[lkml]   [1999]   [Mar]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: disk head scheduling

    On Wed, 24 Mar 1999, Stephen C. Tweedie wrote:

    > Hi,
    > On Tue, 23 Mar 1999 21:41:56 +0100 (MET), Gerard Roudier
    > <> said:
    > > A) Linux is doing IOs per block or per page from the kernel and we need
    > > to coalesce and sort this small virtual IOs somewhere.
    > > B) The Linux design is, at the moment, to perform this work from
    > > ll_rw_blk.
    > > The get_queue() only function looks like some band-aid for IDE to me.
    > > Since too partial design is bad design I am not going to use this method.
    > You really have to justify that statement!

    Indeed. It seems fairly clean to me - I was actually thinking
    that the idea could be significantly enhanced such that get_queue instead
    returns a pointer to a structure:

    struct request_queue
    struct request * current_request;
    request_fn_proc * request_fn;
    make_request_fn * merge_fn;
    spinlock_t io_request_lock;
    void * queuedata;

    such that each queue has it's own queue head (obviously - this is
    effectively all this structure contained before), function pointers for
    requeust queueing, mergeing of new commands, a lock (to be used in place
    of io_request_lock), and finally an abstract pointer that request_fn()
    could use (for whatever purpose the actual queue handler wanted).


    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:51    [W:0.021 / U:0.096 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site