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    SubjectRe: [PATCH] amiflop: get rid of sleep_on calls
    On Wed, Dec 10, 2008 at 01:48:10AM +0100, Andreas Bombe wrote:
    > I think we're not talking about the same problem. If I were to use
    > complete() together with wait_for_completion() there would be a problem
    > if fd_motor_on() can get as far as wait_for_completion() while a
    > previous completion is yet uncompleted. This can not happen for
    > different drives, as the fd_select() would block. If it could happen
    > for the same drive, the complete() would allow only one task to
    > continue. The complete_all() takes care of that.
    >
    > If requests are serialized for a drive so that there won't ever be two
    > running at the same time for certain (thinking about it, it's probable),
    > I could make it a simple complete(). It's hardly worth the risk,
    > however.

    IIRC (have not touched the driver for quite some time) at a
    certain stage all requests for a specific drive are serialized.
    The amiga floppy drives read and write whole tracks only, so
    follow-up acesses are likely to be on the same track and then
    served from the buffer of decoded blocks. I you do wild track
    jumping, it is slower than the original AmigaOS-driver.

    But as I am not sure, and floppy drives are slow anyway, the
    complete_all() won't give any notable performance penalty, I guess.

    Joerg
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