Re: [PATCH v11 10/33] mm: Add folio flag manipulation functions

[David Howells]

Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> wrote:

> These new functions are the folio analogues of the various PageFlags
> functions.  If CONFIG_DEBUG_VM_PGFLAGS is enabled, we check the folio
> is not a tail page at every invocation.  This will also catch the
> PagePoisoned case as a poisoned page has every bit set, which would
> include PageTail.
> 
> This saves 1684 bytes of text with the distro-derived config that
> I'm testing due to removing a double call to compound_head() in
> PageSwapCache().
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Reviewed-by: Christoph Hellwig <hch@xxxxxx>
> Acked-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
> Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx>

Reviewed-by: David Howells <dhowells@xxxxxxxxxx>