From: Ye Liu <ye.liu@linux.dev>
To: Andrew Morton <akpm@linux-foundation.org>,
Uladzislau Rezki <urezki@gmail.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Ye Liu <liuye@kylinos.cn>
Subject: [PATCH 2/3] mm/vmalloc: extract vmap_insert_free_area helper
Date: Mon, 14 Sep 2026 11:34:01 +0800 [thread overview]
Message-ID: <20260914-vmalloc_study-v1-2-526f68559706@linux.dev> (raw)
In-Reply-To: <20260914-vmalloc_study-v1-0-526f68559706@linux.dev>
From: Ye Liu <liuye@kylinos.cn>
The allocation and insertion of a free vmap_area is duplicated
between the loop body and the tail of vmap_init_free_space. Factor
it into a small helper so the main function only deals with computing
the free gaps between busy regions.
Signed-off-by: Ye Liu <liuye@kylinos.cn>
---
mm/vmalloc.c | 41 ++++++++++++++++++-----------------------
1 file changed, 18 insertions(+), 23 deletions(-)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 117483dd048c..797933ba9451 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -5433,11 +5433,23 @@ module_init(proc_vmalloc_init);
#endif
+static void __init vmap_insert_free_area(unsigned long start, unsigned long end)
+{
+ struct vmap_area *free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
+
+ if (!WARN_ON_ONCE(!free)) {
+ free->va_start = start;
+ free->va_end = end;
+ insert_vmap_area_augment(free, NULL,
+ &free_vmap_area_root,
+ &free_vmap_area_list);
+ }
+}
+
static void __init vmap_init_free_space(void)
{
unsigned long vmap_start = 1;
const unsigned long vmap_end = ULONG_MAX;
- struct vmap_area *free;
struct vm_struct *busy;
/*
@@ -5447,32 +5459,15 @@ static void __init vmap_init_free_space(void)
* |<--------------------------------->|
*/
for (busy = vmlist; busy; busy = busy->next) {
- if ((unsigned long) busy->addr - vmap_start > 0) {
- free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
- if (!WARN_ON_ONCE(!free)) {
- free->va_start = vmap_start;
- free->va_end = (unsigned long) busy->addr;
-
- insert_vmap_area_augment(free, NULL,
- &free_vmap_area_root,
- &free_vmap_area_list);
- }
- }
+ if ((unsigned long)busy->addr - vmap_start > 0)
+ vmap_insert_free_area(vmap_start,
+ (unsigned long)busy->addr);
vmap_start = (unsigned long) busy->addr + busy->size;
}
- if (vmap_end - vmap_start > 0) {
- free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT);
- if (!WARN_ON_ONCE(!free)) {
- free->va_start = vmap_start;
- free->va_end = vmap_end;
-
- insert_vmap_area_augment(free, NULL,
- &free_vmap_area_root,
- &free_vmap_area_list);
- }
- }
+ if (vmap_end - vmap_start > 0)
+ vmap_insert_free_area(vmap_start, vmap_end);
}
static void vmap_init_nodes(void)
--
2.25.1
next prev parent reply other threads:[~2026-09-14 3:34 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-14 3:33 [PATCH 0/3] mm/vmalloc: minor cleanups Ye Liu
2026-09-14 3:34 ` [PATCH 1/3] mm/vmalloc: group xa_init with vbq field initializations Ye Liu
2026-09-14 16:57 ` Uladzislau Rezki
2026-09-15 3:52 ` Dev Jain
2026-09-14 3:34 ` Ye Liu [this message]
2026-09-14 17:02 ` [PATCH 2/3] mm/vmalloc: extract vmap_insert_free_area helper Uladzislau Rezki
2026-09-15 2:25 ` Ye Liu
2026-09-15 3:48 ` Dev Jain
2026-09-14 3:34 ` [PATCH 3/3] mm/vmalloc: extract show_busy_info from vmalloc_info_show Ye Liu
2026-09-14 17:10 ` Uladzislau Rezki
2026-09-15 2:26 ` Ye Liu
2026-09-15 4:38 ` Andrew Morton
2026-09-15 4:23 ` Dev Jain
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