diff mbox series

[v3,1/2] mm/slub: limit number of node partial slabs only in cache creation

Message ID 20220307074057.902222-2-42.hyeyoo@gmail.com (mailing list archive)
State New
Headers show
Series slab cleanups | expand

Commit Message

Hyeonggon Yoo March 7, 2022, 7:40 a.m. UTC 
SLUB sets number of minimum partial slabs for node (min_partial)
using set_min_partial(). SLUB holds at least min_partial slabs even if
they're empty to avoid excessive use of page allocator.

set_min_partial() limits value of min_partial limits value of
min_partial MIN_PARTIAL and MAX_PARTIAL. As set_min_partial() can be
called by min_partial_store() too, Only limit value of min_partial
in kmem_cache_open() so that it can be changed to value that a user wants.

[ rientjes@google.com: Fold set_min_partial() into its callers ]

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
---
 mm/slub.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

Comments

Roman Gushchin March 8, 2022, 4:48 a.m. UTC | #1 
On Mon, Mar 07, 2022 at 07:40:55AM +0000, Hyeonggon Yoo wrote:
> SLUB sets number of minimum partial slabs for node (min_partial)
> using set_min_partial(). SLUB holds at least min_partial slabs even if
> they're empty to avoid excessive use of page allocator.
> 
> set_min_partial() limits value of min_partial limits value of
> min_partial MIN_PARTIAL and MAX_PARTIAL. As set_min_partial() can be
> called by min_partial_store() too, Only limit value of min_partial
> in kmem_cache_open() so that it can be changed to value that a user wants.
> 
> [ rientjes@google.com: Fold set_min_partial() into its callers ]
> 
> Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
> Reviewed-by: Vlastimil Babka <vbabka@suse.cz>

LGTM!

Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
diff mbox series

Patch

diff --git a/mm/slub.c b/mm/slub.c
index 261474092e43..1ce09b0347ad 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4000,15 +4000,6 @@  static int init_kmem_cache_nodes(struct kmem_cache *s)
 	return 1;
 }
 
-static void set_min_partial(struct kmem_cache *s, unsigned long min)
-{
-	if (min < MIN_PARTIAL)
-		min = MIN_PARTIAL;
-	else if (min > MAX_PARTIAL)
-		min = MAX_PARTIAL;
-	s->min_partial = min;
-}
-
 static void set_cpu_partial(struct kmem_cache *s)
 {
 #ifdef CONFIG_SLUB_CPU_PARTIAL
@@ -4215,7 +4206,8 @@  static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags)
 	 * The larger the object size is, the more slabs we want on the partial
 	 * list to avoid pounding the page allocator excessively.
 	 */
-	set_min_partial(s, ilog2(s->size) / 2);
+	s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2);
+	s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial);
 
 	set_cpu_partial(s);
 
@@ -5396,7 +5388,7 @@  static ssize_t min_partial_store(struct kmem_cache *s, const char *buf,
 	if (err)
 		return err;
 
-	set_min_partial(s, min);
+	s->min_partial = min;
 	return length;
 }
 SLAB_ATTR(min_partial);