sched/isolation: Use single feature type while referring to housekeeping cpumask

Refer to housekeeping APIs using single feature types instead of flags.
This prevents from passing multiple isolation features at once to
housekeeping interfaces, which soon won't be possible anymore as each
isolation features will have their own cpumask.

Signed-off-by: Frederic Weisbecker <[e-mail]>
Signed-off-by: Peter Zijlstra (Intel) <[e-mail]>
Reviewed-by: Juri Lelli <[e-mail]>
Reviewed-by: Phil Auld <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

arch/x86/kernel/cpu/aperfmperf.c

···
 	if (!boot_cpu_has(X86_FEATURE_APERFMPERF))
 		return 0;
 
-	if (!housekeeping_cpu(cpu, HK_FLAG_MISC))
+	if (!housekeeping_cpu(cpu, HK_TYPE_MISC))
 		return 0;
 
 	if (rcu_is_idle_cpu(cpu))
···
 		return;
 
 	for_each_online_cpu(cpu) {
-		if (!housekeeping_cpu(cpu, HK_FLAG_MISC))
+		if (!housekeeping_cpu(cpu, HK_TYPE_MISC))
 			continue;
 		if (rcu_is_idle_cpu(cpu))
 			continue; /* Idle CPUs are completely uninteresting. */
···
 	if (!boot_cpu_has(X86_FEATURE_APERFMPERF))
 		return 0;
 
-	if (!housekeeping_cpu(cpu, HK_FLAG_MISC))
+	if (!housekeeping_cpu(cpu, HK_TYPE_MISC))
 		return 0;
 
 	if (aperfmperf_snapshot_cpu(cpu, ktime_get(), true))

arch/x86/kvm/x86.c

···
 	}
 
 	if (pi_inject_timer == -1)
-		pi_inject_timer = housekeeping_enabled(HK_FLAG_TIMER);
+		pi_inject_timer = housekeeping_enabled(HK_TYPE_TIMER);
 #ifdef CONFIG_X86_64
 	pvclock_gtod_register_notifier(&pvclock_gtod_notifier);
 

drivers/base/cpu.c

···
 		return -ENOMEM;
 
 	cpumask_andnot(isolated, cpu_possible_mask,
-		       housekeeping_cpumask(HK_FLAG_DOMAIN));
+		       housekeeping_cpumask(HK_TYPE_DOMAIN));
 	len = sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(isolated));
 
 	free_cpumask_var(isolated);

drivers/pci/pci-driver.c

···
 			goto out;
 		}
 		cpumask_and(wq_domain_mask,
-			    housekeeping_cpumask(HK_FLAG_WQ),
-			    housekeeping_cpumask(HK_FLAG_DOMAIN));
+			    housekeeping_cpumask(HK_TYPE_WQ),
+			    housekeeping_cpumask(HK_TYPE_DOMAIN));
 
 		cpu = cpumask_any_and(cpumask_of_node(node),
 				      wq_domain_mask);

include/linux/sched/isolation.h

···
 #include <linux/init.h>
 #include <linux/tick.h>
 
-enum hk_flags {
-	HK_FLAG_TIMER		= 1,
-	HK_FLAG_RCU		= (1 << 1),
-	HK_FLAG_MISC		= (1 << 2),
-	HK_FLAG_SCHED		= (1 << 3),
-	HK_FLAG_TICK		= (1 << 4),
-	HK_FLAG_DOMAIN		= (1 << 5),
-	HK_FLAG_WQ		= (1 << 6),
-	HK_FLAG_MANAGED_IRQ	= (1 << 7),
-	HK_FLAG_KTHREAD		= (1 << 8),
+enum hk_type {
+	HK_TYPE_TIMER,
+	HK_TYPE_RCU,
+	HK_TYPE_MISC,
+	HK_TYPE_SCHED,
+	HK_TYPE_TICK,
+	HK_TYPE_DOMAIN,
+	HK_TYPE_WQ,
+	HK_TYPE_MANAGED_IRQ,
+	HK_TYPE_KTHREAD,
+	HK_TYPE_MAX
 };
 
 #ifdef CONFIG_CPU_ISOLATION
 DECLARE_STATIC_KEY_FALSE(housekeeping_overridden);
-extern int housekeeping_any_cpu(enum hk_flags flags);
-extern const struct cpumask *housekeeping_cpumask(enum hk_flags flags);
-extern bool housekeeping_enabled(enum hk_flags flags);
-extern void housekeeping_affine(struct task_struct *t, enum hk_flags flags);
-extern bool housekeeping_test_cpu(int cpu, enum hk_flags flags);
+extern int housekeeping_any_cpu(enum hk_type type);
+extern const struct cpumask *housekeeping_cpumask(enum hk_type type);
+extern bool housekeeping_enabled(enum hk_type type);
+extern void housekeeping_affine(struct task_struct *t, enum hk_type type);
+extern bool housekeeping_test_cpu(int cpu, enum hk_type type);
 extern void __init housekeeping_init(void);
 
 #else
 
-static inline int housekeeping_any_cpu(enum hk_flags flags)
+static inline int housekeeping_any_cpu(enum hk_type type)
 {
 	return smp_processor_id();
 }
 
-static inline const struct cpumask *housekeeping_cpumask(enum hk_flags flags)
+static inline const struct cpumask *housekeeping_cpumask(enum hk_type type)
 {
 	return cpu_possible_mask;
 }
 
-static inline bool housekeeping_enabled(enum hk_flags flags)
+static inline bool housekeeping_enabled(enum hk_type type)
 {
 	return false;
 }
 
 static inline void housekeeping_affine(struct task_struct *t,
-				       enum hk_flags flags) { }
+				       enum hk_type type) { }
 static inline void housekeeping_init(void) { }
 #endif /* CONFIG_CPU_ISOLATION */
 
-static inline bool housekeeping_cpu(int cpu, enum hk_flags flags)
+static inline bool housekeeping_cpu(int cpu, enum hk_type type)
 {
 #ifdef CONFIG_CPU_ISOLATION
 	if (static_branch_unlikely(&housekeeping_overridden))
-		return housekeeping_test_cpu(cpu, flags);
+		return housekeeping_test_cpu(cpu, type);
 #endif
 	return true;
 }

kernel/cgroup/cpuset.c

···
 			update_domain_attr_tree(dattr, &top_cpuset);
 		}
 		cpumask_and(doms[0], top_cpuset.effective_cpus,
-			    housekeeping_cpumask(HK_FLAG_DOMAIN));
+			    housekeeping_cpumask(HK_TYPE_DOMAIN));
 
 		goto done;
 	}
···
 		if (!cpumask_empty(cp->cpus_allowed) &&
 		    !(is_sched_load_balance(cp) &&
 		      cpumask_intersects(cp->cpus_allowed,
-					 housekeeping_cpumask(HK_FLAG_DOMAIN))))
+					 housekeeping_cpumask(HK_TYPE_DOMAIN))))
 			continue;
 
 		if (root_load_balance &&
···
 
 			if (apn == b->pn) {
 				cpumask_or(dp, dp, b->effective_cpus);
-				cpumask_and(dp, dp, housekeeping_cpumask(HK_FLAG_DOMAIN));
+				cpumask_and(dp, dp, housekeeping_cpumask(HK_TYPE_DOMAIN));
 				if (dattr)
 					update_domain_attr_tree(dattr + nslot, b);
 

kernel/cpu.c

···
 	cpu_maps_update_begin();
 	if (primary == -1) {
 		primary = cpumask_first(cpu_online_mask);
-		if (!housekeeping_cpu(primary, HK_FLAG_TIMER))
-			primary = housekeeping_any_cpu(HK_FLAG_TIMER);
+		if (!housekeeping_cpu(primary, HK_TYPE_TIMER))
+			primary = housekeeping_any_cpu(HK_TYPE_TIMER);
 	} else {
 		if (!cpu_online(primary))
 			primary = cpumask_first(cpu_online_mask);

kernel/irq/cpuhotplug.c

···
 {
 	const struct cpumask *hk_mask;
 
-	if (!housekeeping_enabled(HK_FLAG_MANAGED_IRQ))
+	if (!housekeeping_enabled(HK_TYPE_MANAGED_IRQ))
 		return false;
 
-	hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
+	hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
 	if (cpumask_subset(irq_data_get_effective_affinity_mask(data), hk_mask))
 		return false;
 

kernel/irq/manage.c

···
 	 * online.
 	 */
 	if (irqd_affinity_is_managed(data) &&
-	    housekeeping_enabled(HK_FLAG_MANAGED_IRQ)) {
+	    housekeeping_enabled(HK_TYPE_MANAGED_IRQ)) {
 		const struct cpumask *hk_mask, *prog_mask;
 
 		static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
 		static struct cpumask tmp_mask;
 
-		hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
+		hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
 
 		raw_spin_lock(&tmp_mask_lock);
 		cpumask_and(&tmp_mask, mask, hk_mask);

kernel/kthread.c

···
 	 * back to default in case they have been changed.
 	 */
 	sched_setscheduler_nocheck(current, SCHED_NORMAL, &param);
-	set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_FLAG_KTHREAD));
+	set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_TYPE_KTHREAD));
 
 	/* OK, tell user we're spawned, wait for stop or wakeup */
 	__set_current_state(TASK_UNINTERRUPTIBLE);
···
 	/* Setup a clean context for our children to inherit. */
 	set_task_comm(tsk, "kthreadd");
 	ignore_signals(tsk);
-	set_cpus_allowed_ptr(tsk, housekeeping_cpumask(HK_FLAG_KTHREAD));
+	set_cpus_allowed_ptr(tsk, housekeeping_cpumask(HK_TYPE_KTHREAD));
 	set_mems_allowed(node_states[N_MEMORY]);
 
 	current->flags |= PF_NOFREEZE;

kernel/rcu/tasks.h

···
 	struct rcu_tasks *rtp = arg;
 
 	/* Run on housekeeping CPUs by default.  Sysadm can move if desired. */
-	housekeeping_affine(current, HK_FLAG_RCU);
+	housekeeping_affine(current, HK_TYPE_RCU);
 	WRITE_ONCE(rtp->kthread_ptr, current); // Let GPs start!
 
 	/*

kernel/rcu/tree_plugin.h

···
 		if ((mask & leaf_node_cpu_bit(rnp, cpu)) &&
 		    cpu != outgoingcpu)
 			cpumask_set_cpu(cpu, cm);
-	cpumask_and(cm, cm, housekeeping_cpumask(HK_FLAG_RCU));
+	cpumask_and(cm, cm, housekeeping_cpumask(HK_TYPE_RCU));
 	if (cpumask_weight(cm) == 0)
-		cpumask_copy(cm, housekeeping_cpumask(HK_FLAG_RCU));
+		cpumask_copy(cm, housekeeping_cpumask(HK_TYPE_RCU));
 	set_cpus_allowed_ptr(t, cm);
 	free_cpumask_var(cm);
 }
···
 {
 	if (!tick_nohz_full_enabled())
 		return;
-	housekeeping_affine(current, HK_FLAG_RCU);
+	housekeeping_affine(current, HK_TYPE_RCU);
 }
 
 /* Record the current task on dyntick-idle entry. */

kernel/sched/core.c

···
 	struct sched_domain *sd;
 	const struct cpumask *hk_mask;
 
-	if (housekeeping_cpu(cpu, HK_FLAG_TIMER)) {
+	if (housekeeping_cpu(cpu, HK_TYPE_TIMER)) {
 		if (!idle_cpu(cpu))
 			return cpu;
 		default_cpu = cpu;
 	}
 
-	hk_mask = housekeeping_cpumask(HK_FLAG_TIMER);
+	hk_mask = housekeeping_cpumask(HK_TYPE_TIMER);
 
 	rcu_read_lock();
 	for_each_domain(cpu, sd) {
···
 	}
 
 	if (default_cpu == -1)
-		default_cpu = housekeeping_any_cpu(HK_FLAG_TIMER);
+		default_cpu = housekeeping_any_cpu(HK_TYPE_TIMER);
 	cpu = default_cpu;
 unlock:
 	rcu_read_unlock();
···
 	int os;
 	struct tick_work *twork;
 
-	if (housekeeping_cpu(cpu, HK_FLAG_TICK))
+	if (housekeeping_cpu(cpu, HK_TYPE_TICK))
 		return;
 
 	WARN_ON_ONCE(!tick_work_cpu);
···
 	struct tick_work *twork;
 	int os;
 
-	if (housekeeping_cpu(cpu, HK_FLAG_TICK))
+	if (housekeeping_cpu(cpu, HK_TYPE_TICK))
 		return;
 
 	WARN_ON_ONCE(!tick_work_cpu);
···
 	mutex_unlock(&sched_domains_mutex);
 
 	/* Move init over to a non-isolated CPU */
-	if (set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_FLAG_DOMAIN)) < 0)
+	if (set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_TYPE_DOMAIN)) < 0)
 		BUG();
 	current->flags &= ~PF_NO_SETAFFINITY;
 	sched_init_granularity();

kernel/sched/fair.c

···
  * - When one of the busy CPUs notice that there may be an idle rebalancing
  *   needed, they will kick the idle load balancer, which then does idle
  *   load balancing for all the idle CPUs.
- * - HK_FLAG_MISC CPUs are used for this task, because HK_FLAG_SCHED not set
+ * - HK_TYPE_MISC CPUs are used for this task, because HK_TYPE_SCHED not set
  *   anywhere yet.
  */
 
···
 	int ilb;
 	const struct cpumask *hk_mask;
 
-	hk_mask = housekeeping_cpumask(HK_FLAG_MISC);
+	hk_mask = housekeeping_cpumask(HK_TYPE_MISC);
 
 	for_each_cpu_and(ilb, nohz.idle_cpus_mask, hk_mask) {
 
···
 
 /*
  * Kick a CPU to do the nohz balancing, if it is time for it. We pick any
- * idle CPU in the HK_FLAG_MISC housekeeping set (if there is one).
+ * idle CPU in the HK_TYPE_MISC housekeeping set (if there is one).
  */
 static void kick_ilb(unsigned int flags)
 {
···
 		return;
 
 	/* Spare idle load balancing on CPUs that don't want to be disturbed: */
-	if (!housekeeping_cpu(cpu, HK_FLAG_SCHED))
+	if (!housekeeping_cpu(cpu, HK_TYPE_SCHED))
 		return;
 
 	/*
···
 	 * This CPU doesn't want to be disturbed by scheduler
 	 * housekeeping
 	 */
-	if (!housekeeping_cpu(this_cpu, HK_FLAG_SCHED))
+	if (!housekeeping_cpu(this_cpu, HK_TYPE_SCHED))
 		return;
 
 	/* Will wake up very soon. No time for doing anything else*/

kernel/sched/isolation.c

···
  */
 #include "sched.h"
 
+enum hk_flags {
+	HK_FLAG_TIMER		= BIT(HK_TYPE_TIMER),
+	HK_FLAG_RCU		= BIT(HK_TYPE_RCU),
+	HK_FLAG_MISC		= BIT(HK_TYPE_MISC),
+	HK_FLAG_SCHED		= BIT(HK_TYPE_SCHED),
+	HK_FLAG_TICK		= BIT(HK_TYPE_TICK),
+	HK_FLAG_DOMAIN		= BIT(HK_TYPE_DOMAIN),
+	HK_FLAG_WQ		= BIT(HK_TYPE_WQ),
+	HK_FLAG_MANAGED_IRQ	= BIT(HK_TYPE_MANAGED_IRQ),
+	HK_FLAG_KTHREAD		= BIT(HK_TYPE_KTHREAD),
+};
+
 DEFINE_STATIC_KEY_FALSE(housekeeping_overridden);
 EXPORT_SYMBOL_GPL(housekeeping_overridden);
 static cpumask_var_t housekeeping_mask;
 static unsigned int housekeeping_flags;
 
-bool housekeeping_enabled(enum hk_flags flags)
+bool housekeeping_enabled(enum hk_type type)
 {
-	return !!(housekeeping_flags & flags);
+	return !!(housekeeping_flags & BIT(type));
 }
 EXPORT_SYMBOL_GPL(housekeeping_enabled);
 
-int housekeeping_any_cpu(enum hk_flags flags)
+int housekeeping_any_cpu(enum hk_type type)
 {
 	int cpu;
 
 	if (static_branch_unlikely(&housekeeping_overridden)) {
-		if (housekeeping_flags & flags) {
+		if (housekeeping_flags & BIT(type)) {
 			cpu = sched_numa_find_closest(housekeeping_mask, smp_processor_id());
 			if (cpu < nr_cpu_ids)
 				return cpu;
···
 }
 EXPORT_SYMBOL_GPL(housekeeping_any_cpu);
 
-const struct cpumask *housekeeping_cpumask(enum hk_flags flags)
+const struct cpumask *housekeeping_cpumask(enum hk_type type)
 {
 	if (static_branch_unlikely(&housekeeping_overridden))
-		if (housekeeping_flags & flags)
+		if (housekeeping_flags & BIT(type))
 			return housekeeping_mask;
 	return cpu_possible_mask;
 }
 EXPORT_SYMBOL_GPL(housekeeping_cpumask);
 
-void housekeeping_affine(struct task_struct *t, enum hk_flags flags)
+void housekeeping_affine(struct task_struct *t, enum hk_type type)
 {
 	if (static_branch_unlikely(&housekeeping_overridden))
-		if (housekeeping_flags & flags)
+		if (housekeeping_flags & BIT(type))
 			set_cpus_allowed_ptr(t, housekeeping_mask);
 }
 EXPORT_SYMBOL_GPL(housekeeping_affine);
 
-bool housekeeping_test_cpu(int cpu, enum hk_flags flags)
+bool housekeeping_test_cpu(int cpu, enum hk_type type)
 {
 	if (static_branch_unlikely(&housekeeping_overridden))
-		if (housekeeping_flags & flags)
+		if (housekeeping_flags & BIT(type))
 			return cpumask_test_cpu(cpu, housekeeping_mask);
 	return true;
 }

kernel/sched/topology.c

···
 	list_for_each_entry(entry, &asym_cap_list, link)
 		cpumask_clear(cpu_capacity_span(entry));
 
-	for_each_cpu_and(cpu, cpu_possible_mask, housekeeping_cpumask(HK_FLAG_DOMAIN))
+	for_each_cpu_and(cpu, cpu_possible_mask, housekeeping_cpumask(HK_TYPE_DOMAIN))
 		asym_cpu_capacity_update_data(cpu);
 
 	list_for_each_entry_safe(entry, next, &asym_cap_list, link) {
···
 	doms_cur = alloc_sched_domains(ndoms_cur);
 	if (!doms_cur)
 		doms_cur = &fallback_doms;
-	cpumask_and(doms_cur[0], cpu_map, housekeeping_cpumask(HK_FLAG_DOMAIN));
+	cpumask_and(doms_cur[0], cpu_map, housekeeping_cpumask(HK_TYPE_DOMAIN));
 	err = build_sched_domains(doms_cur[0], NULL);
 
 	return err;
···
 		if (doms_new) {
 			n = 1;
 			cpumask_and(doms_new[0], cpu_active_mask,
-				    housekeeping_cpumask(HK_FLAG_DOMAIN));
+				    housekeeping_cpumask(HK_TYPE_DOMAIN));
 		}
 	} else {
 		n = ndoms_new;
···
 		n = 0;
 		doms_new = &fallback_doms;
 		cpumask_and(doms_new[0], cpu_active_mask,
-			    housekeeping_cpumask(HK_FLAG_DOMAIN));
+			    housekeeping_cpumask(HK_TYPE_DOMAIN));
 	}
 
 	/* Build new domains: */

kernel/watchdog.c

···
 		pr_info("Disabling watchdog on nohz_full cores by default\n");
 
 	cpumask_copy(&watchdog_cpumask,
-		     housekeeping_cpumask(HK_FLAG_TIMER));
+		     housekeeping_cpumask(HK_TYPE_TIMER));
 
 	if (!watchdog_nmi_probe())
 		nmi_watchdog_available = true;

kernel/workqueue.c

···
 	BUILD_BUG_ON(__alignof__(struct pool_workqueue) < __alignof__(long long));
 
 	BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL));
-	cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(HK_FLAG_WQ));
-	cpumask_and(wq_unbound_cpumask, wq_unbound_cpumask, housekeeping_cpumask(HK_FLAG_DOMAIN));
+	cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(HK_TYPE_WQ));
+	cpumask_and(wq_unbound_cpumask, wq_unbound_cpumask, housekeeping_cpumask(HK_TYPE_DOMAIN));
 
 	pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC);
 

net/core/net-sysfs.c

···
 	}
 
 	if (!cpumask_empty(mask)) {
-		cpumask_and(mask, mask, housekeeping_cpumask(HK_FLAG_DOMAIN));
-		cpumask_and(mask, mask, housekeeping_cpumask(HK_FLAG_WQ));
+		cpumask_and(mask, mask, housekeeping_cpumask(HK_TYPE_DOMAIN));
+		cpumask_and(mask, mask, housekeeping_cpumask(HK_TYPE_WQ));
 		if (cpumask_empty(mask)) {
 			free_cpumask_var(mask);
 			return -EINVAL;