mm, x86, ptrace, bts: defer branch trace stopping, remove dead code

Remove the unused free_locked_buffer() API.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

include/linux/mm.h

@@ -1320,7 +1320,6 @@ int vmemmap_populate(struct page *start_page, unsigned long pages, int node);
 void vmemmap_populate_print_last(void);
 
 extern void *alloc_locked_buffer(size_t size);
-extern void free_locked_buffer(void *buffer, size_t size);
 extern void refund_locked_buffer_memory(struct mm_struct *mm, size_t size);
 #endif /* __KERNEL__ */
 #endif /* _LINUX_MM_H */

mm/mlock.c

@@ -671,9 +671,3 @@ void refund_locked_buffer_memory(struct mm_struct *mm, size_t size)
 
 	up_write(&mm->mmap_sem);
 }
-
-void free_locked_buffer(void *buffer, size_t size)
-{
-	refund_locked_buffer_memory(current->mm, size);
-	kfree(buffer);
-}