lkml.org 
[lkml]   [2021]   [Jan]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v2 05/27] mm: Add put_folio
    Date
    If we know we have a folio, we can call put_folio() instead of put_page()
    and save the overhead of calling compound_head(). Also skips the
    devmap checks.

    Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
    ---
    include/linux/mm.h | 15 ++++++++++-----
    1 file changed, 10 insertions(+), 5 deletions(-)

    diff --git a/include/linux/mm.h b/include/linux/mm.h
    index 5b071c226fd6..4d135b62a2b6 100644
    --- a/include/linux/mm.h
    +++ b/include/linux/mm.h
    @@ -1217,9 +1217,15 @@ static inline __must_check bool try_get_page(struct page *page)
    return true;
    }

    +static inline void put_folio(struct folio *folio)
    +{
    + if (put_page_testzero(&folio->page))
    + __put_page(&folio->page);
    +}
    +
    static inline void put_page(struct page *page)
    {
    - page = compound_head(page);
    + struct folio *folio = page_folio(page);

    /*
    * For devmap managed pages we need to catch refcount transition from
    @@ -1227,13 +1233,12 @@ static inline void put_page(struct page *page)
    * need to inform the device driver through callback. See
    * include/linux/memremap.h and HMM for details.
    */
    - if (page_is_devmap_managed(page)) {
    - put_devmap_managed_page(page);
    + if (page_is_devmap_managed(&folio->page)) {
    + put_devmap_managed_page(&folio->page);
    return;
    }

    - if (put_page_testzero(page))
    - __put_page(page);
    + put_folio(folio);
    }

    /*
    --
    2.29.2
    \
     
     \ /
      Last update: 2021-01-18 18:14    [W:4.174 / U:0.256 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site