Merge "core_ctl: Harden the adjustment_possible() check for unisolation" into msm-4.9 (342d14c4) · Commits · e / devices / android_kernel_fairphone_FP3

kernel/sched/core_ctl.c

+23 −2

Original line number	Diff line number	Diff line
		@@ -35,6 +35,7 @@ struct cluster_data {
		unsigned int busy_down_thres[MAX_CPUS_PER_CLUSTER];
		unsigned int active_cpus;
		unsigned int num_cpus;
		unsigned int nr_isolated_cpus;
		cpumask_t cpu_mask;
		unsigned int need_cpus;
		unsigned int task_thres;
		@@ -297,6 +298,9 @@ static ssize_t show_global_state(const struct cluster_data state, char buf)
		"\tActive CPUs: %u\n", get_active_cpu_count(cluster));
		count += snprintf(buf + count, PAGE_SIZE - count,
		"\tNeed CPUs: %u\n", cluster->need_cpus);
		count += snprintf(buf + count, PAGE_SIZE - count,
		"\tNr isolated CPUs: %u\n",
		cluster->nr_isolated_cpus);
		count += snprintf(buf + count, PAGE_SIZE - count,
		"\tBoost: %u\n", (unsigned int) cluster->boost);
		}
		@@ -533,7 +537,7 @@ static bool adjustment_possible(const struct cluster_data *cluster,
		unsigned int need)
		{
		return (need < cluster->active_cpus \|\| (need > cluster->active_cpus &&
		sched_isolate_count(&cluster->cpu_mask, false)));
		cluster->nr_isolated_cpus));
		}

		static bool eval_need(struct cluster_data *cluster)
		@@ -724,6 +728,7 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need)
		struct cpu_data c, tmp;
		unsigned long flags;
		unsigned int num_cpus = cluster->num_cpus;
		unsigned int nr_isolated = 0;

		/*
		* Protect against entry being removed (and added at tail) by other
		@@ -748,12 +753,14 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need)
		if (!sched_isolate_cpu(c->cpu)) {
		c->isolated_by_us = true;
		move_cpu_lru(c);
		nr_isolated++;
		} else {
		pr_debug("Unable to isolate CPU%u\n", c->cpu);
		}
		cluster->active_cpus = get_active_cpu_count(cluster);
		spin_lock_irqsave(&state_lock, flags);
		}
		cluster->nr_isolated_cpus += nr_isolated;
		spin_unlock_irqrestore(&state_lock, flags);

		/*
		@@ -763,6 +770,7 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need)
		if (cluster->active_cpus <= cluster->max_cpus)
		return;

		nr_isolated = 0;
		num_cpus = cluster->num_cpus;
		spin_lock_irqsave(&state_lock, flags);
		list_for_each_entry_safe(c, tmp, &cluster->lru, sib) {
		@@ -780,12 +788,14 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need)
		if (!sched_isolate_cpu(c->cpu)) {
		c->isolated_by_us = true;
		move_cpu_lru(c);
		nr_isolated++;
		} else {
		pr_debug("Unable to isolate CPU%u\n", c->cpu);
		}
		cluster->active_cpus = get_active_cpu_count(cluster);
		spin_lock_irqsave(&state_lock, flags);
		}
		cluster->nr_isolated_cpus += nr_isolated;
		spin_unlock_irqrestore(&state_lock, flags);

		}
		@@ -796,6 +806,7 @@ static void __try_to_unisolate(struct cluster_data *cluster,
		struct cpu_data c, tmp;
		unsigned long flags;
		unsigned int num_cpus = cluster->num_cpus;
		unsigned int nr_unisolated = 0;

		/*
		* Protect against entry being removed (and added at tail) by other
		@@ -820,12 +831,14 @@ static void __try_to_unisolate(struct cluster_data *cluster,
		if (!sched_unisolate_cpu(c->cpu)) {
		c->isolated_by_us = false;
		move_cpu_lru(c);
		nr_unisolated++;
		} else {
		pr_debug("Unable to unisolate CPU%u\n", c->cpu);
		}
		cluster->active_cpus = get_active_cpu_count(cluster);
		spin_lock_irqsave(&state_lock, flags);
		}
		cluster->nr_isolated_cpus -= nr_unisolated;
		spin_unlock_irqrestore(&state_lock, flags);
		}

		@@ -891,6 +904,8 @@ static int __ref cpu_callback(struct notifier_block *nfb,
		struct cpu_data *state = &per_cpu(cpu_state, cpu);
		struct cluster_data *cluster = state->cluster;
		unsigned int need;
		bool do_wakeup, unisolated = false;
		unsigned long flags;

		if (unlikely(!cluster \|\| !cluster->inited))
		return NOTIFY_DONE;
		@@ -916,6 +931,7 @@ static int __ref cpu_callback(struct notifier_block *nfb,
		if (state->isolated_by_us) {
		sched_unisolate_cpu_unlocked(cpu);
		state->isolated_by_us = false;
		unisolated = true;
		}

		/* Move a CPU to the end of the LRU when it goes offline. */
		@@ -929,7 +945,12 @@ static int __ref cpu_callback(struct notifier_block *nfb,
		}

		need = apply_limits(cluster, cluster->need_cpus);
		if (adjustment_possible(cluster, need))
		spin_lock_irqsave(&state_lock, flags);
		if (unisolated)
		cluster->nr_isolated_cpus--;
		do_wakeup = adjustment_possible(cluster, need);
		spin_unlock_irqrestore(&state_lock, flags);
		if (do_wakeup)
		wake_up_core_ctl_thread(cluster);

		return NOTIFY_OK;