From: Tatsuya S <[email protected]>
On setting set_ftrace_pid, a extra entry generated by ftrace_pid_func()
is shown on stack trace(CONFIG_UNWINDER_FRAME_POINTER=y).
[004] ..... 68.459382: <stack trace>
=> 0xffffffffa00090af
=> ksys_read
=> __x64_sys_read
=> x64_sys_call
=> do_syscall_64
=> entry_SYSCALL_64_after_hwframe
To resolve this issue, increment skip count
in function_stack_trace_call() if pids are set.
Link: https://lore.kernel.org/linux-trace-kernel/[email protected]
Signed-off-by: Tatsuya S <[email protected]>
[ Rebased to current tree ]
Signed-off-by: Steven Rostedt (Google) <[email protected]>
---
kernel/trace/trace_functions.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 13bf2415245d..3b0cea37e029 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -231,6 +231,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
long disabled;
int cpu;
unsigned int trace_ctx;
+ int skip = STACK_SKIP;
if (unlikely(!tr->function_enabled))
return;
@@ -247,7 +248,11 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
if (likely(disabled == 1)) {
trace_ctx = tracing_gen_ctx_flags(flags);
trace_function(tr, ip, parent_ip, trace_ctx);
- __trace_stack(tr, trace_ctx, STACK_SKIP);
+#ifdef CONFIG_UNWINDER_FRAME_POINTER
+ if (ftrace_pids_enabled(op))
+ skip++;
+#endif
+ __trace_stack(tr, trace_ctx, skip);
}
atomic_dec(&data->disabled);
--
2.43.0