From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1035168AbdAIRZl (ORCPT ); Mon, 9 Jan 2017 12:25:41 -0500 Received: from lelnx194.ext.ti.com ([198.47.27.80]:44911 "EHLO lelnx194.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1035128AbdAIRZk (ORCPT ); Mon, 9 Jan 2017 12:25:40 -0500 Subject: Re: [PATCH 3/4] net: ethernet: ti: cpsw: don't duplicate ndev_running To: Ivan Khoronzhuk , , References: <1483893663-15673-1-git-send-email-ivan.khoronzhuk@linaro.org> <1483893663-15673-4-git-send-email-ivan.khoronzhuk@linaro.org> CC: , From: Grygorii Strashko Message-ID: Date: Mon, 9 Jan 2017 11:25:38 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <1483893663-15673-4-git-send-email-ivan.khoronzhuk@linaro.org> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [128.247.83.96] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/08/2017 10:41 AM, Ivan Khoronzhuk wrote: > No need to create additional vars to identify if interface is running. > So simplify code by removing redundant var and checking usage counter > instead. > > Signed-off-by: Ivan Khoronzhuk > --- > drivers/net/ethernet/ti/cpsw.c | 14 ++++---------- > 1 file changed, 4 insertions(+), 10 deletions(-) > > diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c > index 40d7fc9..daae87f 100644 > --- a/drivers/net/ethernet/ti/cpsw.c > +++ b/drivers/net/ethernet/ti/cpsw.c > @@ -357,7 +357,6 @@ struct cpsw_slave { > struct phy_device *phy; > struct net_device *ndev; > u32 port_vlan; > - u32 open_stat; > }; > > static inline u32 slave_read(struct cpsw_slave *slave, u32 offset) > @@ -1241,7 +1240,7 @@ static int cpsw_common_res_usage_state(struct cpsw_common *cpsw) > u32 usage_count = 0; > > for (i = 0; i < cpsw->data.slaves; i++) > - if (cpsw->slaves[i].open_stat) > + if (netif_running(cpsw->slaves[i].ndev)) > usage_count++; Not sure this will work as you expected, but may be I've missed smth :( code in static int __dev_open(struct net_device *dev) .. set_bit(__LINK_STATE_START, &dev->state); if (ops->ndo_validate_addr) ret = ops->ndo_validate_addr(dev); if (!ret && ops->ndo_open) ret = ops->ndo_open(dev); netpoll_poll_enable(dev); if (ret) clear_bit(__LINK_STATE_START, &dev->state); .. so, netif_running(ndev) will start returning true before calling ops->ndo_open(dev); > > return usage_count; > @@ -1502,7 +1501,7 @@ static int cpsw_ndo_open(struct net_device *ndev) > CPSW_RTL_VERSION(reg)); > > /* initialize host and slave ports */ > - if (!cpsw_common_res_usage_state(cpsw)) > + if (cpsw_common_res_usage_state(cpsw) < 2) Ah. You've changed the condition here. I think it might be reasonable to hide this inside cpsw_common_res_usage_state() and seems it can be renamed to smth like cpsw_is_running(). > cpsw_init_host_port(priv); > for_each_slave(priv, cpsw_slave_open, priv); > > @@ -1513,7 +1512,7 @@ static int cpsw_ndo_open(struct net_device *ndev) > cpsw_ale_add_vlan(cpsw->ale, cpsw->data.default_vlan, > ALE_ALL_PORTS, ALE_ALL_PORTS, 0, 0); > > - if (!cpsw_common_res_usage_state(cpsw)) { > + if (cpsw_common_res_usage_state(cpsw) < 2) { > /* disable priority elevation */ > __raw_writel(0, &cpsw->regs->ptype); > > @@ -1556,9 +1555,6 @@ static int cpsw_ndo_open(struct net_device *ndev) > cpdma_ctlr_start(cpsw->dma); > cpsw_intr_enable(cpsw); > > - if (cpsw->data.dual_emac) > - cpsw->slaves[priv->emac_port].open_stat = true; > - > return 0; > > err_cleanup: > @@ -1578,7 +1574,7 @@ static int cpsw_ndo_stop(struct net_device *ndev) > netif_tx_stop_all_queues(priv->ndev); > netif_carrier_off(priv->ndev); > > - if (cpsw_common_res_usage_state(cpsw) <= 1) { > + if (!cpsw_common_res_usage_state(cpsw)) { and here __LINK_STATE_START will be cleared before calling ops->ndo_stop(dev); So, from one side netif_running(ndev) usage will simplify cpsw_common_res_usage_state() internals, but from another side - it will make places where it's used even more entangled :( as for me, because when cpsw_common_res_usage_state() will return 1 in cpsw_ndo_open() it will mean "no interfaces is really running yet", but the same value 1 in cpsw_ndo_stop() will mean "there are still one is running". > napi_disable(&cpsw->napi_rx); > napi_disable(&cpsw->napi_tx); > cpts_unregister(cpsw->cpts); > @@ -1592,8 +1588,6 @@ static int cpsw_ndo_stop(struct net_device *ndev) > cpsw_split_res(ndev); > > pm_runtime_put_sync(cpsw->dev); > - if (cpsw->data.dual_emac) > - cpsw->slaves[priv->emac_port].open_stat = false; > return 0; > } > > -- regards, -grygorii