Re: RCU (or equivalent) for NetBSD?

["J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>]

On Mar 3, 2013, at 12:18 PM, Dennis Ferguson 
<dennis.c.ferguson%gmail.com@localhost> wrote:

> 
> On 3 Mar, 2013, at 14:37 , Thor Lancelot Simon <tls%panix.com@localhost> 
> wrote:
> 
>> On Sun, Mar 03, 2013 at 12:53:01PM +0800, Dennis Ferguson wrote:
>>> 
>>> Could the NetBSD kernel now acquire RCU, or RCU-like,
>>> infrastructure?  I suspect I am incapable of designing this
>>> myself but I have a pretty good idea about what it would
>>> usefully enable.
>> 
>> The documentation is poor, but it references a paper which explains
>> better -- does pserialize(9) do what you want?
> 
> The basic functions seem to be a perfect fit.
> 
> The only bit I'm confused about is what the implication of
> 
>    The read operations may happen from software interrupt at the
>    IPL_SOFTCLOCK symbolic level.
> 
> is for an application that wants to use this interface.  Processing of packets
> arriving from hardware interfaces is traditionally run at IPL_SOFTNET, is the
> above telling me a reader can't use pserialize(9) if it is running at that
> level?

The opposite: pserialize may be used from soft interrupt context.

--
J. Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig 
(Germany)