Calling irq_find_mapping from outside a irq_{enter,exit} section is
unsafe and produces ugly messages if CONFIG_PROVE_RCU is enabled:
If coming from the idle state, the rcu_read_lock call in irq_find_mapping
will generate an an unpleasant warning.
A solution is to add a new handle_domain_irq entry point into
the arm code that the interrupt controller code can call.
This new function takes an irq_domain, and calls into irq_find_domain
inside the irq_{enter,exit} block.
Interrupt controllers can then be updated to use the new mechanism.
Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
---
arch/arm/include/asm/irq.h | 2 ++
arch/arm/kernel/irq.c | 23 +++++++++++++++++++----
2 files changed, 21 insertions(+), 4 deletions(-)
diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h
index 53c15de..8578811 100644
--- a/arch/arm/include/asm/irq.h
+++ b/arch/arm/include/asm/irq.h
@@ -24,10 +24,12 @@
#ifndef __ASSEMBLY__
struct irqaction;
struct pt_regs;
+struct irq_domain;
extern void migrate_irqs(void);
extern void asm_do_IRQ(unsigned int, struct pt_regs *);
void handle_IRQ(unsigned int, struct pt_regs *);
+void handle_domain_irq(struct irq_domain *, unsigned int, struct pt_regs *);
void init_IRQ(void);
#ifdef CONFIG_MULTI_IRQ_HANDLER
diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
index 2c42576..d6af69f5 100644
--- a/arch/arm/kernel/irq.c
+++ b/arch/arm/kernel/irq.c
@@ -62,20 +62,30 @@ int arch_show_interrupts(struct seq_file *p, int prec)
* not come via this function. Instead, they should provide their
* own 'handler'. Used by platform code implementing C-based 1st
* level decoding.
+ *
+ * handle_domain_irq does the same thing, but also converts the HW
+ * interrupt number into a logical one using the provided domain. A
+ * NULL domain indicates that this conversion has already been done.
*/
-void handle_IRQ(unsigned int irq, struct pt_regs *regs)
+void handle_domain_irq(struct irq_domain *domain,
+ unsigned int hwirq, struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
+ unsigned int irq;
irq_enter();
+ if (domain)
+ irq = irq_find_mapping(domain, hwirq);
+ else
+ irq = hwirq;
+
/*
* Some hardware gives randomly wrong interrupts. Rather
* than crashing, do something sensible.
*/
- if (unlikely(irq >= nr_irqs)) {
- if (printk_ratelimit())
- printk(KERN_WARNING "Bad IRQ%u\n", irq);
+ if (unlikely(!irq || irq >= nr_irqs)) {
+ pr_warn_ratelimited("Bad IRQ%u (%u)\n", irq, hwirq);
ack_bad_irq(irq);
} else {
generic_handle_irq(irq);
@@ -85,6 +95,11 @@ void handle_IRQ(unsigned int irq, struct pt_regs *regs)
set_irq_regs(old_regs);
}
+void handle_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+ handle_domain_irq(NULL, irq, regs);
+}
+
/*
* asm_do_IRQ is the interface to be used from assembly code.
*/
--
2.0.0
--
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