Hi Hongchen, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on tj-cgroup/for-next] [also build test WARNING on v5.18 next-20220527] [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/intel-lab-lkp/linux/commits/Hongchen-Zhang/cgroup-wait-for-css-offline-when-rmdir/20220527-104105 base: https://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git for-next config: um-i386_defconfig (https://download.01.org/0day-ci/archive/20220527/202205271657.MRX54zi5-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-1) 11.3.0 reproduce (this is a W=1 build): # https://github.com/intel-lab-lkp/linux/commit/9cd51af8f62de826ed76ffb6a63dce3d14926a03 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Hongchen-Zhang/cgroup-wait-for-css-offline-when-rmdir/20220527-104105 git checkout 9cd51af8f62de826ed76ffb6a63dce3d14926a03 # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=um SUBARCH=i386 SHELL=/bin/bash kernel/cgroup/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> kernel/cgroup/cgroup.c:3024:6: warning: no previous prototype for 'cgroup_wait_css_offline' [-Wmissing-prototypes] 3024 | void cgroup_wait_css_offline(struct cgroup *cgrp) | ^~~~~~~~~~~~~~~~~~~~~~~ vim +/cgroup_wait_css_offline +3024 kernel/cgroup/cgroup.c 3022 3023 /* wait all cgrp's csses become offlined */ > 3024 void cgroup_wait_css_offline(struct cgroup *cgrp) 3025 { 3026 struct cgroup_subsys *ss; 3027 int ssid; 3028 3029 lockdep_assert_held(&cgroup_mutex); 3030 for_each_subsys(ss, ssid) { 3031 struct cgroup_subsys_state *css = cgroup_css(cgrp, ss); 3032 DEFINE_WAIT(wait); 3033 3034 if (!css || !percpu_ref_is_dying(&css->refcnt)) 3035 continue; 3036 3037 prepare_to_wait(&cgrp->offline_waitq, &wait, 3038 TASK_UNINTERRUPTIBLE); 3039 3040 mutex_unlock(&cgroup_mutex); 3041 schedule(); 3042 finish_wait(&cgrp->offline_waitq, &wait); 3043 3044 mutex_lock(&cgroup_mutex); 3045 } 3046 } 3047 -- 0-DAY CI Kernel Test Service https://01.org/lkp
