From: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Subject: 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.
[cuibixuan@xxxxxxxxxx: fix warning when CONFIG_TRACING is not defined]
Link: https://lkml.kernel.org/r/20210531033426.74031-1-cuibixuan@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20210520084809.8576-13-mgorman@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Bixuan Cui <cuibixuan@xxxxxxxxxx>
Reviewed-by: Yang Shi <shy828301@xxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Dan Streetman <ddstreet@xxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mmap_lock.c | 59 +++++++++++++++++++++++++----------------------
1 file changed, 32 insertions(+), 27 deletions(-)
--- a/mm/mmap_lock.c~mm-mmap_lock-remove-dead-code-for-config_tracing-configurations
+++ a/mm/mmap_lock.c
@@ -153,6 +153,37 @@ static inline void put_memcg_path_buf(vo
rcu_read_unlock();
}
+#define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \
+ do { \
+ const char *memcg_path; \
+ preempt_disable(); \
+ memcg_path = get_mm_memcg_path(mm); \
+ trace_mmap_lock_##type(mm, \
+ memcg_path != NULL ? memcg_path : "", \
+ ##__VA_ARGS__); \
+ if (likely(memcg_path != NULL)) \
+ put_memcg_path_buf(); \
+ preempt_enable(); \
+ } while (0)
+
+#else /* !CONFIG_MEMCG */
+
+int trace_mmap_lock_reg(void)
+{
+ return 0;
+}
+
+void trace_mmap_lock_unreg(void)
+{
+}
+
+#define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \
+ trace_mmap_lock_##type(mm, "", ##__VA_ARGS__)
+
+#endif /* CONFIG_MEMCG */
+
+#ifdef CONFIG_TRACING
+#ifdef CONFIG_MEMCG
/*
* Write the given mm_struct's memcg path to a percpu buffer, and return a
* pointer to it. If the path cannot be determined, or no buffer was available
@@ -187,33 +218,6 @@ out:
return buf;
}
-#define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \
- do { \
- const char *memcg_path; \
- local_lock(&memcg_paths.lock); \
- memcg_path = get_mm_memcg_path(mm); \
- trace_mmap_lock_##type(mm, \
- memcg_path != NULL ? memcg_path : "", \
- ##__VA_ARGS__); \
- if (likely(memcg_path != NULL)) \
- put_memcg_path_buf(); \
- local_unlock(&memcg_paths.lock); \
- } while (0)
-
-#else /* !CONFIG_MEMCG */
-
-int trace_mmap_lock_reg(void)
-{
- return 0;
-}
-
-void trace_mmap_lock_unreg(void)
-{
-}
-
-#define TRACE_MMAP_LOCK_EVENT(type, mm, ...) \
- trace_mmap_lock_##type(mm, "", ##__VA_ARGS__)
-
#endif /* CONFIG_MEMCG */
/*
@@ -239,3 +243,4 @@ void __mmap_lock_do_trace_released(struc
TRACE_MMAP_LOCK_EVENT(released, mm, write);
}
EXPORT_SYMBOL(__mmap_lock_do_trace_released);
+#endif /* CONFIG_TRACING */
_
