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SubjectRe: Allocation of sk_buffs in the kernel
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> > I'm currently writing a kernel patch where it is essential to get
known>
> > when a sk_buff is allocated. Or better said I have to get known when a
> > sk_buff is effectively a new packet in the kernel-
>I don't want to guess why you need that...
I'm currently writing a stack profiler as my diploma thesis. It should give
a statistic how long a packet takes from one part of the network stack to
the other. So I have to watch the sk_buffs travelling through the kernel
and I need badly to know when they are allocated :) And, on top, the
deadline is in one week, and there are really strange things going on ;)

> > I currently identified 3 functions in the kernel where sk_buffs are
> > allocated: alloc_skb (of course), skb_linearize and pskb_expand_head.
Or at
> > least there new data is defined for the sk_buffs.
> >
> > Now I monitor a TCP session, a FTP download better said, and on the
> > interface arrives around 30000 packets for 50 MB of data. But in my
kernel
> > patch only 2000 packets are allocated, or at least I see only the
> > allocation of 2000 packets.
> >
> > Can anyone help me where I can find my missing packets? ;)) I need them
> > badly! *GG*

> There should be no skbuff allocation outside net/core/skbuff.c and all
> normal[1] networking drivers also don't use private pools. Perhaps
> you forgot to instrument a case there.
I have done some bit more testing yesterday, and the problem occurs in
either sending and receiving way, on two different ethernet drivers
(eepro100 and

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