From: David Miller <davem@davemloft.net>
To: patrick.ohly@intel.com
Cc: nanog@85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org,
netdev@vger.kernel.org, opurdila@ixiacom.com
Subject: Re: Storing hardware timestamps - how about using the new skb's control block?
Date: Wed, 12 Nov 2008 00:39:27 -0800 (PST) [thread overview]
Message-ID: <20081112.003927.153710640.davem@davemloft.net> (raw)
In-Reply-To: <1226478438.31699.55.camel@ecld0pohly>
From: Patrick Ohly <patrick.ohly@intel.com>
Date: Wed, 12 Nov 2008 09:27:18 +0100
> My understanding of sk_buff->cb might be wrong, but isn't each layer
> allowed to overwrite it as the packet traverses the different queues?
Right.
> skb_share_check() is not mandatory:
And besides, skb_share_check() doesn't check if somebody "owns" the
skb->cb[]
And if you bump the reference count or something silly like that to
get skb_share_check() to copy the packet, every single locally
destined TCP packet will be copied. That will effectively kill
performance.
prev parent reply other threads:[~2008-11-12 8:39 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-11 20:53 Storing hardware timestamps - how about using the new skb's control block? Mark Smith
2008-11-12 8:27 ` Patrick Ohly
2008-11-12 8:39 ` David Miller [this message]
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