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    SubjectRe: V4L2 drivers: potentially dangerous and inefficient msecs_to_jiffies() calculation
    Hi,

    On Mon, Sep 14, 2009 at 11:34:40PM +0200, Jiri Slaby wrote:
    > On 09/14/2009 11:07 PM, Andreas Mohr wrote:
    > > ./drivers/media/video/zc0301/zc0301_core.c
    > > do
    > > cam->module_param.frame_timeout *
    > > 1000 * msecs_to_jiffies(1) );
    > > multiple times each.
    > > What they should do instead is
    > > frame_timeout * msecs_to_jiffies(1000), I'd think.
    >
    > In fact, msecs_to_jiffies(frame_timeout * 1000) makes much more sense.

    Heh, right, even a bit better ;)

    > > msecs_to_jiffies(1) is quite a bit too boldly assuming
    > > that all of the msecs_to_jiffies(x) implementation branches
    > > always round up.
    >
    > They do, don't they?

    I'd hope so, but a slight risk remains, you never know,
    especially with 4+ or so variants...

    Andreas Mohr


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