Re: [DOCUMENTATION] Revised Unreliable Kernel Locking Guide

[Rusty Russell]

In message <20031215222213.GA1270@xxxxxxxxxx> you write:
> > 	How do we get rid of read locks?  Getting rid of read locks
> > 	means that writers may be changing the list underneath the readers.
> > 	That is actually quite simple:
> 
> Looks good!  Upon rereading...  Does "wmb()" want to be "smp_wmb()"?

Yes, but I didn't want to turn this into a document on memory
barriers: you'll note that I almost avoided it entirely.

> Again, upon rereading, "read Read Copy Update code" probably wants to
> be "real Read Copy Update code".   I moused it this time, given
> my past record with eyeballing.  ;-)

Fixed.

> > Now, because the 'read lock' in RCU is simply disabling preemption, a
> > caller which always preemption disabled between calling
>                       disables preemption

Ah, I inserted a 'has' as well (a caller which always has preemption
disabled...).  The implication that the caller probably has preempt
disabled as a side effect of being in an interrupt or holding a
spinlock.

> > I've uploaded a new draft with these and other fixes...
> 
> Good stuff, thank you!!!

Hey, thanks for the review!

Cheers,
Rusty.
--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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