Add kernel support for oprofile callgraphs on AVR32

This patch adds backtracing capability to oprofile profiling in kernel
and user mode on AVR32. This is done by going through the frames on the
stack and adding oprofile traces for all return addresses. The code
being profiled has to be compiled with frame pointers to make this work.

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/avr32/oprofile/op_model_avr32.c b/arch/avr32/oprofile/op_model_avr32.c
index df42325c7f81..a3e9b3c4845a 100644
--- a/arch/avr32/oprofile/op_model_avr32.c
+++ b/arch/avr32/oprofile/op_model_avr32.c
@@ -22,6 +22,8 @@
 #define AVR32_PERFCTR_IRQ_GROUP 0
 #define AVR32_PERFCTR_IRQ_LINE  1
 
+void avr32_backtrace(struct pt_regs * const regs, unsigned int depth);
+
 enum { PCCNT, PCNT0, PCNT1, NR_counter };
 
 struct avr32_perf_counter {
@@ -223,6 +225,8 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
         memcpy(ops, &avr32_perf_counter_ops,
                         sizeof(struct oprofile_operations));
 
+        ops->backtrace = avr32_backtrace;
+
         printk(KERN_INFO "oprofile: using AVR32 performance monitoring.\n");
 
         return 0;