• Nick Piggin's avatar
    fs: Implement lazy LRU updates for inodes · 9e38d86f
    Nick Piggin authored
    Convert the inode LRU to use lazy updates to reduce lock and
    cacheline traffic.  We avoid moving inodes around in the LRU list
    during iget/iput operations so these frequent operations don't need
    to access the LRUs. Instead, we defer the refcount checks to
    reclaim-time and use a per-inode state flag, I_REFERENCED, to tell
    reclaim that iget has touched the inode in the past. This means that
    only reclaim should be touching the LRU with any frequency, hence
    significantly reducing lock acquisitions and the amount contention
    on LRU updates.
    This also removes the inode_in_use list, which means we now only
    have one list for tracking the inode LRU status. This makes it much
    simpler to split out the LRU list operations under it's own lock.
    Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
    Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
    Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
    Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
inode.c 42.3 KB