On Sat, May 01, 2021 at 02:38:50PM -0700, John Hubbard wrote: > On 4/30/21 6:32 PM, Nicholas Piggin wrote: > ... > > > > - Big renaming (thanks to peterz): > > > > - PageFoo() becomes folio_foo() > > > > - SetFolioFoo() becomes folio_set_foo() > > > > - ClearFolioFoo() becomes folio_clear_foo() > > > > - __SetFolioFoo() becomes __folio_set_foo() > > > > - __ClearFolioFoo() becomes __folio_clear_foo() > > > > - TestSetPageFoo() becomes folio_test_set_foo() > > > > - TestClearPageFoo() becomes folio_test_clear_foo() > > > > - PageHuge() is now folio_hugetlb() > > > > If you rename these things at the same time, can you make it clear > > they're flags (folio_flag_set_foo())? The weird camel case accessors at > > least make that clear (after you get to know them). > > In addition to pointing out that the name was a page flag, the weird > camel case also meant, "if you try to search for this symbol, you will > be defeated", because the darn thing is constructed via macro > concatenation. I've always hated that, FWIW. And you can't add kernel-doc for them because kernel-doc doesn't understand cpp. So my current plan (quoting my other email): folio_dirty() -- defined in page-flags.h would have kernel-doc, would be greppable folio_test_set_dirty_flag() folio_test_clear_dirty_flag() __folio_clear_dirty_flag() __folio_set_dirty_flag() folio_clear_dirty_flag() folio_set_dirty_flag() -- generated in filemap.h under #ifndef MODULE would not have kernel-doc, would not be greppable, would only be used in core vfs and core mm. folio_mark_dirty() -- declared in mm.h (this is rare; turns out all kinds of crap wants to mark pages as being dirty) folio_clear_dirty_for_io() -- declared in filemap.h already have kernel-doc, are greppable, used by filesystems and sometimes other random code. > Except that over time, it turned out to be not quite that simple, and > people started adding functionality. So now it's "cannot find it, and > it's also got little goodies hiding in there--maybe!". I also don't like that. With what I'm thinking, there are no special cases hidden in the autogenerated names. Special things like the current SetPageUptodate would be in folio_mark_uptodate() and filesystems couldn't even call folio_set_uptodate(). > Given all that, I'd argue for either: > b) changing a bunch of the items to actual written-out names. What's > the harm? We'd end up with a longer file, but one could grep or > cscope for the names. I hope the above makes you happy -- everything a filesystem author needs gets kernel-doc. People working inside the VM/VFS still get exposed to undocumented folio_test_set_foo_flag(), but it's all regular and autogenerated.
