From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 477E0DDDF4 for ; Tue, 13 Nov 2007 09:33:01 +1100 (EST) Subject: Re: [PATCH] sungem: fix suspend regression due to NAPI changes From: Benjamin Herrenschmidt To: Johannes Berg In-Reply-To: <1194889547.4456.4.camel@johannes.berg> References: <1194889547.4456.4.camel@johannes.berg> Content-Type: text/plain Date: Tue, 13 Nov 2007 09:32:46 +1100 Message-Id: <1194906766.18185.79.camel@pasglop> Mime-Version: 1.0 Cc: netdev , Stephen Hemminger , "David S. Miller" , linuxppc-dev list Reply-To: benh@kernel.crashing.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2007-11-12 at 18:45 +0100, Johannes Berg wrote: > Commit bea3348e (the NAPI changes) made sungem unconditionally enable > NAPI when resuming and unconditionally disable when suspending, this, > however, makes napi_disable() hang when suspending when the interface > was taken down before suspend because taking the interface down also > disables NAPI. This patch makes touching the napi struct in > suspend/resume code paths depend on having the interface up, thereby > fixing the hang on suspend. > > The patch also moves the napi_disable() in gem_close() under the lock so > that the NAPI state is always modified atomically together with the > "opened" variable. > > Signed-off-by: Johannes Berg Thanks for fixing that ! Acked-by: Benjamin Herrenschmidt --- > --- > drivers/net/sungem.c | 11 +++++------ > 1 file changed, 5 insertions(+), 6 deletions(-) > > --- everything.orig/drivers/net/sungem.c 2007-11-12 18:22:49.948748047 +0100 > +++ everything/drivers/net/sungem.c 2007-11-12 18:24:30.708748481 +0100 > @@ -2333,10 +2333,10 @@ static int gem_close(struct net_device * > { > struct gem *gp = dev->priv; > > - napi_disable(&gp->napi); > - > mutex_lock(&gp->pm_mutex); > > + napi_disable(&gp->napi); > + > gp->opened = 0; > if (!gp->asleep) > gem_do_stop(dev, 0); > @@ -2355,8 +2355,6 @@ static int gem_suspend(struct pci_dev *p > > mutex_lock(&gp->pm_mutex); > > - napi_disable(&gp->napi); > - > printk(KERN_INFO "%s: suspending, WakeOnLan %s\n", > dev->name, > (gp->wake_on_lan && gp->opened) ? "enabled" : "disabled"); > @@ -2370,6 +2368,8 @@ static int gem_suspend(struct pci_dev *p > > /* If the driver is opened, we stop the MAC */ > if (gp->opened) { > + napi_disable(&gp->napi); > + > /* Stop traffic, mark us closed */ > netif_device_detach(dev); > > @@ -2460,6 +2460,7 @@ static int gem_resume(struct pci_dev *pd > /* Re-attach net device */ > netif_device_attach(dev); > > + napi_enable(&gp->napi); > } > > spin_lock_irqsave(&gp->lock, flags); > @@ -2479,8 +2480,6 @@ static int gem_resume(struct pci_dev *pd > spin_unlock(&gp->tx_lock); > spin_unlock_irqrestore(&gp->lock, flags); > > - napi_enable(&gp->napi); > - > mutex_unlock(&gp->pm_mutex); > > return 0; >