Re: [PATCHv2 ath-next] wifi: ath11k: use kzalloc_flex

On 4/22/2026 4:42 AM, Rosen Penev wrote:
> Convert kzalloc_obj + kcalloc to kzalloc_flex to save an allocation.
> 
> Add __counted_by to get extra runtime analysis. Move counting variable
> assignment immediately after allocation before any potential accesses.
> kzalloc_flex does this anyway for GCC >= 15.
> 
> Signed-off-by: Rosen Penev <[email protected]>
> ---
>   v2: reword counting variable comment.
>   drivers/net/wireless/ath/ath11k/mac.c | 71 ++++++++++-----------------
>   drivers/net/wireless/ath/ath11k/wmi.h |  2 +-
>   2 files changed, 28 insertions(+), 45 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
> index 4a68bb9ca4fa..b5f3d7221b5f 100644
> --- a/drivers/net/wireless/ath/ath11k/mac.c
> +++ b/drivers/net/wireless/ath/ath11k/mac.c
> @@ -4228,13 +4228,14 @@ static int ath11k_mac_op_hw_scan(struct ieee80211_hw *hw,
>   	if (ret)
>   		goto exit;
> 
> -	arg = kzalloc_obj(*arg);
> +	arg = kzalloc_flex(*arg, chan_list, req->n_channels);
> 
>   	if (!arg) {
>   		ret = -ENOMEM;
>   		goto exit;
>   	}
> 
> +	arg->num_chan = req->n_channels;
>   	ath11k_wmi_start_scan_init(ar, arg);
>   	arg->vdev_id = arvif->vdev_id;
>   	arg->scan_id = ATH11K_SCAN_ID;
> @@ -4262,38 +4263,27 @@ static int ath11k_mac_op_hw_scan(struct ieee80211_hw *hw,
>   		arg->scan_f_passive = 1;
>   	}
> 
> -	if (req->n_channels) {
> -		arg->num_chan = req->n_channels;
> -		arg->chan_list = kcalloc(arg->num_chan, sizeof(*arg->chan_list),
> -					 GFP_KERNEL);
> +	for (i = 0; i < arg->num_chan; i++) {
> +		if (test_bit(WMI_TLV_SERVICE_SCAN_CONFIG_PER_CHANNEL,
> +			     ar->ab->wmi_ab.svc_map)) {
> +			arg->chan_list[i] =
> +				u32_encode_bits(req->channels[i]->center_freq,
> +						WMI_SCAN_CONFIG_PER_CHANNEL_MASK);
> 
> -		if (!arg->chan_list) {
> -			ret = -ENOMEM;
> -			goto exit;
> -		}
> -
> -		for (i = 0; i < arg->num_chan; i++) {
> -			if (test_bit(WMI_TLV_SERVICE_SCAN_CONFIG_PER_CHANNEL,
> -				     ar->ab->wmi_ab.svc_map)) {
> -				arg->chan_list[i] =
> -					u32_encode_bits(req->channels[i]->center_freq,
> -							WMI_SCAN_CONFIG_PER_CHANNEL_MASK);
> -
> -				/* If NL80211_SCAN_FLAG_COLOCATED_6GHZ is set in scan
> -				 * flags, then scan all PSC channels in 6 GHz band and
> -				 * those non-PSC channels where RNR IE is found during
> -				 * the legacy 2.4/5 GHz scan.
> -				 * If NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set,
> -				 * then all channels in 6 GHz will be scanned.
> -				 */
> -				if (req->channels[i]->band == NL80211_BAND_6GHZ &&
> -				    req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ &&
> -				    !cfg80211_channel_is_psc(req->channels[i]))
> -					arg->chan_list[i] |=
> -						WMI_SCAN_CH_FLAG_SCAN_ONLY_IF_RNR_FOUND;
> -			} else {
> -				arg->chan_list[i] = req->channels[i]->center_freq;
> -			}
> +			/* If NL80211_SCAN_FLAG_COLOCATED_6GHZ is set in scan
> +			 * flags, then scan all PSC channels in 6 GHz band and
> +			 * those non-PSC channels where RNR IE is found during
> +			 * the legacy 2.4/5 GHz scan.
> +			 * If NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set,
> +			 * then all channels in 6 GHz will be scanned.
> +			 */
> +			if (req->channels[i]->band == NL80211_BAND_6GHZ &&
> +			    req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ &&
> +			    !cfg80211_channel_is_psc(req->channels[i]))
> +				arg->chan_list[i] |=
> +					WMI_SCAN_CH_FLAG_SCAN_ONLY_IF_RNR_FOUND;
> +		} else {
> +			arg->chan_list[i] = req->channels[i]->center_freq;
>   		}
>   	}
> 


the exit: label at the end of the function has kfree(arg->chan_list); 
which now must be removed.



--
Ramesh