From 112677d683d31ebd6a8e8b02e0620ae512354b2d Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Tue, 17 Nov 2015 09:43:24 +0900 Subject: [PATCH] x86/ftrace: Add comment on static function tracing There was a confusion between update_ftrace_function() and static function tracing trampoline regarding 3rd parameter (ftrace_ops). Add a comment for clarification. Suggested-by: Steven Rostedt Signed-off-by: Namhyung Kim Cc: H. Peter Anvin Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1447721004-2551-1-git-send-email-namhyung@kernel.org Signed-off-by: Thomas Gleixner --- arch/x86/kernel/mcount_64.S | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S index 94ea120fa21f..87e1762e2bca 100644 --- a/arch/x86/kernel/mcount_64.S +++ b/arch/x86/kernel/mcount_64.S @@ -278,6 +278,12 @@ trace: /* save_mcount_regs fills in first two parameters */ save_mcount_regs + /* + * When DYNAMIC_FTRACE is not defined, ARCH_SUPPORTS_FTRACE_OPS is not + * set (see include/asm/ftrace.h and include/linux/ftrace.h). Only the + * ip and parent ip are used and the list function is called when + * function tracing is enabled. + */ call *ftrace_trace_function restore_mcount_regs