[PATCH v2] stacktrace: cleanup inconsistent variable type

[Walter Wu]

Modify the variable type of 'skip' member of struct stack_trace.
In theory, the 'skip' variable type should be unsigned int.
There are two reasons:
- The 'skip' only has two situation, 1)Positive value, 2)Zero
- The 'skip' of struct stack_trace has inconsistent type with struct
  stack_trace_data, it makes a bit confusion in the relationship between
  struct stack_trace and stack_trace_data.

Signed-off-by: Walter Wu <walter-zh.wu@xxxxxxxxxxxx>
Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Bart Van Assche <bvanassche@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
changes in v2:
modify the commit log to describe the matter more clearly.

---
 include/linux/stacktrace.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/stacktrace.h b/include/linux/stacktrace.h
index 83bd8cb475d7..b7af8cc13eda 100644
--- a/include/linux/stacktrace.h
+++ b/include/linux/stacktrace.h
@@ -64,7 +64,7 @@ void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
 struct stack_trace {
 	unsigned int nr_entries, max_entries;
 	unsigned long *entries;
-	int skip;	/* input argument: How many entries to skip */
+	unsigned int skip;	/* input argument: How many entries to skip */
 };
 
 extern void save_stack_trace(struct stack_trace *trace);
-- 
2.18.0