diff options
author | Frank Ch. Eigler <fche@redhat.com> | 2014-03-25 13:08:30 +0100 |
---|---|---|
committer | Stefan Hajnoczi <stefanha@redhat.com> | 2014-04-01 20:08:25 +0200 |
commit | 9bcec938aab22a1b7ced916a6895e5029d4ed04f (patch) | |
tree | fc2d2e80dfc04b72cb1a512c594e8d92758d6783 | |
parent | 63678e17cf399ff81b93417fe7bee8d6ef6b6b1b (diff) |
trace: add workaround for SystemTap PR13296
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 <fche@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
-rw-r--r-- | hw/intc/apic_common.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c index c623fcc6d8..7ecce2dcce 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; } |