From mboxrd@z Thu Jan  1 00:00:00 1970
From: jamal <hadi@cyberus.ca>
Subject: Re: [PATCH 2.6] generic network statistics (was Re: [6/6]: jenkins
	hash for neigh / Statistics)
Date: 28 Sep 2004 22:22:07 -0400
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Cc: Harald Welte <laforge@gnumonks.org>,
        Robert Olsson <Robert.Olsson@data.slu.se>,
        Stephen Hemminger <shemminger@osdl.org>,
        "David S. Miller" <davem@davemloft.net>, herbert@gondor.apana.org.au,
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To: Thomas Graf <tgraf@suug.ch>
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On Tue, 2004-09-28 at 09:33, Thomas Graf wrote:
> > Speaking of generic stats; i have a patch netlink ready which may need
> > some extensions. I did post it  a while back on netdev but didnt get
> > feedback.
> 
> The code looks good and I couldn't spot any errors but I'm not
> sure if the locking in gen_copy_[x]stats is a good thing.
> Shouldn't that be done earlier by the caller? 

In the netsched code that became a portability issue; Dave fixed it
there, so i just replicated here. If you feel like doing something
clever you are welcome to submit a patch.

> This prevents
> corruption but it allows duplicated TLVs in an skb. I suggest
> to make the caller have a lock on his data and only allow one
> dumper at the same time until the dump is complete, or at least
> provide a lockless variant for callers doing the locking on
> their own.
> 

Reminds me:
gnet_stats needs to have TLVs embedded in it.
bytes,drops, packets are generic enough; others are not.
So if we add a length field then we can add TLVs for things like
QSTATS = { qlen, backlog}  etc.
This means we could then allow for adding a lot of different
stats. A big lesson from current tc_stats.

cheers,
jamal