Re: [PATCH] mwifiex: scan: Simplify code

From: Joe Perches
Date: Wed Aug 31 2016 - 11:09:25 EST


On Wed, 2016-08-31 at 13:50 +0200, Christophe JAILLET wrote:
> This patch:
>    - improves code layout
>    - removes a useless memset(0) for some memory allocated with kzalloc
>    - removes a useless if. We know that 'if (chan_band_tlv)' will succeed
>      because it has been tested a few lines above

True, the code above it is also confusing as it's

#ifdef CONFIG_PM
if (priv->wdev.wiphy->wowlan_config)
nd_config = priv->wdev.wiphy->wowlan_config->nd_config;
#endif

if (nd_config) {
adapter->nd_info =
kzalloc(sizeof(struct cfg80211_wowlan_nd_match) +
sizeof(struct cfg80211_wowlan_nd_match *) *
scan_rsp->number_of_sets, GFP_ATOMIC);

if (adapter->nd_info)
adapter->nd_info->n_matches = scan_rsp->number_of_sets;
}
where nd_config is a pointer already initialized to NULL
so the #endif seems misplaced.

> diff --git a/drivers/net/wireless/marvell/mwifiex/scan.c b/drivers/net/wireless/marvell/mwifiex/scan.c
[]
> @@ -2179,18 +2179,14 @@ int mwifiex_ret_802_11_scan(struct mwifiex_private *priv,

>  
>   if (chan_band_tlv && adapter->nd_info) {
>   adapter->nd_info->matches[idx] =
> - kzalloc(sizeof(*pmatch) +
> - sizeof(u32), GFP_ATOMIC);
> + kzalloc(sizeof(*pmatch) + sizeof(u32),
> + GFP_ATOMIC);
>  
>   pmatch = adapter->nd_info->matches[idx];
>  
>   if (pmatch) {
> - memset(pmatch, 0, sizeof(*pmatch));
> - if (chan_band_tlv) {
> - pmatch->n_channels = 1;
> - pmatch->channels[0] =
> - chan_band->chan_number;
> - }
> + pmatch->n_channels = 1;
> + pmatch->channels[0] = chan_band->chan_number;
>   }
>   }

Maybe it'd be better to move the pmatch declaration to this block
and alloc to pmatch then assign adapter->nd_info->matches[idx]
later.

I think the #ifdef CONFIG_PM use in this routine is incomplete.