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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jinchao, On 12/13/23 3:12 PM, WangJinchao Wrote: > The code below is duplicated in two for loops and need to be > consolidated It doesn't need to, but it can actually bring some benefit from the point of view of text size, especially in warehouse-scale computers where icache is extremely contended. add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-56 (-56) Function old new delta enqueue_task_fair 936 880 -56 Total: Before=64899, After=64843, chg -0.09% > > Signed-off-by: WangJinchao > --- > kernel/sched/fair.c | 31 ++++++++----------------------- > 1 file changed, 8 insertions(+), 23 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index d7a3c63a2171..e1373bfd4f2e 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -6681,30 +6681,15 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags) > cpufreq_update_util(rq, SCHED_CPUFREQ_IOWAIT); > > for_each_sched_entity(se) { > - if (se->on_rq) > - break; > cfs_rq = cfs_rq_of(se); > - enqueue_entity(cfs_rq, se, flags); > - > - cfs_rq->h_nr_running++; > - cfs_rq->idle_h_nr_running += idle_h_nr_running; > - > - if (cfs_rq_is_idle(cfs_rq)) > - idle_h_nr_running = 1; > - > - /* end evaluation on encountering a throttled cfs_rq */ > - if (cfs_rq_throttled(cfs_rq)) > - goto enqueue_throttle; > - > - flags = ENQUEUE_WAKEUP; > - } > - > - for_each_sched_entity(se) { > - cfs_rq = cfs_rq_of(se); > - > - update_load_avg(cfs_rq, se, UPDATE_TG); > - se_update_runnable(se); > - update_cfs_group(se); > + if (se->on_rq) { > + update_load_avg(cfs_rq, se, UPDATE_TG); > + se_update_runnable(se); > + update_cfs_group(se); > + } else { > + enqueue_entity(cfs_rq, se, flags); > + flags = ENQUEUE_WAKEUP; > + } > > cfs_rq->h_nr_running++; > cfs_rq->idle_h_nr_running += idle_h_nr_running; I have no strong opinon about this 'cleanup', but the same pattern can also be found in dequeue_task_fair() and I think it would be better get them synchronized. Thanks, Abel