From mboxrd@z Thu Jan 1 00:00:00 1970 From: subashab@codeaurora.org Subject: Re: [PATCH] net: rps: fix data stall after hotplug Date: Fri, 20 Mar 2015 16:40:15 -0000 Message-ID: References: <1426801839.25985.15.camel@edumazet-glaptop2.roam.corp.google.com> <1426852239.25985.33.camel@edumazet-glaptop2.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Cc: netdev@vger.kernel.org To: "Eric Dumazet" Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:53389 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750940AbbCTQkQ (ORCPT ); Fri, 20 Mar 2015 12:40:16 -0400 In-Reply-To: <1426852239.25985.33.camel@edumazet-glaptop2.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: > On Thu, 2015-03-19 at 14:50 -0700, Eric Dumazet wrote: > >> Are you seeing this race on x86 ? >> >> If IPI are not reliable on your arch, I am guessing you should fix them. >> >> Otherwise, even without hotplug you'll have hangs. > > Please try instead this patch : > > diff --git a/net/core/dev.c b/net/core/dev.c > index > 5d43e010ef870a6ab92895297fe18d6e6a03593a..baa4bff9a6fbe0d77d7921865c038060cb5efffd > 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -4320,9 +4320,8 @@ static void net_rps_action_and_irq_enable(struct > softnet_data *sd) > while (remsd) { > struct softnet_data *next = remsd->rps_ipi_next; > > - if (cpu_online(remsd->cpu)) > - smp_call_function_single_async(remsd->cpu, > - &remsd->csd); > + smp_call_function_single_async(remsd->cpu, > + &remsd->csd); > remsd = next; > } > } else > > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Thanks for the patch Eric. We are seeing this race on ARM. I will try this and update. -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project