• Jens Axboe's avatar
    [PATCH] soft and hard barriers · 719eb3e1
    Jens Axboe authored
    Right now we have one type of barrier in the block layer, and that is
    used mainly for making sure that the io scheduler doesn't reorder
    requests when we don't want it to.  We also need a flag to tell the io
    scheduler and low level queue that this is a barrier.  So basically two
    needs:
    
    o software barrier, prevents the io scheduler from reordering
    o hardware barrier, driver must prevent drive from reordering
    
    So this patch gets rid of REQ_BARRIER and instead adds REQ_SOFTBARRIER
    and REQ_HARDBARRIER.
    719eb3e1
deadline-iosched.c 14 KB