lkml.org 
[lkml]   [2009]   [Oct]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [RFC V2 PATCH 2/5] cfq-iosched: preparation to handle multiple service trees
    Date
    Corrado Zoccolo <czoccolo@gmail.com> writes:

    > Hi Jeff,
    > On Wed, Oct 21, 2009 at 5:31 PM, Jeff Moyer <jmoyer@redhat.com> wrote:
    >> Corrado Zoccolo <czoccolo@gmail.com> writes:
    >>
    >>> We embed a pointer to the service tree in each queue, to handle multiple
    >>> service trees easily.
    >>> Service trees are enriched with a counter.
    >>> cfq_add_rq_rb is invoked after putting the rq in the fifo, to ensure
    >>> that all fields in rq are properly initialized.
    >>>
    >>> @@ -115,6 +116,9 @@ struct cfq_queue {
    >>>       unsigned short ioprio_class, org_ioprio_class;
    >>>
    >>>       pid_t pid;
    >>> +
    >>> +     struct cfq_rb_root *service_tree;
    >>> +     struct cfq_io_context *cic;
    >>>  };
    >>
    >> This change worries me.  For async queues, there is not a 1:1 mapping
    >> between cfqq and cic.
    >
    > Currently, I need it only for sync queues. And it is used only to
    > determine if a queue is seeky, so if we can mark it in the queue
    > instead of the cic, this will not be needed any more.

    Ah ha! I have the same requirement for breaking the queues apart, so I
    think this won't be an issue.

    Thanks!
    Jeff
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2009-10-21 18:29    [W:0.055 / U:30.880 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site