• Alexander Lobakin's avatar
    page_pool: make sure frag API fields don't span between cachelines · 1f20a576
    Alexander Lobakin authored
    After commit 5027ec19
    
     ("net: page_pool: split the page_pool_params
    into fast and slow") that made &page_pool contain only "hot" params at
    the start, cacheline boundary chops frag API fields group in the middle
    again.
    To not bother with this each time fast params get expanded or shrunk,
    let's just align them to `4 * sizeof(long)`, the closest upper pow-2 to
    their actual size (2 longs + 1 int). This ensures 16-byte alignment for
    the 32-bit architectures and 32-byte alignment for the 64-bit ones,
    excluding unnecessary false-sharing.
    ::page_state_hold_cnt is used quite intensively on hotpath no matter if
    frag API is used, so move it to the newly created hole in the first
    cacheline.
    Signed-off-by: default avatarAlexander Lobakin <aleksander.lobakin@intel.com>
    Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
    1f20a576
page_pool.c 27.4 KB