/ath9k/common-spectral.h  | 11 +++++--
 drivers/net/wireless/ath/ath9k/debug.c        |  3 +-
 .../net/wireless/ath/ath9k/htc_drv_debug.c    |  3 +-
 4 files changed, 32 insertions(+), 14 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/common-spectral.c b/drivers/net/wireless/ath/ath9k/common-spectral.c
index ca01a07f6630..d8be24ebcd24 100644
--- a/drivers/net/wireless/ath/ath9k/common-spectral.c
+++ b/drivers/net/wireless/ath/ath9k/common-spectral.c
@@ -465,6 +465,20 @@ ath_cmn_is_fft_buf_full(struct ath_spec_scan_priv *spec_priv)
 		return 0;
 }
 
+static void ath_cmn_count_fft_sample(struct ath_spec_scan_priv *spec_priv,
+				     int ret)
+{
+	struct ath_rx_stats *rx_stats = spec_priv->rx_stats;
+
+	if (!rx_stats)
+		return;
+
+	if (ret == 0)
+		rx_stats->rx_spectral_sample_good++;
+	else
+		rx_stats->rx_spectral_sample_err++;
+}
+
 /* returns 1 if this was a spectral frame, even if not handled. */
 int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_hdr *hdr,
 		    struct ath_rx_status *rs, u64 tsf)
@@ -472,7 +486,6 @@ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_h
 	u8 sample_buf[SPECTRAL_SAMPLE_MAX_LEN] = {0};
 	struct ath_hw *ah = spec_priv->ah;
 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
-	struct ath_softc *sc = common->priv;
 	u8 num_bins, *vdata = (u8 *)hdr;
 	struct ath_radar_info *radar_info;
 	int len = rs->rs_datalen;
@@ -624,10 +637,7 @@ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_h
 				ret = fft_handler(rs, spec_priv, sample_buf,
 						  tsf, freq, chan_type);
 
-				if (ret == 0)
-					RX_STAT_INC(sc, rx_spectral_sample_good);
-				else
-					RX_STAT_INC(sc, rx_spectral_sample_err);
+				ath_cmn_count_fft_sample(spec_priv, ret);
 
 				/* Mix the received bins to the /dev/random
 				 * pool
@@ -642,10 +652,7 @@ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_h
 				ret = fft_handler(rs, spec_priv, sample_start,
 						  tsf, freq, chan_type);
 
-				if (ret == 0)
-					RX_STAT_INC(sc, rx_spectral_sample_good);
-				else
-					RX_STAT_INC(sc, rx_spectral_sample_err);
+				ath_cmn_count_fft_sample(spec_priv, ret);
 
 				/* Mix the received bins to the /dev/random
 				 * pool
@@ -1052,8 +1059,10 @@ void ath9k_cmn_spectral_deinit_debug(struct ath_spec_scan_priv *spec_priv)
 EXPORT_SYMBOL(ath9k_cmn_spectral_deinit_debug);
 
 void ath9k_cmn_spectral_init_debug(struct ath_spec_scan_priv *spec_priv,
-				   struct dentry *debugfs_phy)
+				   struct dentry *debugfs_phy,
+				   struct ath_rx_stats *rx_stats)
 {
+	spec_priv->rx_stats = rx_stats;
 	spec_priv->rfs_chan_spec_scan = relay_open("spectral_scan",
 					    debugfs_phy,
 					    1024, 256, &rfs_spec_scan_cb,
diff --git a/drivers/net/wireless/ath/ath9k/common-spectral.h b/drivers/net/wireless/ath/ath9k/common-spectral.h
index 011d8ab8b974..0e2c7d6d3487 100644
--- a/drivers/net/wireless/ath/ath9k/common-spectral.h
+++ b/drivers/net/wireless/ath/ath9k/common-spectral.h
@@ -94,12 +94,16 @@ struct ath_ht20_40_fft_packet {
 	struct ath_radar_info radar_info;
 } __packed;
 
+struct ath_rx_stats;
+
 struct ath_spec_scan_priv {
 	struct ath_hw *ah;
 	/* relay(fs) channel for spectral scan */
 	struct rchan *rfs_chan_spec_scan;
 	enum spectral_mode spectral_mode;
 	struct ath_spec_scan spec_config;
+	/* driver's RX statistics to account samples into, if any */
+	struct ath_rx_stats *rx_stats;
 };
 
 #define SPECTRAL_HT20_40_TOTAL_DATA_LEN	(sizeof(struct ath_ht20_40_fft_packet))
@@ -169,7 +173,9 @@ static inline u8 spectral_bitmap_weight(u8 *bins)
 }
 
 #ifdef CONFIG_ATH9K_COMMON_SPECTRAL
-void ath9k_cmn_spectral_init_debug(struct ath_spec_scan_priv *spec_priv, struct dentry *debugfs_phy);
+void ath9k_cmn_spectral_init_debug(struct ath_spec_scan_priv *spec_priv,
+				   struct dentry *debugfs_phy,
+				   struct ath_rx_stats *rx_stats);
 void ath9k_cmn_spectral_deinit_debug(struct ath_spec_scan_priv *spec_priv);
 
 void ath9k_cmn_spectral_scan_trigger(struct ath_common *common,
@@ -181,7 +187,8 @@ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_h
 		    struct ath_rx_status *rs, u64 tsf);
 #else
 static inline void ath9k_cmn_spectral_init_debug(struct ath_spec_scan_priv *spec_priv,
-						 struct dentry *debugfs_phy)
+						 struct dentry *debugfs_phy,
+						 struct ath_rx_stats *rx_stats)
 {
 }
 
diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
index 74a0134075cf..042a4f542a94 100644
--- a/drivers/net/wireless/ath/ath9k/debug.c
+++ b/drivers/net/wireless/ath/ath9k/debug.c
@@ -1389,7 +1389,8 @@ int ath9k_init_debug(struct ath_hw *ah)
 
 	ath9k_dfs_init_debug(sc);
 	ath9k_tx99_init_debug(sc);
-	ath9k_cmn_spectral_init_debug(&sc->spec_priv, sc->debug.debugfs_phy);
+	ath9k_cmn_spectral_init_debug(&sc->spec_priv, sc->debug.debugfs_phy,
+				      &sc->debug.stats.rxstats);
 
 	debugfs_create_devm_seqfile(sc->dev, "dma", sc->debug.debugfs_phy,
 				    read_file_dma);
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_debug.c b/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
index 9437d69877cc..9d354b1d929c 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_debug.c
@@ -487,7 +487,8 @@ int ath9k_htc_init_debug(struct ath_hw *ah)
 	priv->debug.debugfs_phy = debugfs_create_dir(KBUILD_MODNAME,
 					     priv->hw->wiphy->debugfsdir);
 
-	ath9k_cmn_spectral_init_debug(&priv->spec_priv, priv->debug.debugfs_phy);
+	ath9k_cmn_spectral_init_debug(&priv->spec_priv, priv->debug.debugfs_phy,
+				      &priv->debug.rx_stats);
 
 	debugfs_create_file("tgt_int_stats", 0400, priv->debug.debugfs_phy,
 			    priv, &fops_tgt_int_stats);

base-commit: 1d8e73163ef933624341075f576e2f36ef9133f7
-- 
2.55.0