mm/slub: Refactor note_cmpxchg_failure for better readability

Use IS_ENABLED() and standard if-else to make the code clearer.

Signed-off-by: Ye Liu <liuye@kylinos.cn>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Christoph Lameter (Ampere) <cl@gentwo.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

diff --git a/mm/slub.c b/mm/slub.c
index 9074ce914e9e1ceafe733e3ab0bac413993e7b71..3062f56bf49882538ba5af407de9f69c451f2e29 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3069,18 +3069,17 @@ static inline void note_cmpxchg_failure(const char *n,
 
        pr_info("%s %s: cmpxchg redo ", n, s->name);
 
-#ifdef CONFIG_PREEMPTION
-       if (tid_to_cpu(tid) != tid_to_cpu(actual_tid))
+       if (IS_ENABLED(CONFIG_PREEMPTION) &&
+           tid_to_cpu(tid) != tid_to_cpu(actual_tid)) {
                pr_warn("due to cpu change %d -> %d\n",
                        tid_to_cpu(tid), tid_to_cpu(actual_tid));
-       else
-#endif
-       if (tid_to_event(tid) != tid_to_event(actual_tid))
+       } else if (tid_to_event(tid) != tid_to_event(actual_tid)) {
                pr_warn("due to cpu running other code. Event %ld->%ld\n",
                        tid_to_event(tid), tid_to_event(actual_tid));
-       else
+       } else {
                pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n",
                        actual_tid, tid, next_tid(tid));
+       }
 #endif
        stat(s, CMPXCHG_DOUBLE_CPU_FAIL);
 }