Re: [PATCH] mm/slab: stop exporting kvfree_rcu_barrier[_on_cache]()

["Vlastimil Babka (SUSE)" <vbabka@kernel.org>]

On 7/30/26 22:59, Paul E. McKenney wrote:
> On Thu, Jul 30, 2026 at 04:32:46PM +0200, Vlastimil Babka (SUSE) wrote:
>> No module code calls these functions directly. Seems it was always the
>> case. Remove the exports.
>> 
>> Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
> 
> Acked-by: Paul E. McKenney <paulmck@kernel.org>

Thanks!

> Which reminds me...  Are you guys interested in taking the kfree_rcu()
> test code from kernel/rcu/rcuscale.c?  See for example the kfree_rcu_test
> module parameter.

Hmm, we have a slub kunit test, but I think no such torture/scaling test
infra. Maybe once we have that? What do you think, Harry?



> 							Thanx, Paul
> 
>> ---
>> Based on slab/for-7.3/kfree_rcu_nolock
>> ---
>>  mm/slab_common.c | 4 ----
>>  1 file changed, 4 deletions(-)
>> 
>> diff --git a/mm/slab_common.c b/mm/slab_common.c
>> index 6750dfa27367..cd155ffc2762 100644
>> --- a/mm/slab_common.c
>> +++ b/mm/slab_common.c
>> @@ -1329,14 +1329,12 @@ void kvfree_rcu_barrier(void)
>>  	deferred_work_barrier();
>>  	rcu_barrier();
>>  }
>> -EXPORT_SYMBOL_GPL(kvfree_rcu_barrier);
>>  
>>  void kvfree_rcu_barrier_on_cache(struct kmem_cache *s)
>>  {
>>  	deferred_work_barrier();
>>  	rcu_barrier();
>>  }
>> -EXPORT_SYMBOL_GPL(kvfree_rcu_barrier_on_cache);
>>  
>>  void __init kvfree_rcu_init(void)
>>  {
>> @@ -2163,7 +2161,6 @@ void kvfree_rcu_barrier(void)
>>  	flush_all_rcu_sheaves();
>>  	__kvfree_rcu_barrier();
>>  }
>> -EXPORT_SYMBOL_GPL(kvfree_rcu_barrier);
>>  
>>  /**
>>   * kvfree_rcu_barrier_on_cache - Wait for in-flight kvfree_rcu() calls on a
>> @@ -2186,7 +2183,6 @@ void kvfree_rcu_barrier_on_cache(struct kmem_cache *s)
>>  	rcu_barrier();
>>  	__kvfree_rcu_barrier();
>>  }
>> -EXPORT_SYMBOL_GPL(kvfree_rcu_barrier_on_cache);
>>  
>>  static unsigned long
>>  kfree_rcu_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
>> 
>> ---
>> base-commit: b01f6ed9ff0c4581fc669044fa5b82a93b4ef144
>> change-id: 20260730-unexport-barriers-439b3f69f791
>> 
>>