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authorLinus Torvalds <torvalds@linux-foundation.org>2020-12-24 13:50:23 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-12-24 13:50:23 -0800
commit3913d00ac51a9d93225eeea776026326ff8f717d (patch)
tree0f3ff4ceb46e7b3987866ed7d21e645d411e6ab6 /kernel/irq
parent4a1106afeed26012de69f4837b8d7a8b83f28489 (diff)
parent64a1b95bb9fe3ec76e1a2cd803eff06389341ae4 (diff)
downloadlinux-stericsson-3913d00ac51a9d93225eeea776026326ff8f717d.tar.gz
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() ...
Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/irqdesc.c45
-rw-r--r--kernel/irq/manage.c37
-rw-r--r--kernel/irq/proc.c5
3 files changed, 67 insertions, 20 deletions
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index e810eb9906ea..3d0bc38a0bcf 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -147,12 +147,12 @@ 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);
- int cpu, irq = desc->irq_data.irq;
ssize_t ret = 0;
char *p = "";
+ int cpu;
for_each_possible_cpu(cpu) {
- unsigned int c = kstat_irqs_cpu(irq, cpu);
+ unsigned int c = irq_desc_kstat_cpu(desc, cpu);
ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
p = ",";
@@ -352,7 +352,9 @@ struct irq_desc *irq_to_desc(unsigned int irq)
{
return radix_tree_lookup(&irq_desc_tree, irq);
}
-EXPORT_SYMBOL(irq_to_desc);
+#ifdef CONFIG_KVM_BOOK3S_64_HV
+EXPORT_SYMBOL_GPL(irq_to_desc);
+#endif
static void delete_irq_desc(unsigned int irq)
{
@@ -924,15 +926,7 @@ static bool irq_is_nmi(struct irq_desc *desc)
return desc->istate & IRQS_NMI;
}
-/**
- * kstat_irqs - Get the statistics for an interrupt
- * @irq: The interrupt number
- *
- * Returns the sum of interrupt counts on all cpus since boot for
- * @irq. The caller must ensure that the interrupt is not removed
- * concurrently.
- */
-unsigned int kstat_irqs(unsigned int irq)
+static unsigned int kstat_irqs(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
unsigned int sum = 0;
@@ -943,21 +937,22 @@ unsigned int kstat_irqs(unsigned int irq)
if (!irq_settings_is_per_cpu_devid(desc) &&
!irq_settings_is_per_cpu(desc) &&
!irq_is_nmi(desc))
- return desc->tot_count;
+ return data_race(desc->tot_count);
for_each_possible_cpu(cpu)
- sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
+ sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
return sum;
}
/**
- * kstat_irqs_usr - Get the statistics for an interrupt
+ * kstat_irqs_usr - Get the statistics for an interrupt from thread context
* @irq: The interrupt number
*
* Returns the sum of interrupt counts on all cpus since boot for @irq.
- * Contrary to kstat_irqs() this can be called from any context.
- * It uses rcu since a concurrent removal of an interrupt descriptor is
- * observing an rcu grace period before delayed_free_desc()/irq_kobj_release().
+ *
+ * It uses rcu to protect the access since a concurrent removal of an
+ * interrupt descriptor is observing an rcu grace period before
+ * delayed_free_desc()/irq_kobj_release().
*/
unsigned int kstat_irqs_usr(unsigned int irq)
{
@@ -968,3 +963,17 @@ unsigned int kstat_irqs_usr(unsigned int irq)
rcu_read_unlock();
return sum;
}
+
+#ifdef CONFIG_LOCKDEP
+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);
+ }
+}
+EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
+#endif
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index c826ba4141fe..ab8567f32501 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -2822,3 +2822,40 @@ out_unlock:
return err;
}
EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
+
+/**
+ * irq_has_action - Check whether an interrupt is requested
+ * @irq: The linux irq number
+ *
+ * Returns: A snapshot of the current state
+ */
+bool irq_has_action(unsigned int irq)
+{
+ bool res;
+
+ rcu_read_lock();
+ res = irq_desc_has_action(irq_to_desc(irq));
+ rcu_read_unlock();
+ return res;
+}
+EXPORT_SYMBOL_GPL(irq_has_action);
+
+/**
+ * irq_check_status_bit - Check whether bits in the irq descriptor status are set
+ * @irq: The linux irq number
+ * @bitmask: The bitmask to evaluate
+ *
+ * Returns: True if one of the bits in @bitmask is set
+ */
+bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)
+{
+ struct irq_desc *desc;
+ bool res = false;
+
+ rcu_read_lock();
+ desc = irq_to_desc(irq);
+ if (desc)
+ res = !!(desc->status_use_accessors & bitmask);
+ rcu_read_unlock();
+ return res;
+}
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 72513ed2a5fc..98138788cb04 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -488,9 +488,10 @@ int show_interrupts(struct seq_file *p, void *v)
if (!desc || irq_settings_is_hidden(desc))
goto outsparse;
- if (desc->kstat_irqs)
+ if (desc->kstat_irqs) {
for_each_online_cpu(j)
- any_count |= *per_cpu_ptr(desc->kstat_irqs, j);
+ any_count |= data_race(*per_cpu_ptr(desc->kstat_irqs, j));
+ }
if ((!desc->action || irq_desc_is_chained(desc)) && !any_count)
goto outsparse;