[PATCH v3 2/2] mm/alloc_tag: add the CONFIG_ARCH_NEEDS_WEAK_PER_CPU macro when statically defining the percpu variable _shared_alloc_tag

[Hao Ge <hao.ge@linux.dev>]

From: Hao Ge <gehao@kylinos.cn>

Given the introduction of the CONFIG_ARCH_NEEDS_WEAK_PER_CPU macro,
we can now conditionally define the perpcu variable _shared_alloc_tag
based on its value. This allows architectures(such as s390/alpha) that
require weak definitions for percpu variables in modules to include
the definition,while others can omit it via compile-time exclusion.

Suggested-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Hao Ge <gehao@kylinos.cn>
---
 lib/alloc_tag.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index c7f602fa7b23..14fd66f26e42 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -24,8 +24,10 @@ static bool mem_profiling_support;
 
 static struct codetag_type *alloc_tag_cttype;
 
+#ifdef CONFIG_ARCH_NEEDS_WEAK_PER_CPU
 DEFINE_PER_CPU(struct alloc_tag_counters, _shared_alloc_tag);
 EXPORT_SYMBOL(_shared_alloc_tag);
+#endif
 
 DEFINE_STATIC_KEY_MAYBE(CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT,
 			mem_alloc_profiling_key);
-- 
2.25.1