On Mon, May 10, 2021 at 9:39 PM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > On Tue, May 11, 2021 at 10:13:41AM +0800, Guoqing Jiang wrote: > > > > Song and Artur, what are your opinion? > > > In the initial version of the io accounting patch the bio was cloned instead > > > of just overriding bi_end_io and bi_private. Would this be the right approach? > > > > > > https://lore.kernel.org/linux-raid/20200601161256.27718-1-artur.paszkiewicz@xxxxxxxxx/ > > > > Maybe we can have different approach for different personality layers. > > > > 1. raid1 and raid10 can do the accounting in their own layer since they > > already > > ?????? clone bio here. > > 2. make the initial version handles other personality such as raid0 and > > raid5 > > ?????? in the md layer. > > > > Also a sysfs node which can enable/disable the accounting could be helpful. > > Yes. Also if the original bi_end_io is restore before completing the > bio you can still override it. Do you mean we can somehow avoid cloning the bio? Thanks, Song