The following commit has been merged into the sched/core branch of tip: Commit-ID: 457d1f465778ccb5f14f7d7a62245e41d12a3804 Gitweb: https://git.kernel.org/tip/457d1f465778ccb5f14f7d7a62245e41d12a3804 Author: Chen Yu <[email protected]> AuthorDate: Tue, 21 Apr 2020 18:50:43 +08:00 Committer: Peter Zijlstra <[email protected]> CommitterDate: Thu, 30 Apr 2020 20:14:40 +02:00
sched: Extract the task putting code from pick_next_task() Introduce a new function put_prev_task_balance() to do the balance when necessary, and then put previous task back to the run queue. This function is extracted from pick_next_task() to prepare for future usage by other type of task picking logic. No functional change. Suggested-by: Peter Zijlstra <[email protected]> Signed-off-by: Chen Yu <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Reviewed-by: Valentin Schneider <[email protected]> Reviewed-by: Vincent Guittot <[email protected]> Reviewed-by: Steven Rostedt (VMware) <[email protected]> Link: https://lkml.kernel.org/r/5a99860cf66293db58a397d6248bcb2eee326776.1587464698.git.yu.c.c...@intel.com --- kernel/sched/core.c | 39 +++++++++++++++++++++++---------------- 1 file changed, 23 insertions(+), 16 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 9a2fbf9..2e6ba9e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3899,6 +3899,28 @@ static inline void schedule_debug(struct task_struct *prev, bool preempt) schedstat_inc(this_rq()->sched_count); } +static void put_prev_task_balance(struct rq *rq, struct task_struct *prev, + struct rq_flags *rf) +{ +#ifdef CONFIG_SMP + const struct sched_class *class; + /* + * We must do the balancing pass before put_prev_task(), such + * that when we release the rq->lock the task is in the same + * state as before we took rq->lock. + * + * We can terminate the balance pass as soon as we know there is + * a runnable task of @class priority or higher. + */ + for_class_range(class, prev->sched_class, &idle_sched_class) { + if (class->balance(rq, prev, rf)) + break; + } +#endif + + put_prev_task(rq, prev); +} + /* * Pick up the highest-prio task: */ @@ -3932,22 +3954,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) } restart: -#ifdef CONFIG_SMP - /* - * We must do the balancing pass before put_next_task(), such - * that when we release the rq->lock the task is in the same - * state as before we took rq->lock. - * - * We can terminate the balance pass as soon as we know there is - * a runnable task of @class priority or higher. - */ - for_class_range(class, prev->sched_class, &idle_sched_class) { - if (class->balance(rq, prev, rf)) - break; - } -#endif - - put_prev_task(rq, prev); + put_prev_task_balance(rq, prev, rf); for_each_class(class) { p = class->pick_next_task(rq);
