From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from vps0.lunn.ch (vps0.lunn.ch [156.67.10.101]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2453219E827; Tue, 10 Sep 2024 15:58:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=156.67.10.101 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725983920; cv=none; b=LIuDxPZCSg8VvpPuwjLZ9LNy2m4gv+DgLrYLolhLgl8LQVmQcMqm5EYWG9TDdhn/708Ug/J/RU78nkb2syVXjoHBa2sqaBOGn8L9ftLXeY3byTwfoE/2yOSxAIjuEYXIVRn/ZTbCO61Cdj+4FCb5uVF4yr6k4s1u7pZiND/2GkE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725983920; c=relaxed/simple; bh=JLJaCOiABB/oP/JYn7vUsmEd/L1StlhDnijFrQJ2s7c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=YuVQTGWxh6SQQtE6053apULsX8Zo/eccKTjZPszZB4vm9aydHYUNL/oYrmtgAOzpy+L9idPpW+8KUPRA+k0YyslY10Woaz9b25AgqrZ6E//LZbSQUohGjVxvLw9Tdi0WVIiDECsHV/AYwmAnotj0Wmaesh3Mw/q6sVl790uYYnM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch; spf=pass smtp.mailfrom=lunn.ch; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b=Vu69pIpw; arc=none smtp.client-ip=156.67.10.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lunn.ch Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="Vu69pIpw" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=QDxDa9XCwWgMAD9MF1Dm8QsW5pDstiAmlvOyC9GXuKU=; b=Vu69pIpwOJbG/4sxBpf8rxtsMU EZ7eu/YM/PHyBUOGEtkI3nGgGrzP7Q2ET9GLiuRPP5Q+Cs+ueavD0Ii0LjXQMvJg19r5nv59PuAtE oi/N7lybsEMC22fitMpxgZ1boY/LAG2QOTgEYqt/brs5oIBLPG+3vhSPXSoH/quDfho4=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1so3G2-0077k0-O0; Tue, 10 Sep 2024 17:58:22 +0200 Date: Tue, 10 Sep 2024 17:58:22 +0200 From: Andrew Lunn To: Qianqiang Liu Cc: chris.snook@gmail.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Oleksij Rempel Subject: Re: [PATCH] net: ag71xx: remove dead code path Message-ID: <196dc563-85ec-491d-8e2e-8749f3b07ff4@lunn.ch> References: <20240910152254.21238-1-qianqiang.liu@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240910152254.21238-1-qianqiang.liu@163.com> On Tue, Sep 10, 2024 at 11:22:54PM +0800, Qianqiang Liu wrote: > The 'err' is always zero, so the following branch can never be executed: > if (err) { > ndev->stats.rx_dropped++; > kfree_skb(skb); > } > Therefore, the 'if' statement can be removed. This code was added by Oleksij Rempel . It is good to Cc: him, he might have useful comments. Your changed does look correct, but maybe ret was actually supposed to be set somewhere? Is there an actual bug hiding here somewhere? Andrew > > Signed-off-by: Qianqiang Liu > --- > drivers/net/ethernet/atheros/ag71xx.c | 12 +++--------- > 1 file changed, 3 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/ethernet/atheros/ag71xx.c b/drivers/net/ethernet/atheros/ag71xx.c > index 96a6189cc31e..5477f3f87e10 100644 > --- a/drivers/net/ethernet/atheros/ag71xx.c > +++ b/drivers/net/ethernet/atheros/ag71xx.c > @@ -1616,7 +1616,6 @@ static int ag71xx_rx_packets(struct ag71xx *ag, int limit) > unsigned int i = ring->curr & ring_mask; > struct ag71xx_desc *desc = ag71xx_ring_desc(ring, i); > int pktlen; > - int err = 0; > > if (ag71xx_desc_empty(desc)) > break; > @@ -1646,14 +1645,9 @@ static int ag71xx_rx_packets(struct ag71xx *ag, int limit) > skb_reserve(skb, offset); > skb_put(skb, pktlen); > > - if (err) { > - ndev->stats.rx_dropped++; > - kfree_skb(skb); > - } else { > - skb->dev = ndev; > - skb->ip_summed = CHECKSUM_NONE; > - list_add_tail(&skb->list, &rx_list); > - } > + skb->dev = ndev; > + skb->ip_summed = CHECKSUM_NONE; > + list_add_tail(&skb->list, &rx_list); > > next: > ring->buf[i].rx.rx_buf = NULL; > -- > 2.39.2 > >