From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 0/7] XDP redirect tracepoints
Date: Tue, 29 Aug 2017 10:51:43 -0700 (PDT)
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From: Jesper Dangaard Brouer <brouer@redhat.com>
Date: Tue, 29 Aug 2017 16:37:35 +0200

> I feel this is as far as I can take the tracepoint infrastructure to
> assist XDP monitoring.
> 
> Tracepoints comes with a base overhead of 25 nanosec for an attached
> bpf_prog, and 48 nanosec for using a full perf record. This is
> problematic for the XDP use-case, but it is very convenient to use the
> existing perf infrastructure.
> 
>>>From a performance perspective, the real solution would be to attach
> another bpf_prog (that understand xdp_buff), but I'm not sure we want
> to introduce yet another bpf attach API for this.
> 
> One thing left is to standardize the possible err return codes, to a
> limited set, to allow easier (and faster) mapping into a bpf map.

Series applied, thanks Jesper.