Commit-ID: 5ba553eff0c3a7c099b1e29a740277a82c0c3314 Gitweb: https://git.kernel.org/tip/5ba553eff0c3a7c099b1e29a740277a82c0c3314 Author: Peter Zijlstra <pet...@infradead.org> AuthorDate: Wed, 29 May 2019 20:36:42 +0000 Committer: Peter Zijlstra <pet...@infradead.org> CommitDate: Thu, 8 Aug 2019 09:09:31 +0200
sched/fair: Expose newidle_balance() For pick_next_task_fair() it is the newidle balance that requires dropping the rq->lock; provided we do put_prev_task() early, we can also detect the condition for doing newidle early. Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Aaron Lu <aaron....@gmail.com> Cc: Valentin Schneider <valentin.schnei...@arm.com> Cc: mi...@kernel.org Cc: Phil Auld <pa...@redhat.com> Cc: Julien Desfossez <jdesfos...@digitalocean.com> Cc: Nishanth Aravamudan <naravamu...@digitalocean.com> Link: https://lkml.kernel.org/r/9e3eb1859b946f03d7e500453a885725b68957ba.1559129225.git.vpil...@digitalocean.com --- kernel/sched/fair.c | 18 ++++++++---------- kernel/sched/sched.h | 4 ++++ 2 files changed, 12 insertions(+), 10 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8ce1b8893947..e7c27eda9f24 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3690,8 +3690,6 @@ static inline unsigned long cfs_rq_load_avg(struct cfs_rq *cfs_rq) return cfs_rq->avg.load_avg; } -static int idle_balance(struct rq *this_rq, struct rq_flags *rf); - static inline unsigned long task_util(struct task_struct *p) { return READ_ONCE(p->se.avg.util_avg); @@ -6878,11 +6876,10 @@ done: __maybe_unused; return p; idle: - update_misfit_status(NULL, rq); - new_tasks = idle_balance(rq, rf); + new_tasks = newidle_balance(rq, rf); /* - * Because idle_balance() releases (and re-acquires) rq->lock, it is + * Because newidle_balance() releases (and re-acquires) rq->lock, it is * possible for any higher priority task to appear. In that case we * must re-start the pick_next_entity() loop. */ @@ -9045,10 +9042,10 @@ out_one_pinned: ld_moved = 0; /* - * idle_balance() disregards balance intervals, so we could repeatedly - * reach this code, which would lead to balance_interval skyrocketting - * in a short amount of time. Skip the balance_interval increase logic - * to avoid that. + * newidle_balance() disregards balance intervals, so we could + * repeatedly reach this code, which would lead to balance_interval + * skyrocketting in a short amount of time. Skip the balance_interval + * increase logic to avoid that. */ if (env.idle == CPU_NEWLY_IDLE) goto out; @@ -9758,7 +9755,7 @@ static inline void nohz_newidle_balance(struct rq *this_rq) { } * idle_balance is called by schedule() if this_cpu is about to become * idle. Attempts to pull tasks from other CPUs. */ -static int idle_balance(struct rq *this_rq, struct rq_flags *rf) +int newidle_balance(struct rq *this_rq, struct rq_flags *rf) { unsigned long next_balance = jiffies + HZ; int this_cpu = this_rq->cpu; @@ -9766,6 +9763,7 @@ static int idle_balance(struct rq *this_rq, struct rq_flags *rf) int pulled_task = 0; u64 curr_cost = 0; + update_misfit_status(NULL, this_rq); /* * We must set idle_stamp _before_ calling idle_balance(), such that we * measure the duration of idle_balance() as idle time. diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index f3c50445bf22..304d98e712bf 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1445,10 +1445,14 @@ static inline void unregister_sched_domain_sysctl(void) } #endif +extern int newidle_balance(struct rq *this_rq, struct rq_flags *rf); + #else static inline void sched_ttwu_pending(void) { } +static inline int newidle_balance(struct rq *this_rq, struct rq_flags *rf) { return 0; } + #endif /* CONFIG_SMP */ #include "stats.h"
