sched: Fix load corruption from update_cfs_shares()
As part of enqueue_entity both a new entity weight and its contribution to the queuing cfs_rq / rq are updated. Since update_cfs_shares will only update the queueing weights when the entity is on_rq (which in this case it is not yet), there's a dependency loop here: update_cfs_shares needs account_entity_enqueue to update cfs_rq->load.weight account_entity_enqueue needs the updated weight for the queuing cfs_rq load[*] Fix this and avoid spurious dequeue/enqueues by issuing update_cfs_shares as if we had accounted the enqueue already. This was also resulting in rq->load corruption previously. [*]: this dependency also exists when using the group cfs_rq w/ update_cfs_shares as the weight of the enqueued entity changes without the load being updated. Signed-off-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20101115234937.844900206@google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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