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    SubjectRe: [PATCH V2 2/2] cpuidle/drivers/menu: Remove get_loadavg in the performance multiplier
    On Thu, Oct 04, 2018 at 02:04:03PM +0200, Daniel Lezcano wrote:
    > The function get_loadavg() returns almost always zero. To be more
    > precise, statistically speaking for a total of 1023379 times passing
    > in the function, the load is equal to zero 1020728 times, greater than
    > 100, 610 times, the remaining is between 0 and 5.
    >
    > In 2011, the get_loadavg() was removed from the Android tree because
    > of the above [1]. At this time, the load was:
    >
    > unsigned long this_cpu_load(void)
    > {
    > struct rq *this = this_rq();
    > return this->cpu_load[0];
    > }
    >
    > In 2014, the code was changed by commit 372ba8cb46b2 (cpuidle: menu: Lookup CPU
    > runqueues less) and the load is:
    >
    > void get_iowait_load(unsigned long *nr_waiters, unsigned long *load)
    > {
    > struct rq *rq = this_rq();
    > *nr_waiters = atomic_read(&rq->nr_iowait);
    > *load = rq->load.weight;
    > }
    >
    > with the same result.
    >
    > Both measurements show using the load in this code path does no matter
    > anymore. Removing it.
    >
    > [1] https://android.googlesource.com/kernel/common/+/4dedd9f124703207895777ac6e91dacde0f7cc17
    >
    > Cc: Peter Zijlstra <peterz@infradead.org>
    > Cc: Todd Kjos <tkjos@google.com>
    > Cc: Joel Fernandes <joelaf@google.com>
    > Cc: Colin Cross <ccross@android.com>
    > Cc: Ramesh Thomas <ramesh.thomas@intel.com>
    > Cc: Mel Gorman <mgorman@suse.de>
    > Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

    Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

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