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Is this just to reduce the >>> time window >>> for a race? >>> >>> If the above is true, then, there is a negligible window between >>> xas_load() and >>> xas_reload(), because only xas_retry() exists between them, so why >>> to even reload()? >>> >>> Thanks, >>> Dev >> >> I do not completely remember our discussion in THP Cabal; I recall >> David Howells maybe >> saying that the folios are already locked, so it is safe to do >> xas_load and then do >> a folio_get()? Even if we remove the redundant xas_reload(), I still >> don't understand >> why we won't need xas_reload() at least after folio_get()? > > I think the points where > > (a) this should go all away soon > > (b) there is the expectation that the folios cannot get truncated >     concurrently. So we can do an unconditional folio_get(), don't have >     to check folio->mapping etc. Well...pretty sure the file read path is taking the inode->i_rwsem or i_lock somewhere, to synchronize with truncation/reclaim, can't figure out where. Reclaim takes the i_lock in __remove_mapping and then freezes the folio reference, so the read path must lock i_lock somewhere. > > (c) The xas_reload() seems unnecessary and can be dropped. >