[PATCH 2/4] wifi: ath12k: Decrease ath12k_bss_assoc() stack usage

Kalle Valo
2024-12-17T20:26:25Z

Currently when building ath12k with gcc-14.2.0 the following warning
is observed:

drivers/net/wireless/ath/ath12k/mac.c: In function 'ath12k_bss_assoc':
drivers/net/wireless/ath/ath12k/mac.c:3080:1: warning: the frame size of 1040 bytes is larger than 1024 bytes [-Wframe-larger-than=]

A major contributor to the stack usage in this function is:

struct ath12k_wmi_peer_assoc_arg peer_arg;

Avoid the excess stack usage by dynamically allocating peer_arg
instead of declaring it on the stack.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
---
drivers/net/wireless/ath/ath12k/mac.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index 05d2c75e5df2..2a30a11903c5 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -3133,7 +3133,6 @@ static void ath12k_bss_assoc(struct ath12k *ar,
struct ath12k_vif *ahvif = arvif->ahvif;
struct ieee80211_vif *vif = ath12k_ahvif_to_vif(ahvif);
struct ath12k_wmi_vdev_up_params params = {};
- struct ath12k_wmi_peer_assoc_arg peer_arg = {};
struct ieee80211_link_sta *link_sta;
u8 link_id = bss_conf->link_id;
struct ath12k_link_sta *arsta;
@@ -3145,6 +3144,11 @@ static void ath12k_bss_assoc(struct ath12k *ar,

lockdep_assert_wiphy(ath12k_ar_to_hw(ar)->wiphy);

+ struct ath12k_wmi_peer_assoc_arg *peer_arg __free(kfree) =
+ kzalloc(sizeof(*peer_arg), GFP_KERNEL);
+ if (!peer_arg)
+ return;
+
ath12k_dbg(ar->ab, ATH12K_DBG_MAC,
"mac vdev %i link id %u assoc bssid %pM aid %d\n",
arvif->vdev_id, link_id, arvif->bssid, ahvif->aid);
@@ -3177,11 +3181,11 @@ static void ath12k_bss_assoc(struct ath12k *ar,
return;
}

- ath12k_peer_assoc_prepare(ar, arvif, arsta, &peer_arg, false);
+ ath12k_peer_assoc_prepare(ar, arvif, arsta, peer_arg, false);

rcu_read_unlock();

- ret = ath12k_wmi_send_peer_assoc_cmd(ar, &peer_arg);
+ ret = ath12k_wmi_send_peer_assoc_cmd(ar, peer_arg);
if (ret) {
ath12k_warn(ar->ab, "failed to run peer assoc for %pM vdev %i: %d\n",
bss_conf->bssid, arvif->vdev_id, ret);
--
2.39.5