• Tejun Heo's avatar
    writeback: implement and use inode_congested() · 703c2708
    Tejun Heo authored
    In several places, bdi_congested() and its wrappers are used to
    determine whether more IOs should be issued.  With cgroup writeback
    support, this question can't be answered solely based on the bdi
    (backing_dev_info).  It's dependent on whether the filesystem and bdi
    support cgroup writeback and the blkcg the inode is associated with.
    This patch implements inode_congested() and its wrappers which take
    @inode and determines the congestion state considering cgroup
    writeback.  The new functions replace bdi_*congested() calls in places
    where the query is about specific inode and task.
    There are several filesystem users which also fit this criteria but
    they should be updated when each filesystem implements cgroup
    writeback support.
    v2: Now that a given inode is associated with only one wb, congestion
        state can be determined independent from the asking task.  Drop
        @task.  Spotted by Vivek.  Also, converted to take @inode instead
        of @mapping and renamed to inode_congested().
    Signed-off-by: default avatarTejun Heo <tj@kernel.org>
    Cc: Jens Axboe <axboe@kernel.dk>
    Cc: Jan Kara <jack@suse.cz>
    Cc: Vivek Goyal <vgoyal@redhat.com>
    Signed-off-by: default avatarJens Axboe <axboe@fb.com>
fadvise.c 3.72 KB