arm64: pass a task parameter to unwind_frame()

Function graph tracer modifies a return address (LR) in a stack frame
to hook a function's return. This will result in many useless entries
(return_to_handler) showing up in a call stack list.
We will fix this problem in a later patch ("arm64: ftrace: fix a stack
tracer's output under function graph tracer"). But since real return
addresses are saved in ret_stack[] array in struct task_struct,
unwind functions need to be notified of, in addition to a stack pointer
address, which task is being traced in order to find out real return
addresses.

This patch extends unwind functions' interfaces by adding an extra
argument of a pointer to task_struct.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c
index 13339b6ffc1a..6e5c521f123a 100644
--- a/arch/arm64/kernel/time.c
+++ b/arch/arm64/kernel/time.c
@@ -53,7 +53,7 @@ unsigned long profile_pc(struct pt_regs *regs)
 	frame.sp = regs->sp;
 	frame.pc = regs->pc;
 	do {
-		int ret = unwind_frame(&frame);
+		int ret = unwind_frame(NULL, &frame);
 		if (ret < 0)
 			return 0;
 	} while (in_lock_functions(frame.pc));