[PATCH v9 02/11] arm64: Make perf_callchain_kernel() use arch_stack_walk()

[madvenka]

From: "Madhavan T. Venkataraman" <madvenka@xxxxxxxxxxxxxxxxxxx>

Currently, perf_callchain_kernel() in ARM64 code walks the stack using
start_backtrace() and walk_stackframe(). Make it use arch_stack_walk()
instead. This makes maintenance easier.

Signed-off-by: Madhavan T. Venkataraman <madvenka@xxxxxxxxxxxxxxxxxxx>
---
 arch/arm64/kernel/perf_callchain.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/kernel/perf_callchain.c b/arch/arm64/kernel/perf_callchain.c
index 4a72c2727309..f173c448e852 100644
--- a/arch/arm64/kernel/perf_callchain.c
+++ b/arch/arm64/kernel/perf_callchain.c
@@ -140,22 +140,18 @@ void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
 static bool callchain_trace(void *data, unsigned long pc)
 {
 	struct perf_callchain_entry_ctx *entry = data;
-	perf_callchain_store(entry, pc);
-	return true;
+	return perf_callchain_store(entry, pc) == 0;
 }
 
 void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
 			   struct pt_regs *regs)
 {
-	struct stackframe frame;
-
 	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
 		/* We don't support guest os callchain now */
 		return;
 	}
 
-	start_backtrace(&frame, regs->regs[29], regs->pc);
-	walk_stackframe(current, &frame, callchain_trace, entry);
+	arch_stack_walk(callchain_trace, entry, current, regs);
 }
 
 unsigned long perf_instruction_pointer(struct pt_regs *regs)
-- 
2.25.1