From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Thery Subject: Re: [PATCH] [NETNS49] support for per/namespace routing cache cleanup Date: Thu, 18 Oct 2007 09:18:48 +0200 Message-ID: <471708D8.3080808@bull.net> References: <20071017111215.GA29653@iris.sw.ru> <4715F60F.6060304@fr.ibm.com> <4716055D.4010102@sw.ru> <471610E8.8020008@fr.ibm.com> <471617CA.9090901@sw.ru> <471624C0.9020108@fr.ibm.com> <47164CBD.3040107@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <47164CBD.3040107-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Denis V. Lunev" Cc: Linux Containers , "Denis V. Lunev" , ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org List-Id: containers.vger.kernel.org Denis V. Lunev wrote: > Daniel Lezcano wrote: >> Oh, by the way, I forgot something important you spotted with the list >> protected by the mutex. >> >> When looking at ipv6/fib_hash.c with Benjamin, we need to browse the >> network namespaces list for the garbage collecting, but we are in an >> interrupt handler, so I can not use rtnl_lock. > where exactly.... Actually, it is in net/ipv6/ip6_fib.c, in fib6_clean_all(). fib6_clean_all() is called by fib6_run_gc() handler of the ip6_fib_timer. If we don't want to have one such timer per net namespace, in fib6_clean_all() we have to go through all net to clean their own fib_table_hash (using for_each_net() protected by rtnl_lock). > all interesting places are called under rtnl already... > >> Why is not possible to protect the list with a simple spinlock ? so we >> can call spin_lock_bh when we are in interrupt handler. > > see my old patch with a locking rules :) > > By the way, I have forgotten to mention, that the original patch works > from 2004 for OpenVz :) > > Regards, > Den > -- B e n j a m i n T h e r y - BULL/DT/Open Software R&D http://www.bull.com