From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin LaHaise Subject: Re: [PATCH v4 3/3] net: igmp: Allow user-space configuration of igmp unsolicited report interval Date: Wed, 7 Aug 2013 09:43:41 -0400 Message-ID: <20130807134341.GM8043@kvack.org> References: <20130731063442.GA10498@order.stressinduktion.org> <1375812195-6575-1-git-send-email-william.manley@youview.com> <1375812195-6575-4-git-send-email-william.manley@youview.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, luky-37@hotmail.com, sergei.shtylyov@cogentembedded.com, bhutchings@solarflare.com, davem@davemloft.net, hannes@stressinduktion.org To: William Manley Return-path: Received: from kanga.kvack.org ([205.233.56.17]:36123 "EHLO kanga.kvack.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933187Ab3HGNnm (ORCPT ); Wed, 7 Aug 2013 09:43:42 -0400 Content-Disposition: inline In-Reply-To: <1375812195-6575-4-git-send-email-william.manley@youview.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Aug 06, 2013 at 07:03:15PM +0100, William Manley wrote: > Adds the new procfs knobs: > > /proc/sys/net/ipv4/conf/*/igmpv2_unsolicited_report_interval > /proc/sys/net/ipv4/conf/*/igmpv3_unsolicited_report_interval > > Which will allow userspace configuration of the IGMP unsolicited report > interval (see below) in milliseconds. The defaults are 10000ms for IGMPv2 > and 1000ms for IGMPv3 in accordance with RFC2236 and RFC3376. > > Background: > > If an IGMP join packet is lost you will not receive data sent to the > multicast group so if no data arrives from that multicast group in a > period of time after the IGMP join a second IGMP join will be sent. The > delay between joins is the "IGMP Unsolicited Report Interval". > > Prior to this patch this value was hard coded in the kernel to 10s for > IGMPv2 and 1s for IGMPv3. 10s is unsuitable for some use-cases, such as > IPTV as it can cause channel change to be slow in the presence of packet > loss. > > This patch allows the value to be overridden from userspace for both > IGMPv2 and IGMPv3 such that it can be tuned accoding to the network. > > Tested with Wireshark and a simple program to join a (non-existent) > multicast group. The distribution of timings for the second join differ > based upon setting the procfs knobs. > > igmpvX_unsolicited_report_interval is intended to follow the pattern > established by force_igmp_version, and while a procfs entry has been added > a corresponding sysctl knob has not as it is my understanding that sysctl > is deprecated[1]. > > [1]: http://lwn.net/Articles/247243/ > > Signed-off-by: William Manley Acked-by: Benjamin LaHaise Also good. Thanks! -ben > --- > include/linux/inetdevice.h | 2 ++ > net/ipv4/devinet.c | 8 ++++++++ > net/ipv4/igmp.c | 19 +++++++++++++++++-- > 3 files changed, 27 insertions(+), 2 deletions(-) > > diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h > index d4c56fc..43b3c72 100644 > --- a/include/linux/inetdevice.h > +++ b/include/linux/inetdevice.h > @@ -28,6 +28,8 @@ enum > IPV4_DEVCONF_ARPFILTER, > IPV4_DEVCONF_MEDIUM_ID, > IPV4_DEVCONF_FORCE_IGMP_VERSION, > + IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL, > + IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL, > IPV4_DEVCONF_NOXFRM, > IPV4_DEVCONF_NOPOLICY, > IPV4_DEVCONF_ARP_ANNOUNCE, > diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c > index a9561c4..56ecb1b 100644 > --- a/net/ipv4/devinet.c > +++ b/net/ipv4/devinet.c > @@ -73,6 +73,8 @@ static struct ipv4_devconf ipv4_devconf = { > [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, > [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, > [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, > + [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/, > + [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/, > }, > }; > > @@ -83,6 +85,8 @@ static struct ipv4_devconf ipv4_devconf_dflt = { > [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, > [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, > [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1, > + [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/, > + [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/, > }, > }; > > @@ -2096,6 +2100,10 @@ static struct devinet_sysctl_table { > DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"), > DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION, > "force_igmp_version"), > + DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL, > + "igmpv2_unsolicited_report_interval"), > + DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL, > + "igmpv3_unsolicited_report_interval"), > > DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"), > DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"), > diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c > index 9f0aaea..c5541da 100644 > --- a/net/ipv4/igmp.c > +++ b/net/ipv4/igmp.c > @@ -141,10 +141,25 @@ > > static int unsolicited_report_interval(struct in_device *in_dev) > { > + int interval_ms, interval_jiffies; > + > if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) > - return IGMP_V2_Unsolicited_Report_Interval; > + interval_ms = IN_DEV_CONF_GET( > + in_dev, > + IGMPV2_UNSOLICITED_REPORT_INTERVAL); > else /* v3 */ > - return IGMP_V3_Unsolicited_Report_Interval; > + interval_ms = IN_DEV_CONF_GET( > + in_dev, > + IGMPV3_UNSOLICITED_REPORT_INTERVAL); > + > + interval_jiffies = msecs_to_jiffies(interval_ms); > + > + /* _timer functions can't handle a delay of 0 jiffies so ensure > + * we always return a positive value. > + */ > + if (interval_jiffies <= 0) > + interval_jiffies = 1; > + return interval_jiffies; > } > > static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im); > -- > 1.7.10.4 -- "Thought is the essence of where you are now."