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    SubjectRe: [PATCH V5] powercap/drivers/idle_injection: Add an idle injection framework
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    On 06/06/2018 14:23, Peter Zijlstra wrote:
    > On Tue, Jun 05, 2018 at 11:16:40AM +0200, Daniel Lezcano wrote:
    >> + atomic_t idle_duration_ms;
    >> + atomic_t run_duration_ms;
    >
    >> + idle_duration_ms = atomic_read(&ii_dev->idle_duration_ms);
    >
    >> + run_duration_ms = atomic_read(&ii_dev->run_duration_ms);
    >
    >> + atomic_set(&ii_dev->run_duration_ms, run_duration_ms);
    >> + atomic_set(&ii_dev->idle_duration_ms, idle_duration_ms);
    >
    >> + *run_duration_ms = atomic_read(&ii_dev->run_duration_ms);
    >> + *idle_duration_ms = atomic_read(&ii_dev->idle_duration_ms);
    >
    >> + if (!atomic_read(&ii_dev->idle_duration_ms))
    >
    >> + if (!atomic_read(&ii_dev->run_duration_ms))
    >
    > What is the point of atomic_t here ?!

    idle_duration and run_duration can be changed from different places at
    the same time. The atomic is here to ensure the read/write are consistent.

    Do you think it is pointless ?




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