[GIT PULL] x86/debug change for v4.15

[GIT PULL] x86/debug change for v4.15

[Ingo Molnar]

Linus,

Please pull the latest x86-debug-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-debug-for-linus

   # HEAD: 77072f09eab19326dd2424c8dad0a443341a228f x86/stacktrace: Avoid recording save_stack_trace() wrappers

A single change enhancing stack traces by hiding wrapper function entries.

 Thanks,

	Ingo

------------------>
Vlastimil Babka (1):
      x86/stacktrace: Avoid recording save_stack_trace() wrappers


 arch/x86/kernel/stacktrace.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
index 8dabd7bf1673..77835bc021c7 100644
--- a/arch/x86/kernel/stacktrace.c
+++ b/arch/x86/kernel/stacktrace.c
@@ -30,7 +30,7 @@ static int save_stack_address(struct stack_trace *trace, unsigned long addr,
 	return 0;
 }
 
-static void __save_stack_trace(struct stack_trace *trace,
+static void noinline __save_stack_trace(struct stack_trace *trace,
 			       struct task_struct *task, struct pt_regs *regs,
 			       bool nosched)
 {
@@ -56,6 +56,7 @@ static void __save_stack_trace(struct stack_trace *trace,
  */
 void save_stack_trace(struct stack_trace *trace)
 {
+	trace->skip++;
 	__save_stack_trace(trace, current, NULL, false);
 }
 EXPORT_SYMBOL_GPL(save_stack_trace);
@@ -70,6 +71,8 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
 	if (!try_get_task_stack(tsk))
 		return;
 
+	if (tsk == current)
+		trace->skip++;
 	__save_stack_trace(trace, tsk, NULL, true);
 
 	put_task_stack(tsk);
@@ -88,8 +91,9 @@ EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
 	}							\
 })
 
-static int __save_stack_trace_reliable(struct stack_trace *trace,
-				       struct task_struct *task)
+static int __always_inline
+__save_stack_trace_reliable(struct stack_trace *trace,
+			    struct task_struct *task)
 {
 	struct unwind_state state;
 	struct pt_regs *regs;