Re: [PATCH net-next 0/7] Allow to monitor multicast cache event via rtnetlink

[Nicolas Dichtel <nicolas.dichtel@6wind.com>]

Le 04/12/2012 21:02, Nicolas Dichtel a écrit :
> Le 04/12/2012 19:09, David Miller a écrit :
>> From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
>> Date: Tue,  4 Dec 2012 12:13:34 +0100
>>
>>> The goal of this serie is to be able to monitor multicast activities via
>>> rtnetlink.
>>>
>>> The main changes are:
>>>   - when user dumps mfc entries it now get all entries, included the unresolved
>>>     cache.
>>>   - kernel sends rtnetlink when it adds/deletes mfc entries.
>>>
>>> As usual, the patch against iproute2 will be sent once the patches are
>>> included and
>>> net-next merged. I can send it on demand.
>>
>> This looks good, applied, thanks Nicolas.
>>
>> The one thing I worry about are those 64-bit statistics.  I fear that they
>> not be 64-bit aligned in the final netlink message.  This matters on cpus
>> that trap on unaligned loads/stores, such as sparc and MIPS.
>>
>> Can you validate this?
>>
> I can have a try on a tile platform. I don't have access to sparc or mips.
Hmm, I've read arm instead of mips! So I've tried on mips. Data are aligned on 
32-bit, like for all netlink messages. nla_put_u64() will do the same, as it 
calls nla_put().

And the kernel will only use memcpy() to treat this attribute. Reader will be in 
userland.