From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ivan Khoronzhuk Subject: Re: [PATCH] net: ethernet: ti: cpsw: fix rx-usecs interrupt pacing consistency Date: Thu, 2 Jun 2016 16:30:00 +0300 Message-ID: <575034D8.4040500@linaro.org> References: <1464873292-17011-1-git-send-email-ivan.khoronzhuk@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: grygorii.strashko@ti.com, linux-omap@vger.kernel.org, netdev@vger.kernel.org To: linux-kernel@vger.kernel.org, mugunthanvnm@ti.com Return-path: In-Reply-To: <1464873292-17011-1-git-send-email-ivan.khoronzhuk@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 02.06.16 16:14, Ivan Khoronzhuk wrote: > The rx-usecs shouldn't be changed while interface down/up. > Currently, for instance, if it's set to 100us, after interface > down/up it's 500us. It's a hidden bug that can lead to lavish > interrupt pacing time increasing while "down/up" up to max value. > > Steps to reproduce: > - set rx-usecs to be 100us > - down/up interface > - read new unexpected rx-usecs > > Signed-off-by: Ivan Khoronzhuk > --- > > Based on ti-linux-4.4.y Please ignore this line, it's added by mistake. The patch is based on master. > > drivers/net/ethernet/ti/cpsw.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c > index 7b44587..9919cb3 100644 > --- a/drivers/net/ethernet/ti/cpsw.c > +++ b/drivers/net/ethernet/ti/cpsw.c > @@ -1352,7 +1352,7 @@ static int cpsw_ndo_open(struct net_device *ndev) > if (priv->coal_intvl != 0) { > struct ethtool_coalesce coal; > > - coal.rx_coalesce_usecs = (priv->coal_intvl << 4); > + coal.rx_coalesce_usecs = priv->coal_intvl; > cpsw_set_coalesce(ndev, &coal); > } > > -- Regards, Ivan Khoronzhuk