mm/mmap_lock: remove dead code for !CONFIG_TRACING configurations

make W=1 generates the following warning in mmap_lock.c for allnoconfig

  mm/mmap_lock.c:213:6: warning: no previous prototype for `__mmap_lock_do_trace_start_locking' [-Wmissing-prototypes]
   void __mmap_lock_do_trace_start_locking(struct mm_struct *mm, bool write)
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  mm/mmap_lock.c:219:6: warning: no previous prototype for `__mmap_lock_do_trace_acquire_returned' [-Wmissing-prototypes]
   void __mmap_lock_do_trace_acquire_returned(struct mm_struct *mm, bool write,
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  mm/mmap_lock.c:226:6: warning: no previous prototype for `__mmap_lock_do_trace_released' [-Wmissing-prototypes]
   void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write)

On !CONFIG_TRACING configurations, the code is dead so put it behind an
#ifdef.

Link: https://lkml.kernel.org/r/20210520084809.8576-13-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

diff --git a/mm/mmap_lock.c b/mm/mmap_lock.c
index dcdde4f722a408ff05fa0d5e86ba1465a60ce0ea..03ee85c696ef03b78cdd84f6b7246db4f4028bea 100644 (file)
--- a/mm/mmap_lock.c
+++ b/mm/mmap_lock.c
@@ -205,6 +205,7 @@ void trace_mmap_lock_unreg(void)
 
 #endif /* CONFIG_MEMCG */
 
+#ifdef CONFIG_TRACING
 /*
  * Trace calls must be in a separate file, as otherwise there's a circular
  * dependency between linux/mmap_lock.h and trace/events/mmap_lock.h.
@@ -228,3 +229,4 @@ void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write)
        TRACE_MMAP_LOCK_EVENT(released, mm, write);
 }
 EXPORT_SYMBOL(__mmap_lock_do_trace_released);
+#endif /* CONFIG_TRACING */