Re: [PATCH net-next] net: stmmac: Remove unused variable 'ret' at stmmac_rx_buf1_len()

[luojiaxing]

On 2020/9/11 3:29, Jakub Kicinski wrote:
> On Thu, 10 Sep 2020 10:42:45 +0800 Luo Jiaxing wrote:
> > Fixes the following warning when using W=1 to build kernel:
> >
> > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3634:6: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable]
> > int ret, coe = priv->hw->rx_csum;
> >
> > When digging stmmac_get_rx_header_len(), dwmac4_get_rx_header_len() and
> > dwxgmac2_get_rx_header_len() return 0 by default. Therefore, ret do not
> > need to check the error value and can be directly deleted.
> >
> > Signed-off-by: Luo Jiaxing <luojiaxing@xxxxxxxxxx>
> > ---
> >   drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++--
> >   1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > index 89b2b34..7e95412 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > @@ -3631,15 +3631,15 @@ static unsigned int stmmac_rx_buf1_len(struct stmmac_priv *priv,
> >   				       struct dma_desc *p,
> >   				       int status, unsigned int len)
> >   {
> > -	int ret, coe = priv->hw->rx_csum;
> >   	unsigned int plen = 0, hlen = 0;
> > +	int coe = priv->hw->rx_csum;
> >   
> >   	/* Not first descriptor, buffer is always zero */
> >   	if (priv->sph && len)
> >   		return 0;
> >   
> >   	/* First descriptor, get split header length */
> > -	ret = stmmac_get_rx_header_len(priv, p, &hlen);
> > +	stmmac_get_rx_header_len(priv, p, &hlen);
> This function should return void if there never are any errors to
> report.


Yes, you are right. So, if we need to modify the function type , this 
patch need to be drop.

And I will send a new patch later to redefine get_rx_header_len() to 
void and delete ret there.


Please check "net: stmmac: set get_rx_header_len() as void for it didn't 
have any error code to return" later.


Thanks

Jiaxing


> >   	if (priv->sph && hlen) {
> >   		priv->xstats.rx_split_hdr_pkt_n++;
> >   		return hlen;
>
> .