Hi Muchun, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on tj-cgroup/for-next] [also build test WARNING on linus/master v5.15-rc1] [cannot apply to hnaz-mm/master next-20210916] [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/Muchun-Song/Use-obj_cgroup-APIs-... base: https://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git for-next config: x86_64-randconfig-m001-20210916 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/0day-ci/linux/commit/938e77565fc42d6c0d53b0470d75b4055... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Muchun-Song/Use-obj_cgroup-APIs-to-charge-the-LRU-pages/20210916-215452 git checkout 938e77565fc42d6c0d53b0470d75b4055200afe1 # save the attached .config to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): mm/huge_memory.c:516:1: error: expected identifier or '(' before '+' token 516 | +static inline struct mem_cgroup *split_queue_memcg(struct deferred_split *queue) | ^ In file included from include/asm-generic/bug.h:5, from arch/x86/include/asm/bug.h:84, from include/linux/bug.h:5, from include/linux/mmdebug.h:5, from include/linux/mm.h:9, from mm/huge_memory.c:8: mm/huge_memory.c: In function 'split_queue_lock': mm/huge_memory.c:543:15: error: implicit declaration of function 'split_queue_memcg'; did you mean 'split_queue_lock'? [-Werror=implicit-function-declaration] 543 | if (unlikely(split_queue_memcg(queue) != page_memcg(head))) { | ^~~~~~~~~~~~~~~~~ include/linux/compiler.h:78:42: note: in definition of macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ 543 | if (unlikely(split_queue_memcg(queue) != page_memcg(head))) { | ^~ include/linux/compiler.h:78:42: note: in definition of macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ mm/huge_memory.c: In function 'split_queue_lock_irqsave': mm/huge_memory.c:567:40: warning: comparison between pointer and integer 567 | if (unlikely(split_queue_memcg(queue) != page_memcg(head))) { | ^~ include/linux/compiler.h:78:42: note: in definition of macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ mm/huge_memory.c: In function 'deferred_split_huge_page': mm/huge_memory.c:2839:8: warning: assignment to 'struct mem_cgroup *' from 'int' makes pointer from integer without a cast [-Wint-conversion] 2839 | memcg = split_queue_memcg(ds_queue); | ^ cc1: some warnings being treated as errors vim +543 mm/huge_memory.c 533 534 static struct deferred_split *split_queue_lock(struct page *head) 535 { 536 struct deferred_split *queue; 537 538 rcu_read_lock(); 539 retry: 540 queue = page_split_queue(head); 541 spin_lock(&queue->split_queue_lock); 542 544 spin_unlock(&queue->split_queue_lock); 545 goto retry; 546 } 547 548 /* 549 * Preemption is disabled in the internal of spin_lock, which can serve 550 * as RCU read-side critical sections. 551 */ 552 rcu_read_unlock(); 553 554 return queue; 555 } 556 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org