In SLAB, OFF_SLAB caches allocate management structures (currently just the
freelist) from kmalloc caches when placement in a slab page together with
objects would lead to suboptimal memory usage. For SLAB_RECLAIM_ACCOUNT caches,
we can allocate the freelists from the newly introduced reclaimable kmalloc
caches, because shrinking the OFF_SLAB cache will in general result to freeing
of the freelists as well. This should improve accounting and anti-fragmentation
a bit.

Signed-off-by: Vlastimil Babka <vba...@suse.cz>
---
 mm/slab.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/mm/slab.c b/mm/slab.c
index 9515798f37b2..99d779ba2b92 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2140,8 +2140,13 @@ int __kmem_cache_create(struct kmem_cache *cachep, 
slab_flags_t flags)
 #endif
 
        if (OFF_SLAB(cachep)) {
+               /*
+                * If this cache is reclaimable, allocate also freelists from
+                * a reclaimable kmalloc cache.
+                */
                cachep->freelist_cache =
-                       kmalloc_slab(cachep->freelist_size, 0u);
+                       kmalloc_slab(cachep->freelist_size,
+                                    cachep->allocflags & __GFP_RECLAIMABLE);
        }
 
        err = setup_cpu_cache(cachep, gfp);
-- 
2.18.0

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