Re: [PATCH v3 4/4] mm: memcg: use non-unified stats flushing for userspace reads

From: kernel test robot
Date: Wed Aug 30 2023 - 23:08:57 EST


Hi Yosry,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on linus/master next-20230830]
[cannot apply to v6.5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Yosry-Ahmed/mm-memcg-properly-name-and-document-unified-stats-flushing/20230831-015518
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/20230830175335.1536008-5-yosryahmed%40google.com
patch subject: [PATCH v3 4/4] mm: memcg: use non-unified stats flushing for userspace reads
config: i386-randconfig-r013-20230831 (https://download.01.org/0day-ci/archive/20230831/202308311025.538QuXBV-lkp@xxxxxxxxx/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/20230831/202308311025.538QuXBV-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/202308311025.538QuXBV-lkp@xxxxxxxxx/

All warnings (new ones prefixed by >>):

>> mm/memcontrol.c:667:6: warning: no previous prototype for function 'mem_cgroup_user_flush_stats' [-Wmissing-prototypes]
void mem_cgroup_user_flush_stats(struct mem_cgroup *memcg)
^
mm/memcontrol.c:667:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
void mem_cgroup_user_flush_stats(struct mem_cgroup *memcg)
^
static
1 warning generated.


vim +/mem_cgroup_user_flush_stats +667 mm/memcontrol.c

658
659 /*
660 * mem_cgroup_user_flush_stats - do a stats flush for a user read
661 * @memcg: memory cgroup to flush
662 *
663 * Flush the subtree of @memcg. A mutex is used for userspace readers to gate
664 * the global rstat spinlock. This protects in-kernel flushers from userspace
665 * readers hogging the lock.
666 */
> 667 void mem_cgroup_user_flush_stats(struct mem_cgroup *memcg)
668 {
669 mutex_lock(&stats_user_flush_mutex);
670 do_stats_flush(memcg);
671 mutex_unlock(&stats_user_flush_mutex);
672 }
673

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki