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    SubjectRe: vmevent: question?
    On 05/03/2012 05:07 PM, Pekka Enberg wrote:

    > On Thu, May 3, 2012 at 10:57 AM, Minchan Kim <minchan@kernel.org> wrote:
    >> Sorry for my poor explanation.
    >> My point is when userspace get vmevent_event by reading fd, it could enumerate
    >> several attribute all at once.
    >> Then, one of attribute(call A) made by vmevent_match in kernel and other attributes(call B, C, D)
    >> are just extra for convenience. Because there is time gap when kernel get attribute values, B,C,D could be stale.
    >> Then, how can user determine which event is really triggered? A or B or C or D?
    >> Which event really happens?
    >
    > Right. Mark the matching values with something like
    > VMEVENT_ATTR_STATE_CAPTURED should be sufficient?


    Seems to be good and we have to notice to user by document
    "Except VMEVENT_ATTR_STATE_CAPTURED, all attributes's value could be stale.
    So, don't be deceived. Please ignore if you need"

    First of all, let make CAPTURED state could be exact.

    -----
    > Q 2. Is it okay although value when vmevent_match check happens is different with
    > vmevent_sample_attr in vmevent_sample's for loop?
    > I think it's not good.
    Yeah, that's just silly and needs fixing.
    -----

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    --
    Kind regards,
    Minchan Kim


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