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charset=us-ascii Content-Disposition: inline In-Reply-To: <20261106151947.3991524-9-vincent.guittot@linaro.org> On Fri, Nov 06, 2026 at 04:19:35PM +0100, Vincent Guittot wrote: > +static struct task_struct *pick_next_pushable_fair_task(struct rq *rq) > +{ > + struct task_struct *p; > + > + if (!has_pushable_tasks(rq)) > + return NULL; > + > + p = plist_first_entry(&rq->cfs.pushable_tasks, > + struct task_struct, pushable_tasks); > + > + WARN_ON_ONCE(rq->cpu != task_cpu(p)); > + WARN_ON_ONCE(task_current(rq, p)); > + WARN_ON_ONCE(p->nr_cpus_allowed <= 1); > + WARN_ON_ONCE(!task_on_rq_queued(p)); > + > + /* > + * Remove task from the pushable list as we try only once after that > + * the task has been put back in enqueued list. > + */ > + plist_del(&p->pushable_tasks, &rq->cfs.pushable_tasks); > + > + return p; > +} This means a task will only be pushed once? After which it needs to be re-enqueued on the runqueue? So if it was found during migrate_disable(), its thereafter stuck? -- this seems a little weird.