netdev - Re: [PATCH ipvs-next] ipvs: Remove rcu_read_unlock();rcu_read

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20130426005900.GA4303@localhost>
Date:	Fri, 26 Apr 2013 02:59:26 +0200
From:	Pablo Neira Ayuso <pablo@...filter.org>
To:	Julian Anastasov <ja@....bg>
Cc:	Simon Horman <horms@...ge.net.au>, lvs-devel@...r.kernel.org,
	netdev@...r.kernel.org, netfilter-devel@...r.kernel.org,
	Wensong Zhang <wensong@...ux-vs.org>
Subject: Re: [PATCH ipvs-next] ipvs: Remove rcu_read_unlock();rcu_read_lock();

Hi Julian,

On Thu, Apr 25, 2013 at 11:15:25AM +0300, Julian Anastasov wrote:
> 
> 	Hello,
> 
> On Thu, 25 Apr 2013, Simon Horman wrote:
> 
> > It is unclear to me that there is any utility in the following:
> > 
> > 	 rcu_read_unlock();
> > 	 rcu_read_lock();
> 
> 	I thought it is a good idea for fixed hash table
> of IP_VS_TAB_BITS=20. May be if guarded by
> 
> 	if (!((++idx) & 4095))
> 
> to reduce its rate to 256 (with idx++ removed from the for loop) ?
> 
> 	Netfilter has no such logic for nf_conntrack because
> it has limit of 16384 rows.

We seem to be supporting over that limit via module_param and sysfs:

/sys/module/nf_conntrack/parameters/hashsize

Regards.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html