From: "Frank Ch. Eigler" <f...@redhat.com>
SystemTap sdt.h sometimes results in compiled probes without sufficient
information to extract arguments. This can be solved in a slightly
hacky way by encouraging the compiler to place arguments into registers.
This patch fixes the apic_reset_irq_delivered() trace event on Fedora 20
with gcc-4.8.2-7.fc20 and systemtap-sdt-devel-2.4-2.fc20 on x86_64.
Signed-off-by: Frank Ch. Eigler <f...@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
hw/intc/apic_common.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c
index c623fcc..7ecce2d 100644
--- a/hw/intc/apic_common.c
+++ b/hw/intc/apic_common.c
@@ -117,7 +117,12 @@ void apic_report_irq_delivered(int delivered)
void apic_reset_irq_delivered(void)
{
- trace_apic_reset_irq_delivered(apic_irq_delivered);
+ /* Copy this into a local variable to encourage gcc to emit a plain
+ * register for a sys/sdt.h marker. For details on this workaround, see:
+ * https://sourceware.org/bugzilla/show_bug.cgi?id=13296
+ */
+ volatile int a_i_d = apic_irq_delivered;
+ trace_apic_reset_irq_delivered(a_i_d);
apic_irq_delivered = 0;
}
--
1.8.5.3
