Re: [PATCH] [0/11] SYSCTL: Use RCU to avoid races with stringsysctls

[Andi Kleen]

> So we have sysctl have locking problems, not new sysctl regressions.

Ok.

> > If the strings were made a bit smaller this could be also 
> > put on the stack, but I didn't dare for 256 bytes. 
> 
> Hmm.  rcu wise that sounds wrong, but I haven't looked into your

What sounds wrong? 

The reason for the copies is that when the reader sleeps 
rcu_read_lock() cannot be used to protect the string completely,
so it copies instead.

The alternative would have been to use SRCU, but I didn't like that.

> cool new data structure yet.

It's not really particularly new or cool, it's just a simple RCU wrapper
around a string.

-Andi

-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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