[PATCH 1/5] mm/vmalloc.c: change purge_ndoes as local static variable

Baoquan He
2025-04-15T02:40:09Z

Static variable 'purge_ndoes' is defined in global scope, while it's
only used in function __purge_vmap_area_lazy(). It mainly serves to
avoid memory allocation repeatedly, especially when NR_CPUS is big.

While a local static variable can also satisfy the demand, and can
improve code readibility. Hence move its definition into
__purge_vmap_area_lazy().

Signed-off-by: Baoquan He <bhe@redhat.com>
---
mm/vmalloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 6ee7fc2ec986..aca1905d3397 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2128,7 +2128,6 @@ static DEFINE_MUTEX(vmap_purge_lock);

/* for per-CPU blocks */
static void purge_fragmented_blocks_allcpus(void);
-static cpumask_t purge_nodes;

static void
reclaim_list_global(struct list_head *head)
@@ -2261,6 +2260,7 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end,
{
unsigned long nr_purged_areas = 0;
unsigned int nr_purge_helpers;
+ static cpumask_t purge_nodes;
unsigned int nr_purge_nodes;
struct vmap_node *vn;
int i;
--
2.41.0