Merge tag 'irq-core-2020-12-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "This is the second attempt after the first one failed miserably and
  got zapped to unblock the rest of the interrupt related patches.

  A treewide cleanup of interrupt descriptor (ab)use with all sorts of
  racy accesses, inefficient and disfunctional code. The goal is to
  remove the export of irq_to_desc() to prevent these things from
  creeping up again"

* tag 'irq-core-2020-12-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  genirq: Restrict export of irq_to_desc()
  xen/events: Implement irq distribution
  xen/events: Reduce irq_info:: Spurious_cnt storage size
  xen/events: Only force affinity mask for percpu interrupts
  xen/events: Use immediate affinity setting
  xen/events: Remove disfunct affinity spreading
  xen/events: Remove unused bind_evtchn_to_irq_lateeoi()
  net/mlx5: Use effective interrupt affinity
  net/mlx5: Replace irq_to_desc() abuse
  net/mlx4: Use effective interrupt affinity
  net/mlx4: Replace irq_to_desc() abuse
  PCI: mobiveil: Use irq_data_get_irq_chip_data()
  PCI: xilinx-nwl: Use irq_data_get_irq_chip_data()
  NTB/msi: Use irq_has_action()
  mfd: ab8500-debugfs: Remove the racy fiddling with irq_desc
  pinctrl: nomadik: Use irq_has_action()
  drm/i915/pmu: Replace open coded kstat_irqs() copy
  drm/i915/lpe_audio: Remove pointless irq_to_desc() usage
  s390/irq: Use irq_desc_kstat_cpu() in show_msi_interrupt()
  parisc/irq: Use irq_desc_kstat_cpu() in show_interrupts()
  ...

4 files changed, 24 insertions, 25 deletions

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 870b3251e174..bb8ff9083e7d 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -232,6 +232,7 @@ extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
 # define local_irq_enable_in_hardirq()	local_irq_enable()
 #endif
 
+bool irq_has_action(unsigned int irq);
 extern void disable_irq_nosync(unsigned int irq);
 extern bool disable_hardirq(unsigned int irq);
 extern void disable_irq(unsigned int irq);
diff --git a/include/linux/irq.h b/include/linux/irq.h
index c332871d59da..4aeb1c4c7e07 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -906,6 +906,13 @@ struct cpumask *irq_data_get_effective_affinity_mask(struct irq_data *d)
 }
 #endif
 
+static inline struct cpumask *irq_get_effective_affinity_mask(unsigned int irq)
+{
+	struct irq_data *d = irq_get_irq_data(irq);
+
+	return d ? irq_data_get_effective_affinity_mask(d) : NULL;
+}
+
 unsigned int arch_dynirq_lower_bound(unsigned int from);
 
 int __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index 5745491303e0..891b323266df 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -113,6 +113,12 @@ static inline void irq_unlock_sparse(void) { }
 extern struct irq_desc irq_desc[NR_IRQS];
 #endif
 
+static inline unsigned int irq_desc_kstat_cpu(struct irq_desc *desc,
+					      unsigned int cpu)
+{
+	return desc->kstat_irqs ? *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
+}
+
 static inline struct irq_desc *irq_data_to_desc(struct irq_data *data)
 {
 	return container_of(data->common, struct irq_desc, irq_common_data);
@@ -179,12 +185,7 @@ int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq,
 /* Test to see if a driver has successfully requested an irq */
 static inline int irq_desc_has_action(struct irq_desc *desc)
 {
-	return desc->action != NULL;
-}
-
-static inline int irq_has_action(unsigned int irq)
-{
-	return irq_desc_has_action(irq_to_desc(irq));
+	return desc && desc->action != NULL;
 }
 
 /**
@@ -228,40 +229,31 @@ irq_set_chip_handler_name_locked(struct irq_data *data, struct irq_chip *chip,
 	data->chip = chip;
 }
 
+bool irq_check_status_bit(unsigned int irq, unsigned int bitmask);
+
 static inline bool irq_balancing_disabled(unsigned int irq)
 {
-	struct irq_desc *desc;
-
-	desc = irq_to_desc(irq);
-	return desc->status_use_accessors & IRQ_NO_BALANCING_MASK;
+	return irq_check_status_bit(irq, IRQ_NO_BALANCING_MASK);
 }
 
 static inline bool irq_is_percpu(unsigned int irq)
 {
-	struct irq_desc *desc;
-
-	desc = irq_to_desc(irq);
-	return desc->status_use_accessors & IRQ_PER_CPU;
+	return irq_check_status_bit(irq, IRQ_PER_CPU);
 }
 
 static inline bool irq_is_percpu_devid(unsigned int irq)
 {
-	struct irq_desc *desc;
-
-	desc = irq_to_desc(irq);
-	return desc->status_use_accessors & IRQ_PER_CPU_DEVID;
+	return irq_check_status_bit(irq, IRQ_PER_CPU_DEVID);
 }
 
+void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
+			     struct lock_class_key *request_class);
 static inline void
 irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
 		      struct lock_class_key *request_class)
 {
-	struct irq_desc *desc = irq_to_desc(irq);
-
-	if (desc) {
-		lockdep_set_class(&desc->lock, lock_class);
-		lockdep_set_class(&desc->request_mutex, request_class);
-	}
+	if (IS_ENABLED(CONFIG_LOCKDEP))
+		__irq_set_lockdep_class(irq, lock_class, request_class);
 }
 
 #endif
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h
index 89f0745c096d..44ae1a7eb9e3 100644
--- a/include/linux/kernel_stat.h
+++ b/include/linux/kernel_stat.h
@@ -67,7 +67,6 @@ static inline unsigned int kstat_softirqs_cpu(unsigned int irq, int cpu)
 /*
  * Number of interrupts per specific IRQ source, since bootup
  */
-extern unsigned int kstat_irqs(unsigned int irq);
 extern unsigned int kstat_irqs_usr(unsigned int irq);
 
 /*