hw/intc/arm_gic: add tracepoints

These are obviously critical to understanding interrupt delivery:
gic_enable_irq
gic_disable_irq
gic_set_irq (inbound irq from device models)
gic_update_set_irq (outbound irq to CPU)
gic_acknowledge_irq

The only one that I think might raise eyebrows is gic_update_bestirq, but I've
(sadly) debugged problems that ended up being caused by unexpected priorities.
Knowing that the GIC has an irq ready, but doesn't deliver to the CPU due to
priority, has also proven important.

Signed-off-by: Hollis Blanchard <hollis_blanchard@mentor.com>
Message-id: 1461252281-22399-1-git-send-email-hollis_blanchard@mentor.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
index f55124174d..5ee79b83e6 100644
--- a/hw/intc/arm_gic.c
+++ b/hw/intc/arm_gic.c
@@ -23,6 +23,7 @@
 #include "gic_internal.h"
 #include "qapi/error.h"
 #include "qom/cpu.h"
+#include "trace.h"
 
 //#define DEBUG_GIC
 
@@ -93,6 +94,11 @@ void gic_update(GICState *s)
             }
         }
 
+        if (best_irq != 1023) {
+            trace_gic_update_bestirq(cpu, best_irq, best_prio,
+                s->priority_mask[cpu], s->running_priority[cpu]);
+        }
+
         irq_level = fiq_level = 0;
 
         if (best_prio < s->priority_mask[cpu]) {
@@ -106,10 +112,12 @@ void gic_update(GICState *s)
                         DPRINTF("Raised pending FIQ %d (cpu %d)\n",
                                 best_irq, cpu);
                         fiq_level = 1;
+                        trace_gic_update_set_irq(cpu, "fiq", fiq_level);
                     } else {
                         DPRINTF("Raised pending IRQ %d (cpu %d)\n",
                                 best_irq, cpu);
                         irq_level = 1;
+                        trace_gic_update_set_irq(cpu, "irq", irq_level);
                     }
                 }
             }
@@ -197,6 +205,7 @@ static void gic_set_irq(void *opaque, int irq, int level)
     } else {
         gic_set_irq_generic(s, irq, level, cm, target);
     }
+    trace_gic_set_irq(irq, level, cm, target);
 
     gic_update(s);
 }
@@ -332,6 +341,7 @@ uint32_t gic_acknowledge_irq(GICState *s, int cpu, MemTxAttrs attrs)
      * is in the wrong group.
      */
     irq = gic_get_current_pending_irq(s, cpu, attrs);
+    trace_gic_acknowledge_irq(cpu, irq);
 
     if (irq >= GIC_MAXIRQ) {
         DPRINTF("ACK, no pending interrupt or it is hidden: %d\n", irq);
@@ -853,6 +863,7 @@ static void gic_dist_writeb(void *opaque, hwaddr offset,
 
                 if (!GIC_TEST_ENABLED(irq + i, cm)) {
                     DPRINTF("Enabled IRQ %d\n", irq + i);
+                    trace_gic_enable_irq(irq + i);
                 }
                 GIC_SET_ENABLED(irq + i, cm);
                 /* If a raised level triggered IRQ enabled then mark
@@ -879,6 +890,7 @@ static void gic_dist_writeb(void *opaque, hwaddr offset,
 
                 if (GIC_TEST_ENABLED(irq + i, cm)) {
                     DPRINTF("Disabled IRQ %d\n", irq + i);
+                    trace_gic_disable_irq(irq + i);
                 }
                 GIC_CLEAR_ENABLED(irq + i, cm);
             }