[PATCH ath-next v2] wifi: ath12k: avoid dynamic alloc when parsing wmi tb

[PATCH ath-next v2] wifi: ath12k: avoid dynamic alloc when parsing wmi tb

[Nicolas Escande]

On each WMI message received from the hardware, we alloc a temporary array
of WMI_TAG_MAX entries of type void *. This array is then populated with
pointers of parsed structs depending on the WMI type, and then freed. This
alloc can fail when memory pressure in the system is high enough.

Given the fact that it is scheduled in softirq with the system_bh_wq, we
should not be able to parse more than one WMI message per CPU at any time.

So instead lets move to a per cpu allocated array, that is reused across
calls: ath12K_wmi_tb that is global to the ath12K module. To alloc & free
we added two new module_init/exit functions for this module.

ath12k_wmi_tlv_parse_alloc() and ath12k_wmi_tlv_parse() are merged
together as it no longer allocs mem but returns the existing per-cpu one.

Signed-off-by: Nicolas Escande <nico.escande@gmail.com>
---
Small note on the new ath12k_wmi_tb variable. It is located in core.c and
I did not exported it in core.h (nor is it exported with EXPORT_SYMBOL())
as it is only used in wmi.c and should not be used by sub modules like
ath12k_wifi7.

changes from v1:
  - rebased on ath-next 27401c9b1432
  - changed wording according to Jeff's comment
  - moved alloc/cleanup to new module_init/exit functions in the
    ath12k module as per Baochen's comment

changes from RFC:
  - rebased on ath-next 8e0ab5b9adb7
  - converted missing call sites ath12k_wmi_obss_color_collision_event()
    & ath12k_wmi_pdev_temperature_event()
  - changed alloc order & cleanup path in ath12k_core_alloc() as it seems
    it confused people
  - used sizeof(*tb) in ath12k_wmi_tlv_parse()
---
 drivers/net/wireless/ath/ath12k/core.c |  22 +++
 drivers/net/wireless/ath/ath12k/core.h |   1 +
 drivers/net/wireless/ath/ath12k/wmi.c  | 181 ++++++-------------------
 3 files changed, 68 insertions(+), 136 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/core.c b/drivers/net/wireless/ath/ath12k/core.c
index c31c47fb5a73..c9a5baf41845 100644
--- a/drivers/net/wireless/ath/ath12k/core.c
+++ b/drivers/net/wireless/ath/ath12k/core.c
@@ -34,6 +34,8 @@ module_param_named(ftm_mode, ath12k_ftm_mode, bool, 0444);
 MODULE_PARM_DESC(ftm_mode, "Boots up in factory test mode");
 EXPORT_SYMBOL(ath12k_ftm_mode);
 
+void __percpu * ath12k_wmi_tb;
+
 /* protected with ath12k_hw_group_mutex */
 static struct list_head ath12k_hw_group_list = LIST_HEAD_INIT(ath12k_hw_group_list);
 
@@ -2321,5 +2323,25 @@ struct ath12k_base *ath12k_core_alloc(struct device *dev, size_t priv_size,
 	return NULL;
 }
 
+static int ath12k_init(void)
+{
+	ath12k_wmi_tb = __alloc_percpu(WMI_TAG_MAX * sizeof(void *),
+				       __alignof__(void *));
+	if (!ath12k_wmi_tb) {
+		pr_warn("Failed to alloc ath12k WMI tb\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void ath12k_exit(void)
+{
+	free_percpu(ath12k_wmi_tb);
+}
+
+module_init(ath12k_init);
+module_exit(ath12k_exit);
+
 MODULE_DESCRIPTION("Driver support for Qualcomm Technologies WLAN devices");
 MODULE_LICENSE("Dual BSD/GPL");
diff --git a/drivers/net/wireless/ath/ath12k/core.h b/drivers/net/wireless/ath/ath12k/core.h
index 59c193b24764..02ee6c718621 100644
--- a/drivers/net/wireless/ath/ath12k/core.h
+++ b/drivers/net/wireless/ath/ath12k/core.h
@@ -19,6 +19,7 @@
 #include <linux/average.h>
 #include <linux/of.h>
 #include <linux/rhashtable.h>
+#include <linux/percpu.h>
 #include "qmi.h"
 #include "htc.h"
 #include "wmi.h"
diff --git a/drivers/net/wireless/ath/ath12k/wmi.c b/drivers/net/wireless/ath/ath12k/wmi.c
index 8e13c3ec1cc7..7fae6c94a390 100644
--- a/drivers/net/wireless/ath/ath12k/wmi.c
+++ b/drivers/net/wireless/ath/ath12k/wmi.c
@@ -24,6 +24,8 @@
 #include "p2p.h"
 #include "testmode.h"
 
+extern void __percpu * ath12k_wmi_tb;
+
 struct ath12k_wmi_svc_ready_parse {
 	bool wmi_svc_bitmap_done;
 };
@@ -289,29 +291,19 @@ static int ath12k_wmi_tlv_iter_parse(struct ath12k_base *ab, u16 tag, u16 len,
 	return 0;
 }
 
-static int ath12k_wmi_tlv_parse(struct ath12k_base *ar, const void **tb,
-				const void *ptr, size_t len)
-{
-	return ath12k_wmi_tlv_iter(ar, ptr, len, ath12k_wmi_tlv_iter_parse,
-				   (void *)tb);
-}
-
 static const void **
-ath12k_wmi_tlv_parse_alloc(struct ath12k_base *ab,
-			   struct sk_buff *skb, gfp_t gfp)
+ath12k_wmi_tlv_parse(struct ath12k_base *ab, struct sk_buff *skb)
 {
 	const void **tb;
 	int ret;
 
-	tb = kzalloc_objs(*tb, WMI_TAG_MAX, gfp);
-	if (!tb)
-		return ERR_PTR(-ENOMEM);
+	tb = this_cpu_ptr(ath12k_wmi_tb);
+	memset(tb, 0, WMI_TAG_MAX * sizeof(*tb));
 
-	ret = ath12k_wmi_tlv_parse(ab, tb, skb->data, skb->len);
-	if (ret) {
-		kfree(tb);
+	ret = ath12k_wmi_tlv_iter(ab, skb->data, skb->len,
+				  ath12k_wmi_tlv_iter_parse, (void *)tb);
+	if (ret)
 		return ERR_PTR(ret);
-	}
 
 	return tb;
 }
@@ -3911,9 +3903,10 @@ ath12k_wmi_obss_color_collision_event(struct ath12k_base *ab, struct sk_buff *sk
 	const struct wmi_obss_color_collision_event *ev;
 	struct ath12k_link_vif *arvif;
 	u32 vdev_id, evt_type;
+	const void **tb;
 	u64 bitmap;
 
-	const void **tb __free(kfree) = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ath12k_warn(ab, "failed to parse OBSS color collision tlv %ld\n",
 			    PTR_ERR(tb));
@@ -5714,7 +5707,7 @@ static int ath12k_pull_vdev_start_resp_tlv(struct ath12k_base *ab, struct sk_buf
 	const struct wmi_vdev_start_resp_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -5724,13 +5717,11 @@ static int ath12k_pull_vdev_start_resp_tlv(struct ath12k_base *ab, struct sk_buf
 	ev = tb[WMI_TAG_VDEV_START_RESPONSE_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch vdev start resp ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
 	*vdev_rsp = *ev;
 
-	kfree(tb);
 	return 0;
 }
 
@@ -5809,7 +5800,7 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 
 	ath12k_dbg(ab, ATH12K_DBG_WMI, "processing regulatory ext channel list\n");
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -5819,7 +5810,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_REG_CHAN_LIST_CC_EXT_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch reg chan list ext update ev\n");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -5849,7 +5839,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 	if (num_2g_reg_rules > MAX_REG_RULES || num_5g_reg_rules > MAX_REG_RULES) {
 		ath12k_warn(ab, "Num reg rules for 2G/5G exceeds max limit (num_2g_reg_rules: %d num_5g_reg_rules: %d max_rules: %d)\n",
 			    num_2g_reg_rules, num_5g_reg_rules, MAX_REG_RULES);
-		kfree(tb);
 		return -EINVAL;
 	}
 
@@ -5859,7 +5848,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 		if (num_6g_reg_rules_ap[i] > MAX_6GHZ_REG_RULES) {
 			ath12k_warn(ab, "Num 6G reg rules for AP mode(%d) exceeds max limit (num_6g_reg_rules_ap: %d, max_rules: %d)\n",
 				    i, num_6g_reg_rules_ap[i], MAX_6GHZ_REG_RULES);
-			kfree(tb);
 			return -EINVAL;
 		}
 
@@ -5884,14 +5872,12 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 		    num_6g_reg_rules_cl[WMI_REG_VLP_AP][i] >  MAX_6GHZ_REG_RULES) {
 			ath12k_warn(ab, "Num 6g client reg rules exceeds max limit, for client(type: %d)\n",
 				    i);
-			kfree(tb);
 			return -EINVAL;
 		}
 	}
 
 	if (!total_reg_rules) {
 		ath12k_warn(ab, "No reg rules available\n");
-		kfree(tb);
 		return -EINVAL;
 	}
 
@@ -5993,7 +5979,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 						      ext_wmi_reg_rule);
 
 		if (!reg_info->reg_rules_2g_ptr) {
-			kfree(tb);
 			ath12k_warn(ab, "Unable to Allocate memory for 2g rules\n");
 			return -ENOMEM;
 		}
@@ -6027,7 +6012,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 						      ext_wmi_reg_rule);
 
 		if (!reg_info->reg_rules_5g_ptr) {
-			kfree(tb);
 			ath12k_warn(ab, "Unable to Allocate memory for 5g rules\n");
 			return -ENOMEM;
 		}
@@ -6046,7 +6030,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 						      ext_wmi_reg_rule);
 
 		if (!reg_info->reg_rules_6g_ap_ptr[i]) {
-			kfree(tb);
 			ath12k_warn(ab, "Unable to Allocate memory for 6g ap rules\n");
 			return -ENOMEM;
 		}
@@ -6061,7 +6044,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 							      ext_wmi_reg_rule);
 
 			if (!reg_info->reg_rules_6g_client_ptr[j][i]) {
-				kfree(tb);
 				ath12k_warn(ab, "Unable to Allocate memory for 6g client rules\n");
 				return -ENOMEM;
 			}
@@ -6096,7 +6078,6 @@ static int ath12k_pull_reg_chan_list_ext_update_ev(struct ath12k_base *ab,
 
 	ath12k_dbg(ab, ATH12K_DBG_WMI, "processed regulatory ext channel list\n");
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6107,7 +6088,7 @@ static int ath12k_pull_peer_del_resp_ev(struct ath12k_base *ab, struct sk_buff *
 	const struct wmi_peer_delete_resp_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6117,7 +6098,6 @@ static int ath12k_pull_peer_del_resp_ev(struct ath12k_base *ab, struct sk_buff *
 	ev = tb[WMI_TAG_PEER_DELETE_RESP_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch peer delete resp ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6127,7 +6107,6 @@ static int ath12k_pull_peer_del_resp_ev(struct ath12k_base *ab, struct sk_buff *
 	ether_addr_copy(peer_del_resp->peer_macaddr.addr,
 			ev->peer_macaddr.addr);
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6139,7 +6118,7 @@ static int ath12k_pull_vdev_del_resp_ev(struct ath12k_base *ab,
 	const struct wmi_vdev_delete_resp_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6149,13 +6128,11 @@ static int ath12k_pull_vdev_del_resp_ev(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_VDEV_DELETE_RESP_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch vdev delete resp ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
 	*vdev_id = le32_to_cpu(ev->vdev_id);
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6167,7 +6144,7 @@ static int ath12k_pull_bcn_tx_status_ev(struct ath12k_base *ab,
 	const struct wmi_bcn_tx_status_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6177,14 +6154,12 @@ static int ath12k_pull_bcn_tx_status_ev(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_OFFLOAD_BCN_TX_STATUS_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch bcn tx status ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
 	*vdev_id = le32_to_cpu(ev->vdev_id);
 	*tx_status = le32_to_cpu(ev->tx_status);
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6195,7 +6170,7 @@ static int ath12k_pull_vdev_stopped_param_tlv(struct ath12k_base *ab, struct sk_
 	const struct wmi_vdev_stopped_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6205,13 +6180,11 @@ static int ath12k_pull_vdev_stopped_param_tlv(struct ath12k_base *ab, struct sk_
 	ev = tb[WMI_TAG_VDEV_STOPPED_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch vdev stop ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
 	*vdev_id = le32_to_cpu(ev->vdev_id);
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6350,7 +6323,7 @@ static int ath12k_pull_mgmt_tx_compl_param_tlv(struct ath12k_base *ab,
 	const struct wmi_mgmt_tx_compl_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6360,7 +6333,6 @@ static int ath12k_pull_mgmt_tx_compl_param_tlv(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_MGMT_TX_COMPL_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch mgmt tx compl ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6370,7 +6342,6 @@ static int ath12k_pull_mgmt_tx_compl_param_tlv(struct ath12k_base *ab,
 	param->ppdu_id = ev->ppdu_id;
 	param->ack_rssi = ev->ack_rssi;
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6533,7 +6504,7 @@ static int ath12k_pull_scan_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	const struct wmi_scan_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6543,7 +6514,6 @@ static int ath12k_pull_scan_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	ev = tb[WMI_TAG_SCAN_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch scan ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6555,7 +6525,6 @@ static int ath12k_pull_scan_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	scan_evt_param->vdev_id = ev->vdev_id;
 	scan_evt_param->tsf_timestamp = ev->tsf_timestamp;
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6566,7 +6535,7 @@ static int ath12k_pull_peer_sta_kickout_ev(struct ath12k_base *ab, struct sk_buf
 	const struct wmi_peer_sta_kickout_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6576,7 +6545,6 @@ static int ath12k_pull_peer_sta_kickout_ev(struct ath12k_base *ab, struct sk_buf
 	ev = tb[WMI_TAG_PEER_STA_KICKOUT_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch peer sta kickout ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6584,7 +6552,6 @@ static int ath12k_pull_peer_sta_kickout_ev(struct ath12k_base *ab, struct sk_buf
 	arg->reason = le32_to_cpu(ev->reason);
 	arg->rssi = le32_to_cpu(ev->rssi);
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6595,7 +6562,7 @@ static int ath12k_pull_roam_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	const struct wmi_roam_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6605,7 +6572,6 @@ static int ath12k_pull_roam_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	ev = tb[WMI_TAG_ROAM_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch roam ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6613,7 +6579,6 @@ static int ath12k_pull_roam_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	roam_ev->reason = ev->reason;
 	roam_ev->rssi = ev->rssi;
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6647,7 +6612,7 @@ static int ath12k_pull_chan_info_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	const struct wmi_chan_info_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6657,7 +6622,6 @@ static int ath12k_pull_chan_info_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	ev = tb[WMI_TAG_CHAN_INFO_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch chan info ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6674,7 +6638,6 @@ static int ath12k_pull_chan_info_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	ch_info_ev->mac_clk_mhz = ev->mac_clk_mhz;
 	ch_info_ev->vdev_id = ev->vdev_id;
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6686,7 +6649,7 @@ ath12k_pull_pdev_bss_chan_info_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	const struct wmi_pdev_bss_chan_info_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6696,7 +6659,6 @@ ath12k_pull_pdev_bss_chan_info_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	ev = tb[WMI_TAG_PDEV_BSS_CHAN_INFO_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch pdev bss chan info ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6714,7 +6676,6 @@ ath12k_pull_pdev_bss_chan_info_ev(struct ath12k_base *ab, struct sk_buff *skb,
 	bss_ch_info_ev->rx_bss_cycle_count_low = ev->rx_bss_cycle_count_low;
 	bss_ch_info_ev->rx_bss_cycle_count_high = ev->rx_bss_cycle_count_high;
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6726,7 +6687,7 @@ ath12k_pull_vdev_install_key_compl_ev(struct ath12k_base *ab, struct sk_buff *sk
 	const struct wmi_vdev_install_key_compl_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6736,7 +6697,6 @@ ath12k_pull_vdev_install_key_compl_ev(struct ath12k_base *ab, struct sk_buff *sk
 	ev = tb[WMI_TAG_VDEV_INSTALL_KEY_COMPLETE_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch vdev install key compl ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
@@ -6746,7 +6706,6 @@ ath12k_pull_vdev_install_key_compl_ev(struct ath12k_base *ab, struct sk_buff *sk
 	arg->key_flags = le32_to_cpu(ev->key_flags);
 	arg->status = le32_to_cpu(ev->status);
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6757,7 +6716,7 @@ static int ath12k_pull_peer_assoc_conf_ev(struct ath12k_base *ab, struct sk_buff
 	const struct wmi_peer_assoc_conf_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6767,14 +6726,12 @@ static int ath12k_pull_peer_assoc_conf_ev(struct ath12k_base *ab, struct sk_buff
 	ev = tb[WMI_TAG_PEER_ASSOC_CONF_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch peer assoc conf ev");
-		kfree(tb);
 		return -EPROTO;
 	}
 
 	peer_assoc_conf->vdev_id = le32_to_cpu(ev->vdev_id);
 	peer_assoc_conf->macaddr = ev->peer_macaddr.addr;
 
-	kfree(tb);
 	return 0;
 }
 
@@ -6792,7 +6749,7 @@ static int ath12k_reg_11d_new_cc_event(struct ath12k_base *ab, struct sk_buff *s
 	const void **tb;
 	int ret, i;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -6801,7 +6758,6 @@ static int ath12k_reg_11d_new_cc_event(struct ath12k_base *ab, struct sk_buff *s
 
 	ev = tb[WMI_TAG_11D_NEW_COUNTRY_EVENT];
 	if (!ev) {
-		kfree(tb);
 		ath12k_warn(ab, "failed to fetch 11d new cc ev");
 		return -EPROTO;
 	}
@@ -6814,8 +6770,6 @@ static int ath12k_reg_11d_new_cc_event(struct ath12k_base *ab, struct sk_buff *s
 		   ab->new_alpha2[0],
 		   ab->new_alpha2[1]);
 
-	kfree(tb);
-
 	for (i = 0; i < ab->num_radios; i++) {
 		pdev = &ab->pdevs[i];
 		ar = pdev->ar;
@@ -8567,7 +8521,7 @@ static void ath12k_pdev_ctl_failsafe_check_event(struct ath12k_base *ab,
 	const struct wmi_pdev_ctl_failsafe_chk_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -8577,7 +8531,6 @@ static void ath12k_pdev_ctl_failsafe_check_event(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_PDEV_CTL_FAILSAFE_CHECK_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch pdev ctl failsafe check ev");
-		kfree(tb);
 		return;
 	}
 
@@ -8591,8 +8544,6 @@ static void ath12k_pdev_ctl_failsafe_check_event(struct ath12k_base *ab,
 	if (ev->ctl_failsafe_status != 0)
 		ath12k_warn(ab, "pdev ctl failsafe failure status %d",
 			    ev->ctl_failsafe_status);
-
-	kfree(tb);
 }
 
 static void
@@ -8664,7 +8615,7 @@ ath12k_wmi_pdev_csa_switch_count_status_event(struct ath12k_base *ab,
 	const u32 *vdev_ids;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -8676,7 +8627,6 @@ ath12k_wmi_pdev_csa_switch_count_status_event(struct ath12k_base *ab,
 
 	if (!ev || !vdev_ids) {
 		ath12k_warn(ab, "failed to fetch pdev csa switch count ev");
-		kfree(tb);
 		return;
 	}
 
@@ -8686,8 +8636,6 @@ ath12k_wmi_pdev_csa_switch_count_status_event(struct ath12k_base *ab,
 		   ev->num_vdevs);
 
 	ath12k_wmi_process_csa_switch_count_event(ab, ev, vdev_ids);
-
-	kfree(tb);
 }
 
 static void
@@ -8699,7 +8647,7 @@ ath12k_wmi_pdev_dfs_radar_detected_event(struct ath12k_base *ab, struct sk_buff
 	struct ath12k *ar;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -8710,7 +8658,6 @@ ath12k_wmi_pdev_dfs_radar_detected_event(struct ath12k_base *ab, struct sk_buff
 
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch pdev dfs radar detected ev");
-		kfree(tb);
 		return;
 	}
 
@@ -8749,8 +8696,6 @@ ath12k_wmi_pdev_dfs_radar_detected_event(struct ath12k_base *ab, struct sk_buff
 
 exit:
 	rcu_read_unlock();
-
-	kfree(tb);
 }
 
 static void ath12k_tm_wmi_event_segmented(struct ath12k_base *ab, u32 cmd_id,
@@ -8761,7 +8706,7 @@ static void ath12k_tm_wmi_event_segmented(struct ath12k_base *ab, u32 cmd_id,
 	int ret;
 	u16 length;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
@@ -8772,14 +8717,11 @@ static void ath12k_tm_wmi_event_segmented(struct ath12k_base *ab, u32 cmd_id,
 	ev = tb[WMI_TAG_ARRAY_BYTE];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch ftm msg\n");
-		kfree(tb);
 		return;
 	}
 
 	length = skb->len - TLV_HDR_SIZE;
 	ath12k_tm_process_event(ab, cmd_id, ev, length);
-	kfree(tb);
-	tb = NULL;
 }
 
 static void
@@ -8792,7 +8734,7 @@ ath12k_wmi_pdev_temperature_event(struct ath12k_base *ab,
 	int temp;
 	u32 pdev_id;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ath12k_warn(ab, "failed to parse tlv: %ld\n", PTR_ERR(tb));
 		return;
@@ -8801,15 +8743,12 @@ ath12k_wmi_pdev_temperature_event(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_PDEV_TEMPERATURE_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch pdev temp ev\n");
-		kfree(tb);
 		return;
 	}
 
 	temp = a_sle32_to_cpu(ev->temp);
 	pdev_id = le32_to_cpu(ev->pdev_id);
 
-	kfree(tb);
-
 	ath12k_dbg(ab, ATH12K_DBG_WMI,
 		   "pdev temperature ev temp %d pdev_id %u\n",
 		   temp, pdev_id);
@@ -8836,7 +8775,7 @@ static void ath12k_fils_discovery_event(struct ath12k_base *ab,
 	const struct wmi_fils_discovery_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab,
@@ -8848,15 +8787,12 @@ static void ath12k_fils_discovery_event(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_HOST_SWFDA_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch FILS discovery event\n");
-		kfree(tb);
 		return;
 	}
 
 	ath12k_warn(ab,
 		    "FILS discovery frame expected from host for vdev_id: %u, transmission scheduled at %u, next TBTT: %u\n",
 		    ev->vdev_id, ev->fils_tt, ev->tbtt);
-
-	kfree(tb);
 }
 
 static void ath12k_probe_resp_tx_status_event(struct ath12k_base *ab,
@@ -8866,7 +8802,7 @@ static void ath12k_probe_resp_tx_status_event(struct ath12k_base *ab,
 	const struct wmi_probe_resp_tx_status_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab,
@@ -8879,7 +8815,6 @@ static void ath12k_probe_resp_tx_status_event(struct ath12k_base *ab,
 	if (!ev) {
 		ath12k_warn(ab,
 			    "failed to fetch probe response transmission status event");
-		kfree(tb);
 		return;
 	}
 
@@ -8887,8 +8822,6 @@ static void ath12k_probe_resp_tx_status_event(struct ath12k_base *ab,
 		ath12k_warn(ab,
 			    "Probe response transmission failed for vdev_id %u, status %u\n",
 			    ev->vdev_id, ev->tx_status);
-
-	kfree(tb);
 }
 
 static int ath12k_wmi_p2p_noa_event(struct ath12k_base *ab,
@@ -8900,7 +8833,7 @@ static int ath12k_wmi_p2p_noa_event(struct ath12k_base *ab,
 	struct ath12k *ar;
 	int ret, vdev_id;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse P2P NoA TLV: %d\n", ret);
@@ -8910,10 +8843,8 @@ static int ath12k_wmi_p2p_noa_event(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_P2P_NOA_EVENT];
 	noa = tb[WMI_TAG_P2P_NOA_INFO];
 
-	if (!ev || !noa) {
-		ret = -EPROTO;
-		goto out;
-	}
+	if (!ev || !noa)
+		return -EPROTO;
 
 	vdev_id = __le32_to_cpu(ev->vdev_id);
 
@@ -8936,8 +8867,6 @@ static int ath12k_wmi_p2p_noa_event(struct ath12k_base *ab,
 
 unlock:
 	rcu_read_unlock();
-out:
-	kfree(tb);
 	return ret;
 }
 
@@ -8948,7 +8877,7 @@ static void ath12k_rfkill_state_change_event(struct ath12k_base *ab,
 	const void **tb;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -8956,10 +8885,8 @@ static void ath12k_rfkill_state_change_event(struct ath12k_base *ab,
 	}
 
 	ev = tb[WMI_TAG_RFKILL_EVENT];
-	if (!ev) {
-		kfree(tb);
+	if (!ev)
 		return;
-	}
 
 	ath12k_dbg(ab, ATH12K_DBG_MAC,
 		   "wmi tlv rfkill state change gpio %d type %d radio_state %d\n",
@@ -8972,7 +8899,6 @@ static void ath12k_rfkill_state_change_event(struct ath12k_base *ab,
 	spin_unlock_bh(&ab->base_lock);
 
 	queue_work(ab->workqueue, &ab->rfkill_work);
-	kfree(tb);
 }
 
 static void
@@ -8988,7 +8914,7 @@ static void ath12k_wmi_twt_enable_event(struct ath12k_base *ab,
 	const struct wmi_twt_enable_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse wmi twt enable status event tlv: %d\n",
@@ -8999,15 +8925,12 @@ static void ath12k_wmi_twt_enable_event(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_TWT_ENABLE_COMPLETE_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch twt enable wmi event\n");
-		goto exit;
+		return;
 	}
 
 	ath12k_dbg(ab, ATH12K_DBG_MAC, "wmi twt enable event pdev id %u status %u\n",
 		   le32_to_cpu(ev->pdev_id),
 		   le32_to_cpu(ev->status));
-
-exit:
-	kfree(tb);
 }
 
 static void ath12k_wmi_twt_disable_event(struct ath12k_base *ab,
@@ -9017,7 +8940,7 @@ static void ath12k_wmi_twt_disable_event(struct ath12k_base *ab,
 	const struct wmi_twt_disable_event *ev;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse wmi twt disable status event tlv: %d\n",
@@ -9028,15 +8951,12 @@ static void ath12k_wmi_twt_disable_event(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_TWT_DISABLE_COMPLETE_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch twt disable wmi event\n");
-		goto exit;
+		return;
 	}
 
 	ath12k_dbg(ab, ATH12K_DBG_MAC, "wmi twt disable event pdev id %d status %u\n",
 		   le32_to_cpu(ev->pdev_id),
 		   le32_to_cpu(ev->status));
-
-exit:
-	kfree(tb);
 }
 
 static int ath12k_wmi_wow_wakeup_host_parse(struct ath12k_base *ab,
@@ -9109,7 +9029,7 @@ static void ath12k_wmi_gtk_offload_status_event(struct ath12k_base *ab,
 	const void **tb;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
@@ -9119,7 +9039,6 @@ static void ath12k_wmi_gtk_offload_status_event(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_GTK_OFFLOAD_STATUS_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch gtk offload status ev");
-		kfree(tb);
 		return;
 	}
 
@@ -9129,7 +9048,6 @@ static void ath12k_wmi_gtk_offload_status_event(struct ath12k_base *ab,
 		rcu_read_unlock();
 		ath12k_warn(ab, "failed to get arvif for vdev_id:%d\n",
 			    le32_to_cpu(ev->vdev_id));
-		kfree(tb);
 		return;
 	}
 
@@ -9145,8 +9063,6 @@ static void ath12k_wmi_gtk_offload_status_event(struct ath12k_base *ab,
 				   (void *)&replay_ctr_be, GFP_ATOMIC);
 
 	rcu_read_unlock();
-
-	kfree(tb);
 }
 
 static void ath12k_wmi_event_mlo_setup_complete(struct ath12k_base *ab,
@@ -9158,7 +9074,7 @@ static void ath12k_wmi_event_mlo_setup_complete(struct ath12k_base *ab,
 	const void **tb;
 	int ret, i;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse mlo setup complete event tlv: %d\n",
@@ -9169,7 +9085,6 @@ static void ath12k_wmi_event_mlo_setup_complete(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_MLO_SETUP_COMPLETE_EVENT];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch mlo setup complete event\n");
-		kfree(tb);
 		return;
 	}
 
@@ -9188,14 +9103,11 @@ static void ath12k_wmi_event_mlo_setup_complete(struct ath12k_base *ab,
 	if (!ar) {
 		ath12k_warn(ab, "invalid pdev_id %d status %u in setup complete event\n",
 			    ev->pdev_id, ev->status);
-		goto out;
+		return;
 	}
 
 	ar->mlo_setup_status = le32_to_cpu(ev->status);
 	complete(&ar->mlo_setup_done);
-
-out:
-	kfree(tb);
 }
 
 static void ath12k_wmi_event_teardown_complete(struct ath12k_base *ab,
@@ -9205,7 +9117,7 @@ static void ath12k_wmi_event_teardown_complete(struct ath12k_base *ab,
 	const void **tb;
 	int ret;
 
-	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	tb = ath12k_wmi_tlv_parse(ab, skb);
 	if (IS_ERR(tb)) {
 		ret = PTR_ERR(tb);
 		ath12k_warn(ab, "failed to parse teardown complete event tlv: %d\n", ret);
@@ -9215,11 +9127,8 @@ static void ath12k_wmi_event_teardown_complete(struct ath12k_base *ab,
 	ev = tb[WMI_TAG_MLO_TEARDOWN_COMPLETE];
 	if (!ev) {
 		ath12k_warn(ab, "failed to fetch teardown complete event\n");
-		kfree(tb);
 		return;
 	}
-
-	kfree(tb);
 }
 
 #ifdef CONFIG_ATH12K_DEBUGFS
-- 
2.53.0

Re: [PATCH ath-next v2] wifi: ath12k: avoid dynamic alloc when parsing wmi tb

[Baochen Qiang]

On 3/13/2026 7:38 PM, Nicolas Escande wrote:
> On each WMI message received from the hardware, we alloc a temporary array
> of WMI_TAG_MAX entries of type void *. This array is then populated with
> pointers of parsed structs depending on the WMI type, and then freed. This
> alloc can fail when memory pressure in the system is high enough.
> 
> Given the fact that it is scheduled in softirq with the system_bh_wq, we
> should not be able to parse more than one WMI message per CPU at any time.
> 
> So instead lets move to a per cpu allocated array, that is reused across
> calls: ath12K_wmi_tb that is global to the ath12K module. To alloc & free
> we added two new module_init/exit functions for this module.
> 
> ath12k_wmi_tlv_parse_alloc() and ath12k_wmi_tlv_parse() are merged
> together as it no longer allocs mem but returns the existing per-cpu one.
> 
> Signed-off-by: Nicolas Escande <nico.escande@gmail.com>
> ---
> Small note on the new ath12k_wmi_tb variable. It is located in core.c and
> I did not exported it in core.h (nor is it exported with EXPORT_SYMBOL())
> as it is only used in wmi.c and should not be used by sub modules like
> ath12k_wifi7.

agree

or alternately you can define ath12k_wmi_tb in wmi.c and add alloc/free functions in
wmi.c, then call them in core.c. this helps modularity IMO?

either way works for me!

> 
> changes from v1:
>   - rebased on ath-next 27401c9b1432
>   - changed wording according to Jeff's comment
>   - moved alloc/cleanup to new module_init/exit functions in the
>     ath12k module as per Baochen's comment
> 
> changes from RFC:
>   - rebased on ath-next 8e0ab5b9adb7
>   - converted missing call sites ath12k_wmi_obss_color_collision_event()
>     & ath12k_wmi_pdev_temperature_event()
>   - changed alloc order & cleanup path in ath12k_core_alloc() as it seems
>     it confused people
>   - used sizeof(*tb) in ath12k_wmi_tlv_parse()
> ---
>  drivers/net/wireless/ath/ath12k/core.c |  22 +++
>  drivers/net/wireless/ath/ath12k/core.h |   1 +
>  drivers/net/wireless/ath/ath12k/wmi.c  | 181 ++++++-------------------
>  3 files changed, 68 insertions(+), 136 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath12k/core.c b/drivers/net/wireless/ath/ath12k/core.c
> index c31c47fb5a73..c9a5baf41845 100644
> --- a/drivers/net/wireless/ath/ath12k/core.c
> +++ b/drivers/net/wireless/ath/ath12k/core.c
> @@ -34,6 +34,8 @@ module_param_named(ftm_mode, ath12k_ftm_mode, bool, 0444);
>  MODULE_PARM_DESC(ftm_mode, "Boots up in factory test mode");
>  EXPORT_SYMBOL(ath12k_ftm_mode);
>  
> +void __percpu * ath12k_wmi_tb;
> +
>  /* protected with ath12k_hw_group_mutex */
>  static struct list_head ath12k_hw_group_list = LIST_HEAD_INIT(ath12k_hw_group_list);
>  
> @@ -2321,5 +2323,25 @@ struct ath12k_base *ath12k_core_alloc(struct device *dev, size_t priv_size,
>  	return NULL;
>  }
>  
> +static int ath12k_init(void)
> +{
> +	ath12k_wmi_tb = __alloc_percpu(WMI_TAG_MAX * sizeof(void *),
> +				       __alignof__(void *));
> +	if (!ath12k_wmi_tb) {
> +		pr_warn("Failed to alloc ath12k WMI tb\n");

generally we don't log memory allocation failure

> +		return -ENOMEM;
> +	}
> +
> +	return 0;
> +}
> +
> +static void ath12k_exit(void)
> +{
> +	free_percpu(ath12k_wmi_tb);
> +}
> +
> +module_init(ath12k_init);
> +module_exit(ath12k_exit);
> +
>  MODULE_DESCRIPTION("Driver support for Qualcomm Technologies WLAN devices");
>  MODULE_LICENSE("Dual BSD/GPL");


[...]

> @@ -9205,7 +9117,7 @@ static void ath12k_wmi_event_teardown_complete(struct ath12k_base *ab,
>  	const void **tb;
>  	int ret;
>  
> -	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
> +	tb = ath12k_wmi_tlv_parse(ab, skb);
>  	if (IS_ERR(tb)) {
>  		ret = PTR_ERR(tb);
>  		ath12k_warn(ab, "failed to parse teardown complete event tlv: %d\n", ret);
> @@ -9215,11 +9127,8 @@ static void ath12k_wmi_event_teardown_complete(struct ath12k_base *ab,
>  	ev = tb[WMI_TAG_MLO_TEARDOWN_COMPLETE];
>  	if (!ev) {
>  		ath12k_warn(ab, "failed to fetch teardown complete event\n");
> -		kfree(tb);
>  		return;

nit: better to remove return as well

>  	}
> -
> -	kfree(tb);
>  }
>  
>  #ifdef CONFIG_ATH12K_DEBUGFS

Re: [PATCH ath-next v2] wifi: ath12k: avoid dynamic alloc when parsing wmi tb

[Nicolas Escande]

On Mon Mar 16, 2026 at 3:27 AM CET, Baochen Qiang wrote:
[...]
> or alternately you can define ath12k_wmi_tb in wmi.c and add alloc/free functions in
> wmi.c, then call them in core.c. this helps modularity IMO?

I'll add new functions to wmi.c and make ath12k_wmi_tb static to that file.
>
> either way works for me!
>
[...]
>> +static int ath12k_init(void)
>> +{
>> +	ath12k_wmi_tb = __alloc_percpu(WMI_TAG_MAX * sizeof(void *),
>> +				       __alignof__(void *));
>> +	if (!ath12k_wmi_tb) {
>> +		pr_warn("Failed to alloc ath12k WMI tb\n");
>
> generally we don't log memory allocation failure

sure will fix

>
>> +		return -ENOMEM;
>> +	}
>> +
>> +	return 0;
>> +}

[...]

>> @@ -9215,11 +9127,8 @@ static void ath12k_wmi_event_teardown_complete(struct ath12k_base *ab,
>>  	ev = tb[WMI_TAG_MLO_TEARDOWN_COMPLETE];
>>  	if (!ev) {
>>  		ath12k_warn(ab, "failed to fetch teardown complete event\n");
>> -		kfree(tb);
>>  		return;
>
> nit: better to remove return as well

Indeed this slipped through the cracks will fix

>
>>  	}
>> -
>> -	kfree(tb);
>>  }
>>  
>>  #ifdef CONFIG_ATH12K_DEBUGFS