[PATCH v2 1/3] s390/unwind: drop unnecessary code around calling ftrace_graph_ret_addr()

From: Miroslav Benes
Date: Tue Oct 29 2019 - 10:39:09 EST


The current code around calling ftrace_graph_ret_addr() is ifdeffed and
also tests if ftrace redirection is present on stack.
ftrace_graph_ret_addr() however performs the test internally and there
is a version for !CONFIG_FUNCTION_GRAPH_TRACER as well. The unnecessary
code can thus be dropped.

Signed-off-by: Miroslav Benes <mbenes@xxxxxxx>
---
arch/s390/kernel/unwind_bc.c | 16 ++++------------
1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/arch/s390/kernel/unwind_bc.c b/arch/s390/kernel/unwind_bc.c
index 8fc9daae47a2..b407b5531f11 100644
--- a/arch/s390/kernel/unwind_bc.c
+++ b/arch/s390/kernel/unwind_bc.c
@@ -80,12 +80,8 @@ bool unwind_next_frame(struct unwind_state *state)
}
}

-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- /* Decode any ftrace redirection */
- if (ip == (unsigned long) return_to_handler)
- ip = ftrace_graph_ret_addr(state->task, &state->graph_idx,
- ip, (void *) sp);
-#endif
+ ip = ftrace_graph_ret_addr(state->task, &state->graph_idx,
+ ip, (void *) sp);

/* Update unwind state */
state->sp = sp;
@@ -140,12 +136,8 @@ void __unwind_start(struct unwind_state *state, struct task_struct *task,
reliable = false;
}

-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- /* Decode any ftrace redirection */
- if (ip == (unsigned long) return_to_handler)
- ip = ftrace_graph_ret_addr(state->task, &state->graph_idx,
- ip, NULL);
-#endif
+ ip = ftrace_graph_ret_addr(state->task, &state->graph_idx,
+ ip, NULL);

/* Update unwind state */
state->sp = sp;
--
2.23.0