Subject: Re: [PATCH v3 10/12] l2tp: Add L2TP ethernet pseudowire support

From: James Chapman <[email-masked]>
Date: Wed, 31 Mar 2010 10:35:29 +0100

Stephen Hemminger wrote:
> On Tue, 30 Mar 2010 17:18:19 +0100
> James Chapman <[email-masked]> wrote:
> 
>> +struct l2tp_eth_net {
>> +	struct list_head l2tp_eth_dev_list;
>> +	rwlock_t l2tp_eth_lock;
>> +};
> 
> Reader/write locks are discouraged because they are slower than
> spin locks.  If you have lots of readers use RCU, if reading
> is infrequent just use a spin lock.

Ok. In doing the conversion of the rwlocks in l2tp_core.c, I'm finding
that some list access primitives don't have rcu equivalents, namely
list_is_last(), list_for_each_entry_safe(). Is this intentional? Should
I add the missing ones in a separate patch?

-- 
James Chapman
Katalix Systems Ltd
http://www.katalix.com
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