• Hugh Dickins's avatar
    mm: page migration trylock newpage at same level as oldpage · 7db7671f
    Hugh Dickins authored
    Clean up page migration a little by moving the trylock of newpage from
    move_to_new_page() into __unmap_and_move(), where the old page has been
    locked.  Adjust unmap_and_move_huge_page() and balloon_page_migrate()
    accordingly.
    
    But make one kind-of-functional change on the way: whereas trylock of
    newpage used to BUG() if it failed, now simply return -EAGAIN if so.
    Cutting out BUG()s is good, right?  But, to be honest, this is really to
    extend the usefulness of the custom put_new_page feature, allowing a pool
    of new pages to be shared perhaps with racing uses.
    
    Use an "else" instead of that "skip_unmap" label.
    Signed-off-by: default avatarHugh Dickins <hughd@google.com>
    Cc: Christoph Lameter <cl@linux.com>
    Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Vlastimil Babka <vbabka@suse.cz>
    Cc: Davidlohr Bueso <dave@stgolabs.net>
    Cc: Oleg Nesterov <oleg@redhat.com>
    Cc: Sasha Levin <sasha.levin@oracle.com>
    Cc: Dmitry Vyukov <dvyukov@google.com>
    Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
    Acked-by: default avatarRafael Aquini <aquini@redhat.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    7db7671f
balloon_compaction.c 6.58 KB