On Tue, Apr 14, 2020 at 09:56:16PM -0700, Andrew Morton wrote: > On Tue, 14 Apr 2020 19:18:08 -0700 Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > Hmm. They don't seem that big to me. > > They're really big! v5.7-rc1: 11636 636 224 12496 30d0 fs/iomap/buffered-io.o readahead_v11: 11528 636 224 12388 3064 fs/iomap/buffered-io.o > > __readahead_batch is much bigger, but it's only used by btrfs and fuse, > > and it seemed unfair to make everybody pay the cost for a function only > > used by two filesystems. > > Do we expect more filesystems to use these in the future? I'm honestly not sure. I think it'd be nice to be able to fill a bvec from the page cache directly, but I haven't tried to write that function yet. If so, then it'd be appropriate to move that functionality into the core. > > > The code adds quite a few (inlined!) VM_BUG_ONs. Can we plan to remove > > > them at some stage? Such as, before Linus shouts at us :) > > > > I'd be happy to remove them. Various reviewers said things like "are you > > sure this can't happen?" > > Yeah, these things tend to live for ever. Please add a todo to remove > them after the code has matured? Sure! I'm touching this code some more in the large pages patch set, so I can get rid of it there.
