On Fri, Jan 21, 2022 at 03:02:12PM +0800, Alex Shi wrote: > On Thu, Jan 20, 2022 at 9:28 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > > > On Thu, Jan 20, 2022 at 09:10:20PM +0800, alexs@xxxxxxxxxx wrote: > > > From: Alex Shi <alexs@xxxxxxxxxx> > > > > > > This function could be full replaced by folio_is_file_lru, so no reason > > > to keep a duplicate function. > > > > This is not a helpful way to do this kind of replacement. > > > > Instead of choosing a function to remove and doing a blind replacement, > > choose a call site and convert the whole calling function to use folios. > > Once you've removed all callers, you can remove the wrapper function. > > > > Also, a number of changes here will conflict with patches I've already > > posted. Try doing change_pte_range() in mprotect.c to get a feel for > > how to convert a function entirely to folios. > > Hi Willy, > > Thanks for your comments! > > The patchset did the thing as you required "convert the whole calling > function to use folios. then remove the wrapper function" on yesterday's > Linus and next tree, that included your patchset "Page cache/iomap for 5.17". That's not what I meant. What I meant is you're currently doing: - Find folio wrapper function - Inline it into all callers - Delete wrapper function That creates a lot of churn and not a lot of improvement. What would be helpful is doing: - Find folio wrapper function - Find a caller, convert it from using pages to using folios That's harder, but it actually accomplishes something (ie auditing a function to make it work with folios). These wrapper functions are signals that the callers need to be converted to use folios. > Is the conflicting patch "Enabling large folios for 5.17" or others? Sorry > for can't check everyone, your patches are many. If just the former, I see > you mentioned: "I'd be uncomfortable seeing it merged before 5.18". > Would you point out which of your patches was interfered or blocked? The GUP series was the specific series that this conflicted with. And yes, I have a lot of patches outstanding in this area. That's a sign that small cleanup patches aren't going to be welcomed because they're going to conflict with meaningful patches. > And yes, replacing page functions in change_pte_range is a bit harder, > but it seems it has no much relation with this trival patchset. That is, indeed, the point.
