[PATCH 0/3] IRQ trivial clarifications

These don't fix anything at all.  But they might make code understanding
and debugging slightly easier.

---

Bjorn Helgaas (3):
      x86, irq: Rename VECTOR_UNDEFINED and VECTOR_RETRIGGERED to IRQ_*
      x86, irq: Clarify "No irq handler" message
      IRQ: Print "unexpected IRQ" messages consistently across architectures


 arch/alpha/kernel/irq.c            |    2 +-
 arch/blackfin/kernel/irqchip.c     |    2 +-
 arch/c6x/kernel/irq.c              |    2 +-
 arch/ia64/kernel/irq.c             |    2 +-
 arch/m68k/include/asm/hardirq.h    |    2 +-
 arch/mips/kernel/irq.c             |    2 +-
 arch/mn10300/kernel/irq.c          |    2 +-
 arch/parisc/include/asm/hardirq.h  |    2 +-
 arch/powerpc/include/asm/hardirq.h |    2 +-
 arch/s390/include/asm/hardirq.h    |    2 +-
 arch/sh/kernel/irq.c               |    2 +-
 arch/tile/kernel/irq.c             |    2 +-
 arch/x86/include/asm/hw_irq.h      |    4 ++--
 arch/x86/kernel/apic/vector.c      |   14 +++++++-------
 arch/x86/kernel/irq.c              |   19 +++++++++----------
 arch/x86/kernel/irqinit.c          |    4 ++--
 include/asm-generic/hardirq.h      |    2 +-
 17 files changed, 33 insertions(+), 34 deletions(-)

The per-cpu vector_irq[] table is indexed by CPU vector numbers, and each
entry contains an IRQ number.

Rename the special values VECTOR_UNDEFINED and VECTOR_RETRIGGERED to
IRQ_UNDEFINED and IRQ_RETRIGGERED to indicate that they are in the IRQ
number space, not the CPU vector number space.

No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 arch/x86/include/asm/hw_irq.h |    4 ++--
 arch/x86/kernel/apic/vector.c |   14 +++++++-------
 arch/x86/kernel/irq.c         |   12 ++++++------
 arch/x86/kernel/irqinit.c     |    4 ++--
 4 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index 6615032..b51a1ca 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h

@@ -182,8 +182,8 @@ extern char irq_entries_start[];
 #define trace_irq_entries_start irq_entries_start
 #endif
 
-#define VECTOR_UNDEFINED	(-1)
-#define VECTOR_RETRIGGERED	(-2)
+#define IRQ_UNDEFINED	(-1)
+#define IRQ_RETRIGGERED	(-2)
 
 typedef int vector_irq_t[NR_VECTORS];
 DECLARE_PER_CPU(vector_irq_t, vector_irq);

diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 28eba2d..8ae84b4 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c

@@ -170,7 +170,7 @@ next:
 
 		for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask) {
 			if (per_cpu(vector_irq, new_cpu)[vector] >
-			    VECTOR_UNDEFINED)
+			    IRQ_UNDEFINED)
 				goto next;
 		}
 		/* Found one! */

@@ -232,7 +232,7 @@ static void clear_irq_vector(int irq, struct apic_chip_data *data)
 
 	vector = data->cfg.vector;
 	for_each_cpu_and(cpu, data->domain, cpu_online_mask)
-		per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
+		per_cpu(vector_irq, cpu)[vector] = IRQ_UNDEFINED;
 
 	data->cfg.vector = 0;
 	cpumask_clear(data->domain);

@@ -247,7 +247,7 @@ static void clear_irq_vector(int irq, struct apic_chip_data *data)
 		     vector++) {
 			if (per_cpu(vector_irq, cpu)[vector] != irq)
 				continue;
-			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
+			per_cpu(vector_irq, cpu)[vector] = IRQ_UNDEFINED;
 			break;
 		}
 	}

@@ -429,12 +429,12 @@ static void __setup_vector_irq(int cpu)
 	/* Mark the free vectors */
 	for (vector = 0; vector < NR_VECTORS; ++vector) {
 		irq = per_cpu(vector_irq, cpu)[vector];
-		if (irq <= VECTOR_UNDEFINED)
+		if (irq <= IRQ_UNDEFINED)
 			continue;
 
 		data = apic_chip_data(irq_get_irq_data(irq));
 		if (!cpumask_test_cpu(cpu, data->domain))
-			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
+			per_cpu(vector_irq, cpu)[vector] = IRQ_UNDEFINED;
 	}
 	raw_spin_unlock(&vector_lock);
 }

@@ -553,7 +553,7 @@ asmlinkage __visible void smp_irq_move_cleanup_interrupt(void)
 
 		irq = __this_cpu_read(vector_irq[vector]);
 
-		if (irq <= VECTOR_UNDEFINED)
+		if (irq <= IRQ_UNDEFINED)
 			continue;
 
 		desc = irq_to_desc(irq);

@@ -589,7 +589,7 @@ asmlinkage __visible void smp_irq_move_cleanup_interrupt(void)
 			apic->send_IPI_self(IRQ_MOVE_CLEANUP_VECTOR);
 			goto unlock;
 		}
-		__this_cpu_write(vector_irq[vector], VECTOR_UNDEFINED);
+		__this_cpu_write(vector_irq[vector], IRQ_UNDEFINED);
 unlock:
 		raw_spin_unlock(&desc->lock);
 	}

diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 88b36648..2949c6e 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c

@@ -223,12 +223,12 @@ __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 	if (!handle_irq(irq, regs)) {
 		ack_APIC_irq();
 
-		if (irq != VECTOR_RETRIGGERED) {
+		if (irq != IRQ_RETRIGGERED) {
 			pr_emerg_ratelimited("%s: %d.%d No irq handler for vector (irq %d)\n",
 					     __func__, smp_processor_id(),
 					     vector, irq);
 		} else {
-			__this_cpu_write(vector_irq[vector], VECTOR_UNDEFINED);
+			__this_cpu_write(vector_irq[vector], IRQ_UNDEFINED);
 		}
 	}
 

@@ -489,7 +489,7 @@ void fixup_irqs(void)
 	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
 		unsigned int irr;
 
-		if (__this_cpu_read(vector_irq[vector]) <= VECTOR_UNDEFINED)
+		if (__this_cpu_read(vector_irq[vector]) <= IRQ_UNDEFINED)
 			continue;
 
 		irr = apic_read(APIC_IRR + (vector / 32 * 0x10));

@@ -502,12 +502,12 @@ void fixup_irqs(void)
 			raw_spin_lock(&desc->lock);
 			if (chip->irq_retrigger) {
 				chip->irq_retrigger(data);
-				__this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED);
+				__this_cpu_write(vector_irq[vector], IRQ_RETRIGGERED);
 			}
 			raw_spin_unlock(&desc->lock);
 		}
-		if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED)
-			__this_cpu_write(vector_irq[vector], VECTOR_UNDEFINED);
+		if (__this_cpu_read(vector_irq[vector]) != IRQ_RETRIGGERED)
+			__this_cpu_write(vector_irq[vector], IRQ_UNDEFINED);
 	}
 }
 #endif

diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
index a3a5e15..fc1822d 100644
--- a/arch/x86/kernel/irqinit.c
+++ b/arch/x86/kernel/irqinit.c

@@ -52,7 +52,7 @@ static struct irqaction irq2 = {
 };
 
 DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
-	[0 ... NR_VECTORS - 1] = VECTOR_UNDEFINED,
+	[0 ... NR_VECTORS - 1] = IRQ_UNDEFINED,
 };
 
 int vector_used_by_percpu_irq(unsigned int vector)

@@ -60,7 +60,7 @@ int vector_used_by_percpu_irq(unsigned int vector)
 	int cpu;
 
 	for_each_online_cpu(cpu) {
-		if (per_cpu(vector_irq, cpu)[vector] > VECTOR_UNDEFINED)
+		if (per_cpu(vector_irq, cpu)[vector] > IRQ_UNDEFINED)
 			return 1;
 	}
 

Previously we printed, e.g.,

  do_IRQ: 0.242 No irq handler for vector (irq -1)

There's no clue about what "0.242" means, and the IRQ number, which is the
important generic information used by drivers and /proc/interrupts, is
almost an afterthought.

Change the format to this:

  No handler for IRQ -1 (CPU 0 vector 0xf2)

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 arch/x86/kernel/irq.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 2949c6e..3c6b069 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c

@@ -224,9 +224,8 @@ __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 		ack_APIC_irq();
 
 		if (irq != IRQ_RETRIGGERED) {
-			pr_emerg_ratelimited("%s: %d.%d No irq handler for vector (irq %d)\n",
-					     __func__, smp_processor_id(),
-					     vector, irq);
+			pr_emerg_ratelimited("No handler for IRQ %d (CPU %d vector %#x)\n",
+					     irq, smp_processor_id(), vector);
 		} else {
 			__this_cpu_write(vector_irq[vector], IRQ_UNDEFINED);
 		}

Many architectures use a variant of "unexpected IRQ trap at vector %x" to
log unexpected IRQs.  This is confusing because (a) it prints the Linux IRQ
number, but "vector" more often refers to a CPU vector number, and (b) it
prints the IRQ number in hex with no base indication, while Linux IRQ
numbers are usually printed in decimal.

Print the same text ("unexpected IRQ %d") across all architectures.

No functional change other than the output text.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 arch/alpha/kernel/irq.c            |    2 +-
 arch/blackfin/kernel/irqchip.c     |    2 +-
 arch/c6x/kernel/irq.c              |    2 +-
 arch/ia64/kernel/irq.c             |    2 +-
 arch/m68k/include/asm/hardirq.h    |    2 +-
 arch/mips/kernel/irq.c             |    2 +-
 arch/mn10300/kernel/irq.c          |    2 +-
 arch/parisc/include/asm/hardirq.h  |    2 +-
 arch/powerpc/include/asm/hardirq.h |    2 +-
 arch/s390/include/asm/hardirq.h    |    2 +-
 arch/sh/kernel/irq.c               |    2 +-
 arch/tile/kernel/irq.c             |    2 +-
 arch/x86/kernel/irq.c              |    2 +-
 include/asm-generic/hardirq.h      |    2 +-
 14 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c
index 51f2c86..9acdc14 100644
--- a/arch/alpha/kernel/irq.c
+++ b/arch/alpha/kernel/irq.c

@@ -34,7 +34,7 @@ DEFINE_PER_CPU(unsigned long, irq_pmi_count);
 void ack_bad_irq(unsigned int irq)
 {
 	irq_err_count++;
-	printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq);
+	printk(KERN_CRIT "Unexpected IRQ %d\n", irq);
 }
 
 #ifdef CONFIG_SMP 

diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c
index 0ba2576..608741e 100644
--- a/arch/blackfin/kernel/irqchip.c
+++ b/arch/blackfin/kernel/irqchip.c

@@ -20,7 +20,7 @@ static atomic_t irq_err_count;
 void ack_bad_irq(unsigned int irq)
 {
 	atomic_inc(&irq_err_count);
-	printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
+	printk(KERN_ERR "unexpected IRQ %d\n", irq);
 }
 
 static struct irq_desc bad_irq_desc = {

diff --git a/arch/c6x/kernel/irq.c b/arch/c6x/kernel/irq.c
index 247e0eb..cd7fb55 100644
--- a/arch/c6x/kernel/irq.c
+++ b/arch/c6x/kernel/irq.c

@@ -120,7 +120,7 @@ void __init init_IRQ(void)
 
 void ack_bad_irq(int irq)
 {
-	printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
+	printk(KERN_ERR "unexpected IRQ %d\n", irq);
 	irq_err_count++;
 }
 

diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c
index 812a1e6..b198c69 100644
--- a/arch/ia64/kernel/irq.c
+++ b/arch/ia64/kernel/irq.c

@@ -31,7 +31,7 @@
  */
 void ack_bad_irq(unsigned int irq)
 {
-	printk(KERN_ERR "Unexpected irq vector 0x%x on CPU %u!\n", irq, smp_processor_id());
+	printk(KERN_ERR "unexpected IRQ %d on CPU %u!\n", irq, smp_processor_id());
 }
 
 #ifdef CONFIG_IA64_GENERIC

diff --git a/arch/m68k/include/asm/hardirq.h b/arch/m68k/include/asm/hardirq.h
index 6c61852..5f0fe98 100644
--- a/arch/m68k/include/asm/hardirq.h
+++ b/arch/m68k/include/asm/hardirq.h

@@ -9,7 +9,7 @@
 
 static inline void ack_bad_irq(unsigned int irq)
 {
-	pr_crit("unexpected IRQ trap at vector %02x\n", irq);
+	pr_crit("unexpected IRQ %d\n", irq);
 }
 
 /* entry.S is sensitive to the offsets of these fields */

diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index 8eb5af8..f6b9ce9 100644
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c

@@ -31,7 +31,7 @@
  */
 void ack_bad_irq(unsigned int irq)
 {
-	printk("unexpected IRQ # %d\n", irq);
+	printk("unexpected IRQ %d\n", irq);
 }
 
 atomic_t irq_err_count;

diff --git a/arch/mn10300/kernel/irq.c b/arch/mn10300/kernel/irq.c
index 480de70..c7b780d 100644
--- a/arch/mn10300/kernel/irq.c
+++ b/arch/mn10300/kernel/irq.c

@@ -197,7 +197,7 @@ static struct irq_chip mn10300_cpu_pic_edge = {
  */
 void ack_bad_irq(int irq)
 {
-	printk(KERN_WARNING "unexpected IRQ trap at vector %02x\n", irq);
+	printk(KERN_WARNING "unexpected IRQ %d\n", irq);
 }
 
 /*

diff --git a/arch/parisc/include/asm/hardirq.h b/arch/parisc/include/asm/hardirq.h
index 9b3bd03..c093c4f 100644
--- a/arch/parisc/include/asm/hardirq.h
+++ b/arch/parisc/include/asm/hardirq.h

@@ -41,6 +41,6 @@ DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 		this_cpu_write(irq_stat.__softirq_pending, (x))
 #define or_softirq_pending(x)	this_cpu_or(irq_stat.__softirq_pending, (x))
 
-#define ack_bad_irq(irq) WARN(1, "unexpected IRQ trap at vector %02x\n", irq)
+#define ack_bad_irq(irq) WARN(1, "unexpected IRQ %d\n", irq)
 
 #endif /* _PARISC_HARDIRQ_H */

diff --git a/arch/powerpc/include/asm/hardirq.h b/arch/powerpc/include/asm/hardirq.h
index 8add8b8..aa8ebbb 100644
--- a/arch/powerpc/include/asm/hardirq.h
+++ b/arch/powerpc/include/asm/hardirq.h

@@ -30,7 +30,7 @@ DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 
 static inline void ack_bad_irq(unsigned int irq)
 {
-	printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+	printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }
 
 extern u64 arch_irq_stat_cpu(unsigned int cpu);

diff --git a/arch/s390/include/asm/hardirq.h b/arch/s390/include/asm/hardirq.h
index b7eabaa..08eeacd 100644
--- a/arch/s390/include/asm/hardirq.h
+++ b/arch/s390/include/asm/hardirq.h

@@ -20,7 +20,7 @@
 
 static inline void ack_bad_irq(unsigned int irq)
 {
-	printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+	printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }
 
 #endif /* __ASM_HARDIRQ_H */

diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
index eb10ff8..093e434 100644
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c

@@ -30,7 +30,7 @@ atomic_t irq_err_count;
 void ack_bad_irq(unsigned int irq)
 {
 	atomic_inc(&irq_err_count);
-	printk("unexpected IRQ trap at vector %02x\n", irq);
+	printk("unexpected IRQ %d\n", irq);
 }
 
 #if defined(CONFIG_PROC_FS)

diff --git a/arch/tile/kernel/irq.c b/arch/tile/kernel/irq.c
index 22044fc..c8e4f88 100644
--- a/arch/tile/kernel/irq.c
+++ b/arch/tile/kernel/irq.c

@@ -250,7 +250,7 @@ EXPORT_SYMBOL(tile_irq_activate);
 
 void ack_bad_irq(unsigned int irq)
 {
-	pr_err("unexpected IRQ trap at vector %02x\n", irq);
+	pr_err("unexpected IRQ %d\n", irq);
 }
 
 /*

diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 3c6b069..a0d46d2 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c

@@ -40,7 +40,7 @@ void (*x86_platform_ipi_callback)(void) = NULL;
 void ack_bad_irq(unsigned int irq)
 {
 	if (printk_ratelimit())
-		pr_err("unexpected IRQ trap at vector %02x\n", irq);
+		pr_err("unexpected IRQ %d\n", irq);
 
 	/*
 	 * Currently unexpected vectors happen only on SMP and APIC.

diff --git a/include/asm-generic/hardirq.h b/include/asm-generic/hardirq.h
index 04d0a97..516ff5f 100644
--- a/include/asm-generic/hardirq.h
+++ b/include/asm-generic/hardirq.h

@@ -14,7 +14,7 @@ typedef struct {
 #ifndef ack_bad_irq
 static inline void ack_bad_irq(unsigned int irq)
 {
-	printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+	printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }
 #endif
 

On Sun, 2015-12-07 at 22:02:11 UTC, Bjorn Helgaas wrote:

Many architectures use a variant of "unexpected IRQ trap at vector %x" to
log unexpected IRQs.  This is confusing because (a) it prints the Linux IRQ
number, but "vector" more often refers to a CPU vector number, and (b) it
prints the IRQ number in hex with no base indication, while Linux IRQ
numbers are usually printed in decimal.

Print the same text ("unexpected IRQ %d") across all architectures.

No functional change other than the output text.

There's already a fallback version in asm-generic, so shouldn't you instead
just delete all the versions that are identical to that?

eg. on powerpc we have:

 static inline void ack_bad_irq(unsigned int irq)
 {
-	printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+	printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }

And the generic version is:

 #ifndef ack_bad_irq
 static inline void ack_bad_irq(unsigned int irq)
 {
-	printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+	printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }
 #endif

So we can just delete the powerpc version?

cheers

On Mon, Jul 13, 2015 at 12:02 AM, Bjorn Helgaas [off-list ref] wrote:

Many architectures use a variant of "unexpected IRQ trap at vector %x" to
log unexpected IRQs.  This is confusing because (a) it prints the Linux IRQ
number, but "vector" more often refers to a CPU vector number, and (b) it
prints the IRQ number in hex with no base indication, while Linux IRQ
numbers are usually printed in decimal.

Print the same text ("unexpected IRQ %d") across all architectures.

No functional change other than the output text.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---

Thanks!

 arch/m68k/include/asm/hardirq.h    |    2 +-

For m68k:
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

And it looks like m68k can switch to the asm-generic version afterwards...

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

On Sun, Jul 12, 2015 at 10:23 PM, Michael Ellerman [off-list ref] wrote:

On Sun, 2015-12-07 at 22:02:11 UTC, Bjorn Helgaas wrote:

quoted

Many architectures use a variant of "unexpected IRQ trap at vector %x" to
log unexpected IRQs.  This is confusing because (a) it prints the Linux IRQ
number, but "vector" more often refers to a CPU vector number, and (b) it
prints the IRQ number in hex with no base indication, while Linux IRQ
numbers are usually printed in decimal.

Print the same text ("unexpected IRQ %d") across all architectures.

No functional change other than the output text.

There's already a fallback version in asm-generic, so shouldn't you instead
just delete all the versions that are identical to that?

eg. on powerpc we have:

quoted

 static inline void ack_bad_irq(unsigned int irq)
 {
-     printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+     printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }

And the generic version is:

quoted

 #ifndef ack_bad_irq
 static inline void ack_bad_irq(unsigned int irq)
 {
-     printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+     printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }
 #endif

So we can just delete the powerpc version?

Wow, I really didn't do my homework here.  Not only is there a generic
version already, but there's also print_irq_desc(), which prints way
more information than any of the ack_bad_irq() implementations.

I'll try again :)

Bjorn

On Mon, 2015-07-13 at 13:35 -0500, Bjorn Helgaas wrote:

On Sun, Jul 12, 2015 at 10:23 PM, Michael Ellerman [off-list ref] wrote:

quoted

On Sun, 2015-12-07 at 22:02:11 UTC, Bjorn Helgaas wrote:

quoted

Many architectures use a variant of "unexpected IRQ trap at vector %x" to
log unexpected IRQs.  This is confusing because (a) it prints the Linux IRQ
number, but "vector" more often refers to a CPU vector number, and (b) it
prints the IRQ number in hex with no base indication, while Linux IRQ
numbers are usually printed in decimal.

Print the same text ("unexpected IRQ %d") across all architectures.

No functional change other than the output text.

There's already a fallback version in asm-generic, so shouldn't you instead
just delete all the versions that are identical to that?

eg. on powerpc we have:

quoted

 static inline void ack_bad_irq(unsigned int irq)
 {
-     printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+     printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }

And the generic version is:

quoted

 #ifndef ack_bad_irq
 static inline void ack_bad_irq(unsigned int irq)
 {
-     printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
+     printk(KERN_CRIT "unexpected IRQ %d\n", irq);
 }
 #endif

So we can just delete the powerpc version?

Wow, I really didn't do my homework here.  Not only is there a generic
version already, but there's also print_irq_desc(), which prints way
more information than any of the ack_bad_irq() implementations.

Even better :)

I'll try again :)

Thanks.

cheers

On Sun, 12 Jul 2015, Bjorn Helgaas wrote:

The per-cpu vector_irq[] table is indexed by CPU vector numbers, and each
entry contains an IRQ number.

Rename the special values VECTOR_UNDEFINED and VECTOR_RETRIGGERED to
IRQ_UNDEFINED and IRQ_RETRIGGERED to indicate that they are in the IRQ
number space, not the CPU vector number space.

Makes some sense, but OTOH vector_irq actually reflects the vector
state not the irq number state. The fact that we store the Linux irq
number in vector_irq is just an implementation detail.

VECTOR_UNDEFINED is certainly a misnomer; that should be VECTOR_UNUSED

VECTOR_RETRIGGERED is pretty accurate. In the case we retrigger an
interrupt, we merily use the Linux irq number to figure out which
vector to kick. And after we retriggered it, we lose the association
to the Linux irq number completely.

That said, I'm working on storing the irq descriptor pointer in
vector_irq instead of the irq number, which has the advantage that we
avoid the lookup of the irq descriptor in the interrupt hotpath.

Thanks,

	tglx

On Fri, Jul 17, 2015 at 9:06 AM, Thomas Gleixner [off-list ref] wrote:

On Sun, 12 Jul 2015, Bjorn Helgaas wrote:

quoted

The per-cpu vector_irq[] table is indexed by CPU vector numbers, and each
entry contains an IRQ number.

Rename the special values VECTOR_UNDEFINED and VECTOR_RETRIGGERED to
IRQ_UNDEFINED and IRQ_RETRIGGERED to indicate that they are in the IRQ
number space, not the CPU vector number space.

Makes some sense, but OTOH vector_irq actually reflects the vector
state not the irq number state. The fact that we store the Linux irq
number in vector_irq is just an implementation detail.

VECTOR_UNDEFINED is certainly a misnomer; that should be VECTOR_UNUSED

VECTOR_RETRIGGERED is pretty accurate. In the case we retrigger an
interrupt, we merily use the Linux irq number to figure out which
vector to kick. And after we retriggered it, we lose the association
to the Linux irq number completely.

That said, I'm working on storing the irq descriptor pointer in
vector_irq instead of the irq number, which has the advantage that we
avoid the lookup of the irq descriptor in the interrupt hotpath.

OK, I'll abandon this.  Thanks for taking a look!

Bjorn