[vbabka:slab-remove-slab-v1r0 19/22] mm/memcontrol.c:2888:5: warning: no previous prototype for function 'memcg_alloc_slab_cgroups'

[vbabka:slab-remove-slab-v1r0 19/22] mm/memcontrol.c:2888:5: warning: no previous prototype for function 'memcg_alloc_slab_cgroups'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vbabka/linux.git slab-remove-slab-v1r0
head:   7a5cf1bc55d1877eb85656dd530301fd55599feb
commit: 69d9aaa43fff253c195b3f53537855bcfa14939a [19/22] mm/slab: move memcg related functions from slab.h to slub.c
config: x86_64-rhel-8.3-rust (https://download.01.org/0day-ci/archive/20231004/202310041934.vgOzHUvw-lkp@intel.com/config)
compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231004/202310041934.vgOzHUvw-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202310041934.vgOzHUvw-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> mm/memcontrol.c:2888:5: warning: no previous prototype for function 'memcg_alloc_slab_cgroups' [-Wmissing-prototypes]
   int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s,
       ^
   mm/memcontrol.c:2888:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s,
   ^
   static 
>> mm/memcontrol.c:3163:6: warning: no previous prototype for function 'mod_objcg_state' [-Wmissing-prototypes]
   void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
        ^
   mm/memcontrol.c:3163:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
   ^
   static 
   2 warnings generated.


vim +/memcg_alloc_slab_cgroups +2888 mm/memcontrol.c

a7ebf564de325e Waiman Long     2021-12-10  2887  
4b5f8d9a895ada Vlastimil Babka 2021-11-02 @2888  int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s,
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2889  				 gfp_t gfp, bool new_slab)
10befea91b61c4 Roman Gushchin  2020-08-06  2890  {
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2891  	unsigned int objects = objs_per_slab(s, slab);
2e9bd483159939 Roman Gushchin  2021-02-24  2892  	unsigned long memcg_data;
10befea91b61c4 Roman Gushchin  2020-08-06  2893  	void *vec;
10befea91b61c4 Roman Gushchin  2020-08-06  2894  
41eb5df1cbc9b3 Waiman Long     2021-06-28  2895  	gfp &= ~OBJCGS_CLEAR_MASK;
10befea91b61c4 Roman Gushchin  2020-08-06  2896  	vec = kcalloc_node(objects, sizeof(struct obj_cgroup *), gfp,
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2897  			   slab_nid(slab));
10befea91b61c4 Roman Gushchin  2020-08-06  2898  	if (!vec)
10befea91b61c4 Roman Gushchin  2020-08-06  2899  		return -ENOMEM;
10befea91b61c4 Roman Gushchin  2020-08-06  2900  
2e9bd483159939 Roman Gushchin  2021-02-24  2901  	memcg_data = (unsigned long) vec | MEMCG_DATA_OBJCGS;
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2902  	if (new_slab) {
2e9bd483159939 Roman Gushchin  2021-02-24  2903  		/*
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2904  		 * If the slab is brand new and nobody can yet access its
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2905  		 * memcg_data, no synchronization is required and memcg_data can
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2906  		 * be simply assigned.
2e9bd483159939 Roman Gushchin  2021-02-24  2907  		 */
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2908  		slab->memcg_data = memcg_data;
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2909  	} else if (cmpxchg(&slab->memcg_data, 0, memcg_data)) {
2e9bd483159939 Roman Gushchin  2021-02-24  2910  		/*
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2911  		 * If the slab is already in use, somebody can allocate and
4b5f8d9a895ada Vlastimil Babka 2021-11-02  2912  		 * assign obj_cgroups in parallel. In this case the existing
2e9bd483159939 Roman Gushchin  2021-02-24  2913  		 * objcg vector should be reused.
2e9bd483159939 Roman Gushchin  2021-02-24  2914  		 */
10befea91b61c4 Roman Gushchin  2020-08-06  2915  		kfree(vec);
2e9bd483159939 Roman Gushchin  2021-02-24  2916  		return 0;
2e9bd483159939 Roman Gushchin  2021-02-24  2917  	}
10befea91b61c4 Roman Gushchin  2020-08-06  2918  
2e9bd483159939 Roman Gushchin  2021-02-24  2919  	kmemleak_not_leak(vec);
10befea91b61c4 Roman Gushchin  2020-08-06  2920  	return 0;
10befea91b61c4 Roman Gushchin  2020-08-06  2921  }
10befea91b61c4 Roman Gushchin  2020-08-06  2922  

:::::: The code at line 2888 was first introduced by commit
:::::: 4b5f8d9a895ada8e0abb58ccd35d9fe229e3a595 mm/memcg: Convert slab objcgs from struct page to struct slab

:::::: TO: Vlastimil Babka <vbabka@suse.cz>
:::::: CC: Vlastimil Babka <vbabka@suse.cz>

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