On Tue, Aug 25, 2020 at 10:09:02AM +1000, Dave Chinner wrote: > On Mon, Aug 24, 2020 at 03:55:07PM +0100, Matthew Wilcox (Oracle) wrote: > > Instead of counting bio segments, count the number of bytes submitted. > > This insulates us from the block layer's definition of what a 'same page' > > is, which is not necessarily clear once THPs are involved. > > I'd like to see a comment on the definition of struct iomap_page to > indicate that read_count (and write count) reflect the byte count of > IO currently in flight on the page, not an IO count, because THP > makes tracking this via bio state hard. Otherwise it is not at all > obvious why it is done and why it is intentional... Agreed. :) --D > Otherwise the code looks OK. > > Cheers, > > Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx
