From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [PATCH net 1/2] ipv4: igmp: use alarmtimer to prevent delayed reports Date: Tue, 12 Jun 2018 18:28:18 +0200 Message-ID: <20180612162818.GA12251@lunn.ch> References: <20180611115058.GA12452@tejaswit-linux.qualcomm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, f.fainelli@gmail.com, davem@davemloft.net To: Tejaswi Tanikella Return-path: Received: from vps0.lunn.ch ([185.16.172.187]:59769 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933638AbeFLQ2V (ORCPT ); Tue, 12 Jun 2018 12:28:21 -0400 Content-Disposition: inline In-Reply-To: <20180611115058.GA12452@tejaswit-linux.qualcomm.com> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Jun 11, 2018 at 05:21:05PM +0530, Tejaswi Tanikella wrote: > On receiving a IGMPv2/v3 query, based on max_delay set in the header a > timer is started to send out a response after a random time within > max_delay. If the system then moves into suspend state, Report is > delayed until system wakes up. > > Use a alarmtimer instead of using a timer. Alarmtimer will wake the > system up from suspend to send out the IGMP report. Hi Tejaswi I think i must be missing something here. If we are suspended, we are not receiving multicast frames. If we are not receiving frames, why do we need to reply to the query? Once we resume, i expect we will reply to the next query. You could optimise restarting the flow by immediately sending a membership report, same as when the setsockopt is used to join the group. Andrew