task_stack: uninline stack_not_used

Given that stack_not_used() is not performance critical function
uninline it.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Pasha Tatashin <[email protected]>
Acked-by: Shakeel Butt <[email protected]>
Cc: Domenico Cerasuolo <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Li Zhijian <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Nhat Pham <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

1 files changed, 3 insertions, 15 deletions

diff --git a/include/linux/sched/task_stack.h b/include/linux/sched/task_stack.h
index ccd72b978e1f..bf10bdb487dd 100644
--- a/include/linux/sched/task_stack.h
+++ b/include/linux/sched/task_stack.h
@@ -95,23 +95,11 @@ static inline int object_is_on_stack(const void *obj)
 extern void thread_stack_cache_init(void);
 
 #ifdef CONFIG_DEBUG_STACK_USAGE
+unsigned long stack_not_used(struct task_struct *p);
+#else
 static inline unsigned long stack_not_used(struct task_struct *p)
 {
-	unsigned long *n = end_of_stack(p);
-
-	do { 	/* Skip over canary */
-# ifdef CONFIG_STACK_GROWSUP
-		n--;
-# else
-		n++;
-# endif
-	} while (!*n);
-
-# ifdef CONFIG_STACK_GROWSUP
-	return (unsigned long)end_of_stack(p) - (unsigned long)n;
-# else
-	return (unsigned long)n - (unsigned long)end_of_stack(p);
-# endif
+	return 0;
 }
 #endif
 extern void set_task_stack_end_magic(struct task_struct *tsk);