Merge tag 'irq-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq core updates from Thomas Gleixner:
 "Updates for the generic interrupt subsystem core code:

   - Address a long standing subtle problem in the CPU hotplug code for
     affinity-managed interrupts.

     Affinity-managed interrupts are shut down by the core code when the
     last CPU in the affinity set goes offline and started up again when
     the first CPU in the affinity set becomes online again.

     This unfortunately does not take into account whether an interrupt
     has been disabled before the last CPU goes offline and starts up
     the interrupt unconditionally when the first CPU becomes online
     again.

     That's obviously not what drivers expect.

     Address this by preserving the disabled state for affinity-managed
     interrupts accross these CPU hotplug operations. All non-managed
     interrupts are not affected by this because startup/shutdown is
     coupled to request/free_irq() which obviously has to reset state.

   - Support three-cell scheme interrupts to allow GPIO drivers to
     specify interrupts from an already existing scheme

   - Switch the interrupt subsystem core to lock guards. This gets rid
     of quite some copy & pasta boilerplate code all over the place.

   - The usual small cleanups and improvements all over the place"

* tag 'irq-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (59 commits)
  genirq/irqdesc: Remove double locking in hwirq_show()
  genirq: Retain disable depth for managed interrupts across CPU hotplug
  genirq: Bump the size of the local variable for sprintf()
  genirq/manage: Use the correct lock guard in irq_set_irq_wake()
  genirq: Consistently use '%u' format specifier for unsigned int variables
  genirq: Ensure flags in lock guard is consistently initialized
  genirq: Fix inverted condition in handle_nested_irq()
  genirq/cpuhotplug: Fix up lock guards conversion brainf..t
  genirq: Use scoped_guard() to shut clang up
  genirq: Remove unused remove_percpu_irq()
  genirq: Remove irq_[get|put]_desc*()
  genirq/manage: Rework irq_set_irqchip_state()
  genirq/manage: Rework irq_get_irqchip_state()
  genirq/manage: Rework teardown_percpu_nmi()
  genirq/manage: Rework prepare_percpu_nmi()
  genirq/manage: Rework disable_percpu_irq()
  genirq/manage: Rework irq_percpu_is_enabled()
  genirq/manage: Rework enable_percpu_irq()
  genirq/manage: Rework irq_set_parent()
  genirq/manage: Rework can_request_irq()
  ...

1 files changed, 65 insertions, 111 deletions

diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 4258cd6bd3b4..b64c57b44c20 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -246,8 +246,7 @@ static struct kobject *irq_kobj_base;
 #define IRQ_ATTR_RO(_name) \
 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 
-static ssize_t per_cpu_count_show(struct kobject *kobj,
-				  struct kobj_attribute *attr, char *buf)
+static ssize_t per_cpu_count_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 	ssize_t ret = 0;
@@ -257,112 +256,83 @@ static ssize_t per_cpu_count_show(struct kobject *kobj,
 	for_each_possible_cpu(cpu) {
 		unsigned int c = irq_desc_kstat_cpu(desc, cpu);
 
-		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
+		ret += sysfs_emit_at(buf, ret, "%s%u", p, c);
 		p = ",";
 	}
 
-	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
+	ret += sysfs_emit_at(buf, ret, "\n");
 	return ret;
 }
 IRQ_ATTR_RO(per_cpu_count);
 
-static ssize_t chip_name_show(struct kobject *kobj,
-			      struct kobj_attribute *attr, char *buf)
+static ssize_t chip_name_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
-	ssize_t ret = 0;
-
-	raw_spin_lock_irq(&desc->lock);
-	if (desc->irq_data.chip && desc->irq_data.chip->name) {
-		ret = scnprintf(buf, PAGE_SIZE, "%s\n",
-				desc->irq_data.chip->name);
-	}
-	raw_spin_unlock_irq(&desc->lock);
 
-	return ret;
+	guard(raw_spinlock_irq)(&desc->lock);
+	if (desc->irq_data.chip && desc->irq_data.chip->name)
+		return sysfs_emit(buf, "%s\n", desc->irq_data.chip->name);
+	return 0;
 }
 IRQ_ATTR_RO(chip_name);
 
-static ssize_t hwirq_show(struct kobject *kobj,
-			  struct kobj_attribute *attr, char *buf)
+static ssize_t hwirq_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
-	ssize_t ret = 0;
 
-	raw_spin_lock_irq(&desc->lock);
+	guard(raw_spinlock_irq)(&desc->lock);
 	if (desc->irq_data.domain)
-		ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
-	raw_spin_unlock_irq(&desc->lock);
-
-	return ret;
+		return sysfs_emit(buf, "%lu\n", desc->irq_data.hwirq);
+	return 0;
 }
 IRQ_ATTR_RO(hwirq);
 
-static ssize_t type_show(struct kobject *kobj,
-			 struct kobj_attribute *attr, char *buf)
+static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
-	ssize_t ret = 0;
 
-	raw_spin_lock_irq(&desc->lock);
-	ret = sprintf(buf, "%s\n",
-		      irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
-	raw_spin_unlock_irq(&desc->lock);
-
-	return ret;
+	guard(raw_spinlock_irq)(&desc->lock);
+	return sysfs_emit(buf, "%s\n", irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
 
 }
 IRQ_ATTR_RO(type);
 
-static ssize_t wakeup_show(struct kobject *kobj,
-			   struct kobj_attribute *attr, char *buf)
+static ssize_t wakeup_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
-	ssize_t ret = 0;
-
-	raw_spin_lock_irq(&desc->lock);
-	ret = sprintf(buf, "%s\n", str_enabled_disabled(irqd_is_wakeup_set(&desc->irq_data)));
-	raw_spin_unlock_irq(&desc->lock);
-
-	return ret;
 
+	guard(raw_spinlock_irq)(&desc->lock);
+	return sysfs_emit(buf, "%s\n", str_enabled_disabled(irqd_is_wakeup_set(&desc->irq_data)));
 }
 IRQ_ATTR_RO(wakeup);
 
-static ssize_t name_show(struct kobject *kobj,
-			 struct kobj_attribute *attr, char *buf)
+static ssize_t name_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
-	ssize_t ret = 0;
 
-	raw_spin_lock_irq(&desc->lock);
+	guard(raw_spinlock_irq)(&desc->lock);
 	if (desc->name)
-		ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
-	raw_spin_unlock_irq(&desc->lock);
-
-	return ret;
+		return sysfs_emit(buf, "%s\n", desc->name);
+	return 0;
 }
 IRQ_ATTR_RO(name);
 
-static ssize_t actions_show(struct kobject *kobj,
-			    struct kobj_attribute *attr, char *buf)
+static ssize_t actions_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 	struct irqaction *action;
 	ssize_t ret = 0;
 	char *p = "";
 
-	raw_spin_lock_irq(&desc->lock);
-	for_each_action_of_desc(desc, action) {
-		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
-				 p, action->name);
-		p = ",";
+	scoped_guard(raw_spinlock_irq, &desc->lock) {
+		for_each_action_of_desc(desc, action) {
+			ret += sysfs_emit_at(buf, ret, "%s%s", p, action->name);
+			p = ",";
+		}
 	}
-	raw_spin_unlock_irq(&desc->lock);
 
 	if (ret)
-		ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
-
+		ret += sysfs_emit_at(buf, ret, "\n");
 	return ret;
 }
 IRQ_ATTR_RO(actions);
@@ -418,19 +388,14 @@ static int __init irq_sysfs_init(void)
 	int irq;
 
 	/* Prevent concurrent irq alloc/free */
-	irq_lock_sparse();
-
+	guard(mutex)(&sparse_irq_lock);
 	irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
-	if (!irq_kobj_base) {
-		irq_unlock_sparse();
+	if (!irq_kobj_base)
 		return -ENOMEM;
-	}
 
 	/* Add the already allocated interrupts */
 	for_each_irq_desc(irq, desc)
 		irq_sysfs_add(irq, desc);
-	irq_unlock_sparse();
-
 	return 0;
 }
 postcore_initcall(irq_sysfs_init);
@@ -573,12 +538,12 @@ err:
 	return -ENOMEM;
 }
 
-static int irq_expand_nr_irqs(unsigned int nr)
+static bool irq_expand_nr_irqs(unsigned int nr)
 {
 	if (nr > MAX_SPARSE_IRQS)
-		return -ENOMEM;
+		return false;
 	nr_irqs = nr;
-	return 0;
+	return true;
 }
 
 int __init early_irq_init(void)
@@ -656,11 +621,9 @@ EXPORT_SYMBOL(irq_to_desc);
 static void free_desc(unsigned int irq)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
-	unsigned long flags;
 
-	raw_spin_lock_irqsave(&desc->lock, flags);
-	desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
-	raw_spin_unlock_irqrestore(&desc->lock, flags);
+	scoped_guard(raw_spinlock_irqsave, &desc->lock)
+		desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
 	delete_irq_desc(irq);
 }
 
@@ -679,16 +642,15 @@ static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 	return start;
 }
 
-static int irq_expand_nr_irqs(unsigned int nr)
+static inline bool irq_expand_nr_irqs(unsigned int nr)
 {
-	return -ENOMEM;
+	return false;
 }
 
 void irq_mark_irq(unsigned int irq)
 {
-	mutex_lock(&sparse_irq_lock);
+	guard(mutex)(&sparse_irq_lock);
 	irq_insert_desc(irq, irq_desc + irq);
-	mutex_unlock(&sparse_irq_lock);
 }
 
 #ifdef CONFIG_GENERIC_IRQ_LEGACY
@@ -827,11 +789,9 @@ void irq_free_descs(unsigned int from, unsigned int cnt)
 	if (from >= nr_irqs || (from + cnt) > nr_irqs)
 		return;
 
-	mutex_lock(&sparse_irq_lock);
+	guard(mutex)(&sparse_irq_lock);
 	for (i = 0; i < cnt; i++)
 		free_desc(from + i);
-
-	mutex_unlock(&sparse_irq_lock);
 }
 EXPORT_SYMBOL_GPL(irq_free_descs);
 
@@ -848,11 +808,10 @@ EXPORT_SYMBOL_GPL(irq_free_descs);
  *
  * Returns the first irq number or error code
  */
-int __ref
-__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
-		  struct module *owner, const struct irq_affinity_desc *affinity)
+int __ref __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
+			    struct module *owner, const struct irq_affinity_desc *affinity)
 {
-	int start, ret;
+	int start;
 
 	if (!cnt)
 		return -EINVAL;
@@ -870,22 +829,17 @@ __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 		from = arch_dynirq_lower_bound(from);
 	}
 
-	mutex_lock(&sparse_irq_lock);
+	guard(mutex)(&sparse_irq_lock);
 
 	start = irq_find_free_area(from, cnt);
-	ret = -EEXIST;
 	if (irq >=0 && start != irq)
-		goto unlock;
+		return -EEXIST;
 
 	if (start + cnt > nr_irqs) {
-		ret = irq_expand_nr_irqs(start + cnt);
-		if (ret)
-			goto unlock;
+		if (!irq_expand_nr_irqs(start + cnt))
+			return -ENOMEM;
 	}
-	ret = alloc_descs(start, cnt, node, affinity, owner);
-unlock:
-	mutex_unlock(&sparse_irq_lock);
-	return ret;
+	return alloc_descs(start, cnt, node, affinity, owner);
 }
 EXPORT_SYMBOL_GPL(__irq_alloc_descs);
 
@@ -900,27 +854,27 @@ unsigned int irq_get_next_irq(unsigned int offset)
 	return irq_find_at_or_after(offset);
 }
 
-struct irq_desc *
-__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
-		    unsigned int check)
+struct irq_desc *__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
+				     unsigned int check)
 {
-	struct irq_desc *desc = irq_to_desc(irq);
+	struct irq_desc *desc;
 
-	if (desc) {
-		if (check & _IRQ_DESC_CHECK) {
-			if ((check & _IRQ_DESC_PERCPU) &&
-			    !irq_settings_is_per_cpu_devid(desc))
-				return NULL;
-
-			if (!(check & _IRQ_DESC_PERCPU) &&
-			    irq_settings_is_per_cpu_devid(desc))
-				return NULL;
-		}
+	desc = irq_to_desc(irq);
+	if (!desc)
+		return NULL;
+
+	if (check & _IRQ_DESC_CHECK) {
+		if ((check & _IRQ_DESC_PERCPU) && !irq_settings_is_per_cpu_devid(desc))
+			return NULL;
 
-		if (bus)
-			chip_bus_lock(desc);
-		raw_spin_lock_irqsave(&desc->lock, *flags);
+		if (!(check & _IRQ_DESC_PERCPU) && irq_settings_is_per_cpu_devid(desc))
+			return NULL;
 	}
+
+	if (bus)
+		chip_bus_lock(desc);
+	raw_spin_lock_irqsave(&desc->lock, *flags);
+
 	return desc;
 }