[PATCH/RFC] PCI Error Recovery

[Linas Vepstas]

On Mon, Mar 14, 2005 at 09:33:03PM +0900, Hidetoshi Seto was heard to remark:
> Linas Vepstas wrote:
> >+enum pci_device_io_state {
>
> ... but I think it's of value to have the list of states.
> (Even it seems that the list what originally you want isn't "state list"
>  but "event list".)

Sorry, you are right, I confused the concept of "state transition" with 
the concept of "state", I will try to clarify the difference in the next
patch.

> would be realized by:
>  event(STATE_CHANGED,ISOLATED) + event(TRY_RECOVER,*data)
>  event(STATE_CHANGED,NORMAL)
>  event(STATE_CHANGED,DEAD)
> I think the latter style is more generic.

Hmm, are you suggesting that there **shouldn't** be a callback 
function in struct pci_driver, and that instead, all state changes
should be delivered as events? (i.e. by means of the notifier_chain
mechanism?) Hmm ... thats possible, I'd have to rearrange the code a
bit.

Is there a long-term philosphy for the Linux kernel on a question like
this?  That is, when should changes add callbacks to structures, 
as opposed to notifier-chain based events?  The callback is a bit
simpler, and maybe a tiny bit faster, but its less flexible in the 
long run (e.g. anyone can listen for the events, but only device 
drivers can get callbacks). Comments, please?

--linas