On Wednesday, March 2, 2005 3:30 pm, Linas Vepstas wrote: > Put it another way: a device driver author should have the opportunity > to poll the pci bus status if they so desire. Polling for bus status > on ppc64 is real easy. Given what Jesse Barnes was saying, it sounded > like a simple (optional, the dev driver doesn't have to use it) poll > is not enough, because some errors might be transactional.
Yeah, I'm not arguing against your call, it could be useful for polling for errors or for use in an error handling callback. What I was trying to say earlier (maybe I wasn't very clear) was that the idea of creating transactions for certain types of I/O (even if those transactions are artificial and purely in software) can be useful since it creates boundaries and context, making it easier to figure out what went wrong, hopefully making it easier to fix things and carry on. IOW, using Seto-san's iochk_clear/iochk_read interface makes certain types of errors much easier to deal with since you *know* where an error occurred and can presumably deal with it right away. The problem comes in for things that aren't well encapsulated, like DMA, for which error polling or some sort of callback is needed (and even with polling you'll need to poll in an error handling thread as you mentioned since the driver may start DMA, return, and the error can happen later when we're not actually in driver code). So I think we mostly agree on what things need to be done, you and benh just have to fight it out over the details. :) Jesse - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
