On Wed, 12 Dec 2007 15:38:15 -0500 (EST), Kiyoshi Ueda <k-ueda@xxxxxxxxxxxxx> wrote: > On Tue, 11 Dec 2007 15:48:03 -0800, Pete Zaitcev <zaitcev@xxxxxxxxxx> wrote: > > > - end_that_request_first(rq, uptodate, rq->hard_nr_sectors); > > > - end_that_request_last(rq, uptodate); > > > + if (__blk_end_request(rq, error, blk_rq_bytes(rq))) > > > + BUG(); > > My understanding was, blk_end_request() is the same thing, only > > takes the queue lock. But then, should I refactor ub so that it > > calls __blk_end_request if request function ends with an error > > and blk_end_request if the end-of-IO even is processed? > I'm using __blk_end_request() here and I think it's sufficient, because: > o end_that_request_last() must be called with the queue lock held > o ub_end_rq() calls end_that_request_last() without taking > the queue lock in itself. > So the queue lock must have been taken outside ub_end_rq(). > But, if ub is calling end_that_request_last() without the queue lock, > it is a bug in the original code and we should use blk_end_request() > to fix that. So, I have to rewrite ub to split the paths after all, right? Let's do this then: I'll wait until your patch gets to Linus and then update it with the split. The reason is, I need the whole enchilada applied and I don't want to bother tracking iterations and all the little segments (of which you already have 30). Until then, ub will have a race by using your original small patch. Best wishes, -- Pete - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
