Merge "sched: Don't update idle_cpus_mask during core isolation" (ab0a48ea) · Commits · e / devices / android_kernel_fairphone_FP3

kernel/sched/core.c

+0 −6

Original line number	Diff line number	Diff line
		@@ -5958,12 +5958,6 @@ int do_isolation_work_cpu_stop(void *data)
		set_rq_online(rq);
		raw_spin_unlock(&rq->lock);

		/*
		* We might have been in tickless state. Clear NOHZ flags to avoid
		* us being kicked for helping out with balancing
		*/
		nohz_balance_clear_nohz_mask(cpu);

		clear_walt_request(cpu);
		local_irq_enable();
		return 0;

kernel/sched/fair.c

+22 −14

Original line number	Diff line number	Diff line
		@@ -9888,6 +9888,8 @@ static inline int find_new_ilb(int type)
		if (sd) {
		cpumask_and(&cpumask, nohz.idle_cpus_mask,
		sched_domain_span(sd));
		cpumask_andnot(&cpumask, &cpumask,
		cpu_isolated_mask);
		ilb = cpumask_first(&cpumask);
		}
		rcu_read_unlock();
		@@ -9896,8 +9898,11 @@ static inline int find_new_ilb(int type)
		if (!energy_aware() \|\|
		(capacity_orig_of(cpu) ==
		cpu_rq(cpu)->rd->max_cpu_capacity.val \|\|
		cpu_overutilized(cpu)))
		ilb = cpumask_first(nohz.idle_cpus_mask);
		cpu_overutilized(cpu))) {
		cpumask_andnot(&cpumask, nohz.idle_cpus_mask,
		cpu_isolated_mask);
		ilb = cpumask_first(&cpumask);
		}
		}

		if (ilb < nr_cpu_ids && idle_cpu(ilb))
		@@ -9934,21 +9939,16 @@ static void nohz_balancer_kick(int type)
		return;
		}

		void nohz_balance_clear_nohz_mask(int cpu)
		{
		if (likely(cpumask_test_cpu(cpu, nohz.idle_cpus_mask))) {
		cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
		atomic_dec(&nohz.nr_cpus);
		}
		}

		void nohz_balance_exit_idle(unsigned int cpu)
		{
		if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
		/*
		* Completely isolated CPUs don't ever set, so we must test.
		*/
		nohz_balance_clear_nohz_mask(cpu);
		if (likely(cpumask_test_cpu(cpu, nohz.idle_cpus_mask))) {
		cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
		atomic_dec(&nohz.nr_cpus);
		}
		clear_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
		}
		}
		@@ -10223,6 +10223,7 @@ static inline bool nohz_kick_needed(struct rq rq, int type)
		int nr_busy;
		int cpu = rq->cpu;
		bool kick = false;
		cpumask_t cpumask;

		if (unlikely(rq->idle_balance))
		return false;
		@@ -10238,7 +10239,8 @@ static inline bool nohz_kick_needed(struct rq rq, int type)
		* None are in tickless mode and hence no need for NOHZ idle load
		* balancing.
		*/
		if (likely(!atomic_read(&nohz.nr_cpus)))
		cpumask_andnot(&cpumask, nohz.idle_cpus_mask, cpu_isolated_mask);
		if (cpumask_empty(&cpumask))
		return false;

		if (time_before(now, nohz.next_balance))
		@@ -10272,8 +10274,7 @@ static inline bool nohz_kick_needed(struct rq rq, int type)
		}

		sd = rcu_dereference(per_cpu(sd_asym, cpu));
		if (sd && (cpumask_first_and(nohz.idle_cpus_mask,
		sched_domain_span(sd)) < cpu)) {
		if (sd && (cpumask_first_and(&cpumask, sched_domain_span(sd)) < cpu)) {
		kick = true;
		goto unlock;
		}
		@@ -10296,6 +10297,13 @@ static __latent_entropy void run_rebalance_domains(struct softirq_action *h)
		enum cpu_idle_type idle = this_rq->idle_balance ?
		CPU_IDLE : CPU_NOT_IDLE;

		/*
		* Since core isolation doesn't update nohz.idle_cpus_mask, there
		* is a possibility this nohz kicked cpu could be isolated. Hence
		* return if the cpu is isolated.
		*/
		if (cpu_isolated(this_rq->cpu))
		return;
		/*
		* If this cpu has a pending nohz_balance_kick, then do the
		* balancing on behalf of the other idle cpus whose ticks are

kernel/sched/sched.h

+0 −1

Original line number	Diff line number	Diff line
		@@ -1444,7 +1444,6 @@ extern void init_max_cpu_capacity(struct max_cpu_capacity *mcc);
		extern void update_group_capacity(struct sched_domain *sd, int cpu);

		extern void trigger_load_balance(struct rq *rq);
		extern void nohz_balance_clear_nohz_mask(int cpu);

		extern void set_cpus_allowed_common(struct task_struct p, const struct cpumask new_mask);