[PATCH ath12k-ng] wifi: ath12k: move firmware stats request outside of atomic context

[Baochen Qiang]

In ath12k_mac_op_link_sta_statistics(), the atomic context scope
introduced by dp_lock also covers firmware stats request. Since that
request could block, below issue is hit:

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:575
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6866, name: iw
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
3 locks held by iw/6866:
 #0:[...]
 #1:[...]
 #2: ffff9748f43230c8 (&dp->dp_lock){+.-.}-{3:3}, at:
ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Preemption disabled at:
[<ffffffffc0349656>] ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Call Trace:
 <TASK>
 show_stack
 dump_stack_lvl
 dump_stack
 __might_resched.cold
 __might_sleep
 __mutex_lock
 mutex_lock_nested
 ath12k_mac_get_fw_stats
 ath12k_mac_op_link_sta_statistics
 </TASK>

Since firmware stats request doesn't require protection from dp_lock, move
it outside to fix this issue.

While moving, also refine that code hunk to make function parameters get
populated when really necessary.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3

Signed-off-by: Baochen Qiang <baochen.qiang at oss.qualcomm.com>
---
 drivers/net/wireless/ath/ath12k/mac.c | 44 ++++++++++++++++++-----------------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index aa80afebb69e..3649f58fef84 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -12792,10 +12792,12 @@ void ath12k_mac_op_link_sta_statistics(struct ieee80211_hw *hw,
 	db2dbm = test_bit(WMI_TLV_SERVICE_HW_DB2DBM_CONVERSION_SUPPORT,
 			  ar->ab->wmi_ab.svc_map);
 
-	guard(spinlock_bh)(&ar->ab->dp->dp_lock);
+	spin_lock_bh(&ar->ab->dp->dp_lock);
 	peer = ath12k_dp_link_peer_find_by_addr(ar->ab->dp, arsta->addr);
-	if (!peer)
+	if (!peer) {
+		spin_unlock_bh(&ar->ab->dp->dp_lock);
 		return;
+	}
 
 	link_sinfo->rx_duration = peer->rx_duration;
 	link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_DURATION);
@@ -12822,35 +12824,35 @@ void ath12k_mac_op_link_sta_statistics(struct ieee80211_hw *hw,
 		link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BITRATE);
 	}
 
+	link_sinfo->signal_avg = ewma_avg_rssi_read(&peer->avg_rssi);
+	if (!db2dbm)
+		link_sinfo->signal_avg += ATH12K_DEFAULT_NOISE_FLOOR;
+	link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG);
+
+	link_sinfo->tx_retries = peer->tx_retry_count;
+	link_sinfo->tx_failed = peer->tx_retry_failed;
+	link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_RETRIES);
+	link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_FAILED);
+
 	/* TODO: Use real NF instead of default one. */
 	signal = peer->rssi_comb;
 
-	params.pdev_id = ar->pdev->pdev_id;
-	params.vdev_id = 0;
-	params.stats_id = WMI_REQUEST_VDEV_STAT;
+	spin_unlock_bh(&ar->ab->dp->dp_lock);
 
-	if (!signal &&
-	    ahsta->ahvif->vdev_type == WMI_VDEV_TYPE_STA &&
-	    !(ath12k_mac_get_fw_stats(ar, &params)))
-		signal = arsta->rssi_beacon;
+	if (!signal && ahsta->ahvif->vdev_type == WMI_VDEV_TYPE_STA) {
+		params.pdev_id = ar->pdev->pdev_id;
+		params.vdev_id = 0;
+		params.stats_id = WMI_REQUEST_VDEV_STAT;
+
+		if (!ath12k_mac_get_fw_stats(ar, &params))
+			signal = arsta->rssi_beacon;
+	}
 
 	if (signal) {
 		link_sinfo->signal =
 			db2dbm ? signal : signal + ATH12K_DEFAULT_NOISE_FLOOR;
 		link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL);
 	}
-
-	link_sinfo->signal_avg = ewma_avg_rssi_read(&peer->avg_rssi);
-
-	if (!db2dbm)
-		link_sinfo->signal_avg += ATH12K_DEFAULT_NOISE_FLOOR;
-
-	link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG);
-
-	link_sinfo->tx_retries = peer->tx_retry_count;
-	link_sinfo->tx_failed = peer->tx_retry_failed;
-	link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_RETRIES);
-	link_sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_FAILED);
 }
 EXPORT_SYMBOL(ath12k_mac_op_link_sta_statistics);
 

---
base-commit: 7cd7392a07782b8ad4aa6360e4be1967af2eab04
change-id: 20251114-ath12k-ng-sleep-in-atomic-efebd6a7054b

Best regards,
-- 
Baochen Qiang <baochen.qiang at oss.qualcomm.com>