Re: mm/slub.c:2077:1: error: unused function 'prepare_slab_obj_exts_hook'

[Suren Baghdasaryan]

On Thu, Jul 4, 2024 at 5:35 PM kernel test robot <lkp@xxxxxxxxx> wrote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head:   661e504db04c6b7278737ee3a9116738536b4ed4
> commit: b4601d096aac8ed26afa88ef8b249975b0530ca1 mm/slab: fix 'variable obj_exts set but not used' warning
> date:   10 days ago
> config: x86_64-sof-customedconfig-amd-defconfig (https://download.01.org/0day-ci/archive/20240705/202407050845.zNONqauD-lkp@xxxxxxxxx/config)
> compiler: clang version 18.1.5 (https://github.com/llvm/llvm-project 617a15a9eac96088ae5e9134248d8236e34b91b1)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240705/202407050845.zNONqauD-lkp@xxxxxxxxx/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@xxxxxxxxx>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202407050845.zNONqauD-lkp@xxxxxxxxx/

Fix is posted at
https://lore.kernel.org/all/20240711170216.1149695-1-surenb@xxxxxxxxxx/
over slab/for-next baseline because that branch contains another code
refactoring [1] which would cause merge conflicts.

[1] https://lore.kernel.org/all/20240704135941.1145038-1-surenb@xxxxxxxxxx/

>
> All errors (new ones prefixed by >>):
>
> >> mm/slub.c:2077:1: error: unused function 'prepare_slab_obj_exts_hook' [-Werror,-Wunused-function]
>     2077 | prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
>          | ^~~~~~~~~~~~~~~~~~~~~~~~~~
>    1 error generated.
>
>
> vim +/prepare_slab_obj_exts_hook +2077 mm/slub.c
>
> 0bedcc66d2a43a Vlastimil Babka    2023-10-03  2075
> 4b8736964640fe Suren Baghdasaryan 2024-03-21  2076  static inline struct slabobj_ext *
> 4b8736964640fe Suren Baghdasaryan 2024-03-21 @2077  prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
> 3450a0e5a6fc4c Vlastimil Babka    2023-11-13  2078  {
> 4b8736964640fe Suren Baghdasaryan 2024-03-21  2079      return NULL;
> 4b8736964640fe Suren Baghdasaryan 2024-03-21  2080  }
> 3450a0e5a6fc4c Vlastimil Babka    2023-11-13  2081
>
> :::::: The code at line 2077 was first introduced by commit
> :::::: 4b8736964640fe160724e7135dc62883bddcdace mm/slab: add allocation accounting into slab allocation and free paths
>
> :::::: TO: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> :::::: CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
>
> --
> 0-DAY CI Kernel Test Service
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