On Sat, Nov 14, 2020 at 11:21:33AM +0100, Christoph Hellwig wrote: > On Thu, Nov 12, 2020 at 09:26:38PM +0000, Matthew Wilcox (Oracle) wrote: > > + pvec->nr = ret; > > return ret; > > Do we need to return the number of found entries in addition to storing > it in the pagevec? We really only need a bool -- is pvec->nr zero or not. But we have the number calculated so we may as well return it. All the current find_*() behave this way and I haven't seen enough reason to change it yet. Making it return void just makes the callers uglier. I have a batch of patches to do something similar for find_get_pages / find_get_pages_range / pagevec_lookup / pagevec_lookup_range, but I don't need them for the THP patchset, so I haven't sent them yet.