[PATCH 4/4] powerpc/perf: Use perf_instruction_pointer in callchains

[Anton Blanchard <anton@samba.org>]

We use SIAR or regs->nip for the instruction pointer depending on
the PMU configuration, but we always use regs->nip in the callchain.

Use perf_instruction_pointer so the backtrace is consistent.

Signed-off-by: Anton Blanchard <anton@samba.org>
---

Index: linux-build/arch/powerpc/perf/callchain.c
===================================================================
--- linux-build.orig/arch/powerpc/perf/callchain.c	2012-04-12 11:36:26.236223786 +1000
+++ linux-build/arch/powerpc/perf/callchain.c	2012-06-26 12:49:28.944202712 +1000
@@ -57,7 +57,7 @@ perf_callchain_kernel(struct perf_callch
 
 	lr = regs->link;
 	sp = regs->gpr[1];
-	perf_callchain_store(entry, regs->nip);
+	perf_callchain_store(entry, perf_instruction_pointer(regs));
 
 	if (!validate_sp(sp, current, STACK_FRAME_OVERHEAD))
 		return;
@@ -238,7 +238,7 @@ static void perf_callchain_user_64(struc
 	struct signal_frame_64 __user *sigframe;
 	unsigned long __user *fp, *uregs;
 
-	next_ip = regs->nip;
+	next_ip = perf_instruction_pointer(regs);
 	lr = regs->link;
 	sp = regs->gpr[1];
 	perf_callchain_store(entry, next_ip);
@@ -444,7 +444,7 @@ static void perf_callchain_user_32(struc
 	long level = 0;
 	unsigned int __user *fp, *uregs;
 
-	next_ip = regs->nip;
+	next_ip = perf_instruction_pointer(regs);
 	lr = regs->link;
 	sp = regs->gpr[1];
 	perf_callchain_store(entry, next_ip);