Hello, Adam. On Tue, Oct 04, 2016 at 08:49:18AM -0700, Adam Manzanares wrote: > > I wonder whether the right thing to do is adding bio->bi_ioprio which > > is initialized on bio submission and carried through req->ioprio. > > I looked around and thought about this and I'm not sure if this will help. > I dug into the bio submission code and I thought generic_make_request was > the best place to save the ioprio information. This is quite close in > the call stack to init_request_from bio. Bcache sets the bio priority before > the submission, so we would have to check to see if the bio priority was > valid on bio submission leaving us with the same problem. Leaving the > priority in the upper bits of bio->bi_rw is fine with me. It may help to > have the bio->bi_ioprio for clarity, but I think we will still face the > issue of having to check if this value is set when we submit the bio or > init the request so I'm leaning towards leaving it as is. I see. Thanks for looking into it. It's icky that we don't have a clear path of propagating ioprio but let's save that for another day. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html