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From: Dmitri Denissov <ddenissov@sandvine.com>
To: 'Julian Elischer' <julian@elischer.org>, freebsd-net@freebsd.org
Date: Fri, 21 May 2004 01:26:52 -0400
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Subject: RE: protecting netgraph calls from outside of the network context
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On Thu, 20 May 2004, Julian Elischer wrote:

> > This is kind of a bridge, connected to ng_ether interface nodes.
> > Sometimes it queues received packets and later /on a timer 
> call or a call
> > from the user space/
> > it re-injects the packets using ng_send_data.
> > 
> 
> reinjects it to where?
> 

To the adjacent ng_ether node connected via the lower hook. 
So the question is how to protect the ng_send_data() call originated 
from timer or user space context.
> 
> > 
> > > From: Julian Elischer [mailto:julian@elischer.org]
> > > Sent: Thursday, May 20, 2004 5:34 PM
> > > 
> > > 
> > > Ha! funny you should ask that exactly now..
> > > I was just discussing this with Robert Watson..
> > > 
> > > The answer is  "it depends on what you want to do".
> > > 
> > > What DO you want to do and what does your node do?
> > > netgraph has internal locking in 5.x that you need to 
> > > interact with but it should be pretty transparrent 
> > > depending on what you are doing..
> > > 
> > > 
> > > On Thu, 20 May 2004, Dmitri Denissov wrote:
> > > 
> > > > Hi,
> > > > 
> > > > Currently netgraph code uses splnet/splx to protect 
> timeout calls.
> > > > This doesn't work with 5.2 SMP kernel. What is the 
> proper method 
> > > > here for a custom netgraph node? Is the Giant lock only the way?
> > > > 
> > > > Thanks
> > > > 
> > > > --
> > > > Dmitri
> > 
>