• Chris Mason's avatar
    Btrfs: Record dirty pages tree-log pages in an extent_io tree · d0c803c4
    Chris Mason authored
    
    
    This is the same way the transaction code makes sure that all the
    other tree blocks are safely on disk.  There's an extent_io tree
    for each root, and any blocks allocated to the tree logs are
    recorded in that tree.
    
    At tree-log sync, the extent_io tree is walked to flush down the
    dirty pages and wait for them.
    
    The main benefit is less time spent walking the tree log and skipping
    clean pages, and getting sequential IO down to the drive.
    Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
    d0c803c4