[PATCH 19/22] i8259: move InterruptStatsProviderClass get_statistics() from i8259 to PIC

[Mark Cave-Ayland <mark.caveayland@xxxxxxxxxxx>]

The internal i8259 implementation has workaround logic for storing interrupt
statistics since these are currently recorded at the PIC level (i.e. for all
16 interrupt lines) whilst being stored in the master i8259 device which only
has 8 physical interrupt lines.

Move the get_statistics() implementation from the individual i8259 device to
the containing PIC device in preparation for removing this hack. Note that
this has a visible change to the "info pic" HMP monitor output since the named
device displayed by "info irq" is now the PIC and not the individual i8259:

Before (TCG):

(qemu) info irq
IRQ statistics for ioapic:
 0: 68
 4: 1
IRQ statistics for isa-i8259:
 0: 68
 4: 1

After (TCG):

(qemu) info irq
IRQ statistics for ioapic:
 0: 47
 4: 1
IRQ statistics for isa-i8259-pic:
 0: 47
 4: 1

Before (KVM):

(qemu) info irq
IRQ statistics for kvm-ioapic:
 4: 1
IRQ statistics for kvm-i8259:
 4: 1

After (KVM):

(qemu) info irq
IRQ statistics for kvm-ioapic:
 1: 3
 4: 1
IRQ statistics for kvm-i8259-pic:
 1: 3
 4: 1

Signed-off-by: Mark Cave-Ayland <mark.caveayland@xxxxxxxxxxx>
---
 include/hw/intc/i8259.h         |  6 ++++++
 include/hw/isa/i8259_internal.h |  1 -
 hw/i386/kvm/i8259.c             |  7 +++++++
 hw/intc/i8259.c                 |  7 +++++++
 hw/intc/i8259_common.c          | 27 ++++++++++++++++++---------
 5 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/include/hw/intc/i8259.h b/include/hw/intc/i8259.h
index 1921a30371..24237a4ed5 100644
--- a/include/hw/intc/i8259.h
+++ b/include/hw/intc/i8259.h
@@ -1,6 +1,8 @@
 #ifndef HW_I8259_H
 #define HW_I8259_H
 
+#include "hw/intc/intc.h"
+
 /* i8259.c */
 
 typedef struct I8259CommonState I8259CommonState;
@@ -18,5 +20,9 @@ qemu_irq *i8259_init(ISABus *bus, qemu_irq parent_irq_in);
 qemu_irq *kvm_i8259_init(ISABus *bus);
 int pic_get_output(I8259CommonState *s);
 int pic_read_irq(I8259CommonState *s);
+bool i8259_pic_get_statistics(InterruptStatsProvider *obj,
+                              uint64_t **irq_counts,
+                              unsigned int *nb_irqs);
+void i8259_pic_print_info(InterruptStatsProvider *obj, GString *buf);
 
 #endif
diff --git a/include/hw/isa/i8259_internal.h b/include/hw/isa/i8259_internal.h
index 390a373511..53751b045b 100644
--- a/include/hw/isa/i8259_internal.h
+++ b/include/hw/isa/i8259_internal.h
@@ -26,7 +26,6 @@
 #define QEMU_I8259_INTERNAL_H
 
 #include "hw/isa/isa.h"
-#include "hw/intc/intc.h"
 #include "hw/intc/i8259.h"
 #include "qom/object.h"
 
diff --git a/hw/i386/kvm/i8259.c b/hw/i386/kvm/i8259.c
index 0ae5caa655..421c9279cd 100644
--- a/hw/i386/kvm/i8259.c
+++ b/hw/i386/kvm/i8259.c
@@ -206,9 +206,12 @@ static const Property kvm_i8259_pic_properties[] = {
 static void kvm_i8259_pic_class_init(ObjectClass *klass, const void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    InterruptStatsProviderClass *ic = INTERRUPT_STATS_PROVIDER_CLASS(klass);
 
     dc->realize = kvm_i8259_pic_realize;
     device_class_set_props(dc, kvm_i8259_pic_properties);
+    ic->get_statistics = i8259_pic_get_statistics;
+    ic->print_info = i8259_pic_print_info;
     /*
      * Reason: must be wired to the ISA bus via the "bus" property
      */
@@ -227,6 +230,10 @@ static const TypeInfo kvm_i8259_type_infos[] = {
         .class_init = kvm_i8259_pic_class_init,
         .instance_init = kvm_i8259_pic_init,
         .instance_size = sizeof(KVMI8259PICState),
+        .interfaces = (const InterfaceInfo[]) {
+            { TYPE_INTERRUPT_STATS_PROVIDER },
+            { }
+        },
     },
 };
 
diff --git a/hw/intc/i8259.c b/hw/intc/i8259.c
index 964ceb04b2..ffd09f6c61 100644
--- a/hw/intc/i8259.c
+++ b/hw/intc/i8259.c
@@ -517,9 +517,12 @@ static const Property i8259_pic_properties[] = {
 static void i8259_pic_class_init(ObjectClass *klass, const void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    InterruptStatsProviderClass *ic = INTERRUPT_STATS_PROVIDER_CLASS(klass);
 
     dc->realize = i8259_pic_realize;
     device_class_set_props(dc, i8259_pic_properties);
+    ic->get_statistics = i8259_pic_get_statistics;
+    ic->print_info = i8259_pic_print_info;
     /*
      * Reason: must be wired to the ISA bus via the "bus" property
      */
@@ -538,6 +541,10 @@ static const TypeInfo i8259_type_infos[] = {
         .class_init    = i8259_pic_class_init,
         .instance_init = i8259_pic_init,
         .instance_size = sizeof(I8259PICState),
+        .interfaces = (const InterfaceInfo[]) {
+            { TYPE_INTERRUPT_STATS_PROVIDER },
+            { }
+        },
     },
 };
 
diff --git a/hw/intc/i8259_common.c b/hw/intc/i8259_common.c
index b3f2600523..7980f86f1f 100644
--- a/hw/intc/i8259_common.c
+++ b/hw/intc/i8259_common.c
@@ -99,19 +99,28 @@ void i8259_stat_update_irq(int irq, int level)
     }
 }
 
+bool i8259_pic_get_statistics(InterruptStatsProvider *obj,
+                              uint64_t **irq_counts,
+                              unsigned int *nb_irqs)
+{
+    *irq_counts = irq_count;
+    *nb_irqs = ARRAY_SIZE(irq_count);
+
+    return true;
+}
+
+void i8259_pic_print_info(InterruptStatsProvider *obj, GString *buf)
+{
+    /* No information for i8259-based PICs */
+    return;
+}
+
 static bool i8259_common_get_statistics(InterruptStatsProvider *obj,
                                         uint64_t **irq_counts,
                                         unsigned int *nb_irqs)
 {
-    I8259CommonState *s = I8259_COMMON(obj);
-
-    if (s->master) {
-        *irq_counts = irq_count;
-        *nb_irqs = ARRAY_SIZE(irq_count);
-    } else {
-        *irq_counts = NULL;
-        *nb_irqs = 0;
-    }
+    /* No statistics for individual i8259s */
+    *nb_irqs = 0;
 
     return true;
 }
-- 
2.43.0