Re: [Ocf-linux-users] OCF CBIMM=1 in SMP breaks

[David M. <Dav...@se...>]

Jivin Kabir Ahsan lays it down ...
> Hi David
> Sorry for writing directly. I tried using the openswan/ocf mailing list
> but I guess my posting is not showing up.
> Any how, I wanted to let you know that when I run OCF-based IPsec with
> CBIMM=1 in SMP mode for kernel 2.6.23 then I run spinlock recursion
> issue in the ipsec_rsm routine. This problem could be easily manifested
> using the OCF-null driver. 
> Is this a known bug? If yes, is there any recent patch to fix the
> problem?

That makes sense I guess,  as CBIMM means we call back into ipsec
before the call to do the request returns.  Makes the coding much
trickier to get right.

On an SMP kernel I would disable CBIMM in fact I would almost
always do that,  but I know that small low- cache systems can go
quite a bit faster using CBIMM,  so it stays.

If anyone want to suggest fixes for these it would be appreciated :-)
Otherwise I will try and review the locking when I get some time and
see if we can reduce the locking windows and cleanup CBIMM,

Cheers,
Davidm


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David McCullough,  dav...@se...,   Ph:+61 734352815
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