Messages in this thread | | | From | Rusty Russell <> | Subject | Re: request->ioprio | Date | Thu, 7 Aug 2008 06:33:05 +1000 |
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On Wednesday 06 August 2008 19:16:36 Fernando Luis Vázquez Cao wrote: > Hi Jens, Rusty,
Hi Fernando,
> Trying to implement i/o tracking all the way up to the page cache (so > that cfq and the future cgroup-based I/O controllers can schedule > buffered I/O properly) I noticed that struct request's ioprio is > initialized but never used for I/O scheduling purposes. Indeed there > seems to be one single user of this member: virtio_blk.
Hey, do I win a prize? :)
> Virtio uses > struct request's ioprio in the request() function of the virtio block > driver, which just copies the ioprio value to the output header of > virtblk_req.
Yes, we pass it through to the host, in the assumption they might want to use it to schedule our I/Os relative to each other.
I'm a little surprised noone else uses it, but I'm sure they will... Rusty. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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