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    SubjectRe: [PATCH 1/6] sched: Fix ttwu_queue_cond()
    On Mon, Jun 15, 2020 at 02:56:55PM +0200, Peter Zijlstra wrote:
    > Where the condition:
    >
    > !cpus_share_cache(smp_processor_id(), cpu)
    >
    > already implies 'cpu != smp_processor_id()', because a CPU always
    > shares cache with itself, the secondary condition added in commit:
    >
    > 2ebb17717550 ("sched/core: Offload wakee task activation if it the wakee is descheduling")
    >
    > voids that implication, resulting in attempting to do local wake-ups
    > through the queue mechanism.
    >
    > Fixes: 2ebb17717550 ("sched/core: Offload wakee task activation if it the wakee is descheduling")
    > Reported-by: Paul E. McKenney <paulmck@kernel.org>
    > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
    > Tested-by: Paul E. McKenney <paulmck@kernel.org>

    Yep, I mistakenly though this would be covered by the self-wakeup check
    early in try_to_wake_up() but it is not

    Acked-by: Mel Gorman <mgorman@suse.de>

    --
    Mel Gorman
    SUSE Labs

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