Re: [PATCH v14 018/138] mm/filemap: Add folio_lock()

From: Mike Rapoport
Date: Tue Jul 20 2021 - 06:55:24 EST


On Thu, Jul 15, 2021 at 04:35:04AM +0100, Matthew Wilcox (Oracle) wrote:
> This is like lock_page() but for use by callers who know they have a folio.
> Convert __lock_page() to be __folio_lock(). This saves one call to
> compound_head() per contended call to lock_page().
>
> Saves 455 bytes of text; mostly from improved register allocation and
> inlining decisions. __folio_lock is 59 bytes while __lock_page was 79.
>
> 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>
> ---
> include/linux/pagemap.h | 24 +++++++++++++++++++-----
> mm/filemap.c | 29 +++++++++++++++--------------
> 2 files changed, 34 insertions(+), 19 deletions(-)

Acked-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>