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On Wed, Sep 09, 2026 at 02:17:12PM -0400, Yury Norov wrote: > Split out the logic picking a task from rq to a separate helper, > and get rid of the gotos. > > With GCC 15.2.0 and x86_64_defconfig, the new version saves 96 bytes, > and with defconfig + CONFIG_SCHED_CORE + CONFIG_CFS_BANDWIDTH it saves > 124 bytes. > > No functional changes intended. > > Signed-off-by: Yury Norov > --- > kernel/sched/fair.c | 51 ++++++++++++++++++++++++--------------------- > 1 file changed, 27 insertions(+), 24 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index ade1eceb39b8..ad0c477e58a8 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -10043,39 +10043,42 @@ static void wakeup_preempt_fair(struct rq *rq, struct task_struct *p, int wake_f > resched_curr_lazy(rq); > } > > -struct task_struct *pick_task_fair(struct rq *rq, struct rq_flags *rf) > - __must_hold(__rq_lockp(rq)) > +static struct task_struct *pick_task_fair_rq(struct rq *rq) > { > struct cfs_rq *cfs_rq = &rq->cfs; > struct sched_entity *se; > - struct task_struct *p; > - int new_tasks; > > -again: > - if (!cfs_rq->h_nr_queued) > - goto idle; > + while (cfs_rq->h_nr_queued) { > + /* Might not have done put_prev_entity() */ > + if (cfs_rq->curr && cfs_rq->curr->on_rq) > + update_curr_eevdf(cfs_rq); > > - /* Might not have done put_prev_entity() */ > - if (cfs_rq->curr && cfs_rq->curr->on_rq) > - update_curr_eevdf(cfs_rq); > + se = pick_next_entity(rq, true); > + if (se) > + return task_of(se); > + } > > - se = pick_next_entity(rq, true); > - if (!se) > - goto again; > + return NULL; > +} > > - p = task_of(se); > - return p; > +struct task_struct *pick_task_fair(struct rq *rq, struct rq_flags *rf) > + __must_hold(__rq_lockp(rq)) > +{ > + struct task_struct *p; > + int new_tasks; > > -idle: > - if (sched_core_enabled(rq)) > - return NULL; > + do { > + p = pick_task_fair_rq(rq); > + if (p) > + return p; > > - new_tasks = sched_balance_newidle(rq, rf); > - if (new_tasks < 0) > - return RETRY_TASK; > - if (new_tasks > 0) > - goto again; > - return NULL; > + if (sched_core_enabled(rq)) > + return NULL; > + > + new_tasks = sched_balance_newidle(rq, rf); > + } while (new_tasks > 0); > + > + return new_tasks ? RETRY_TASK : NULL; > } > > static struct task_struct * > -- > 2.53.0