wifi: ath12k: Decrease ath12k_sta_rc_update_wk() stack usage

Currently when building ath12k with llvm-18.1.7-x86_64 the following warning is
observed:

drivers/net/wireless/ath/ath12k/mac.c:4946:13: warning: stack frame size (1112) exceeds limit (1024) in 'ath12k_sta_rc_update_wk' [-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>
Link: https://patch.msgid.link/20241217202618.1329312-4-kvalo@kernel.org
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index 2a30a11903c5fd06359e7323ed134328f9ae2f22..10293e9c1d4904ec70302388f846b760a9e49d72 100644 (file)
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -4956,7 +4956,6 @@ static void ath12k_sta_rc_update_wk(struct wiphy *wiphy, struct wiphy_work *wk)
        u32 changed, bw, nss, smps, bw_prev;
        int err, num_vht_rates;
        const struct cfg80211_bitrate_mask *mask;
-       struct ath12k_wmi_peer_assoc_arg peer_arg;
        enum wmi_phy_mode peer_phymode;
        struct ath12k_link_sta *arsta;
        struct ieee80211_vif *vif;
@@ -4992,9 +4991,14 @@ static void ath12k_sta_rc_update_wk(struct wiphy *wiphy, struct wiphy_work *wk)
        nss = min(nss, max(ath12k_mac_max_ht_nss(ht_mcs_mask),
                           ath12k_mac_max_vht_nss(vht_mcs_mask)));
 
+       struct ath12k_wmi_peer_assoc_arg *peer_arg __free(kfree) =
+                                       kzalloc(sizeof(*peer_arg), GFP_KERNEL);
+       if (!peer_arg)
+               return;
+
        if (changed & IEEE80211_RC_BW_CHANGED) {
-               ath12k_peer_assoc_h_phymode(ar, arvif, arsta, &peer_arg);
-               peer_phymode = peer_arg.peer_phymode;
+               ath12k_peer_assoc_h_phymode(ar, arvif, arsta, peer_arg);
+               peer_phymode = peer_arg->peer_phymode;
 
                if (bw > bw_prev) {
                        /* Phymode shows maximum supported channel width, if we
@@ -5096,9 +5100,9 @@ static void ath12k_sta_rc_update_wk(struct wiphy *wiphy, struct wiphy_work *wk)
                         * other rates using peer_assoc command.
                         */
                        ath12k_peer_assoc_prepare(ar, arvif, arsta,
-                                                 &peer_arg, true);
+                                                 peer_arg, true);
 
-                       err = ath12k_wmi_send_peer_assoc_cmd(ar, &peer_arg);
+                       err = ath12k_wmi_send_peer_assoc_cmd(ar, peer_arg);
                        if (err)
                                ath12k_warn(ar->ab, "failed to run peer assoc for STA %pM vdev %i: %d\n",
                                            arsta->addr, arvif->vdev_id, err);