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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [RFC/PATCH 4/4] Add support for MSI on Axon-based Cell systems
Date: Fri, 8 Jun 2007 22:16:48 +0200
To: Arnd Bergmann <arnd@arndb.de>
Cc: linuxppc-dev@ozlabs.org
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> If you do
>
> for_each_compatible_node(node, NULL, "foo") {
> 	do_something(node);
> }
>
> then the reference count is held just as long as the do_something()
> function is run,

Yeah.  so (like we discussed on irc) the of_node_get() in
the code under discussion should really be done inside the
axon_msi_setup_one() function.

> and if you do
>
> for_each_compatible_node(node, NULL, "foo")
> 	if (conditional_func(node))
> 		break;
>
> then the node variable will have the reference count.

Yes.  This is bad form though, "for_each" means for
_each_, open coding the loop would be clearer IMHO.


Segher