Hi Yu, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on tip/x86/core] [also build test WARNING on tip/x86/mm tip/sched/core linus/master v5.12-rc2] [cannot apply to cgroup/for-next tip/perf/core hnaz-linux-mm/master next-20210312] [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] url: https://github.com/0day-ci/linux/commits/Yu-Zhao/Multigenerational-LRU/20... base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git d0962f2b24c99889a386f0658c71535f56358f77 compiler: s390-linux-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; cppcheck possible warnings: (new ones prefixed by >>, may not real problems) mm/vmscan.c:4107:22: warning: Local variable kswapd shadows outer function [shadowFunction] struct task_struct *kswapd = NODE_DATA(nid)->kswapd; ^ mm/vmscan.c:3909:12: note: Shadowed declaration static int kswapd(void *p) ^ mm/vmscan.c:4107:22: note: Shadow variable struct task_struct *kswapd = NODE_DATA(nid)->kswapd; ^ vim +6140 mm/vmscan.c 6106 6107 static ssize_t lru_gen_debugfs_write(struct file *file, const char __user *src, 6108 size_t len, loff_t *pos) 6109 { 6110 void *buf; 6111 char *cur, *next; 6112 int err = 0; 6113 6114 buf = kvmalloc(len + 1, GFP_USER); 6115 if (!buf) 6116 return -ENOMEM; 6117 6118 if (copy_from_user(buf, src, len)) { 6119 kvfree(buf); 6120 return -EFAULT; 6121 } 6122 6123 next = buf; 6124 next[len] = '\0'; 6125 6126 while ((cur = strsep(&next, ",;\n"))) { 6127 int n; 6128 int end; 6129 char cmd; 6130 int memcg_id; 6131 int nid; 6132 unsigned long seq; 6133 int swappiness = -1; 6134 unsigned long nr_to_reclaim = -1; 6135 6136 cur = skip_spaces(cur); 6137 if (!*cur) 6138 continue; 6139 6141 &seq, &end, &swappiness, &end, &nr_to_reclaim, &end); 6142 if (n < 4 || cur[end]) { 6143 err = -EINVAL; 6144 break; 6145 } 6146 6147 err = advance_seq(cmd, memcg_id, nid, seq, swappiness, nr_to_reclaim); 6148 if (err) 6149 break; 6150 } 6151 6152 kvfree(buf); 6153 6154 return err ? : len; 6155 } 6156 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org