[frederic-dynticks:rcu/dev 2/5] kernel/rcu/tree_nocb.h:1157:7: warning: variable 'need_rcu_nocb_mask' set but not used

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git rcu/dev
head:   be4d4c3ba8c4ceeba9dc9df4de5451c7261161f3
commit: bdfa2dd80919bc4636fcf606cd21b606d361fd16 [2/5] rcu/nocb: Move rcu_nocb_is_setup to rcu_state
config: x86_64-randconfig-a015 (https://download.01.org/0day-ci/archive/20220217/202202170811.xZp85edb-lkp@xxxxxxxxx/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git/commit/?id=bdfa2dd80919bc4636fcf606cd21b606d361fd16
        git remote add frederic-dynticks https://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
        git fetch --no-tags frederic-dynticks rcu/dev
        git checkout bdfa2dd80919bc4636fcf606cd21b606d361fd16
        # save the config file to linux build tree
        mkdir build_dir
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash kernel/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

   In file included from kernel/rcu/tree.c:4858:
   kernel/rcu/tree_nocb.h: In function 'rcu_init_nohz':
>> kernel/rcu/tree_nocb.h:1157:7: warning: variable 'need_rcu_nocb_mask' set but not used [-Wunused-but-set-variable]
    1157 |  bool need_rcu_nocb_mask = false;
         |       ^~~~~~~~~~~~~~~~~~


vim +/need_rcu_nocb_mask +1157 kernel/rcu/tree_nocb.h

dfcb27540213e8 Frederic Weisbecker 2021-05-19  1153  
dfcb27540213e8 Frederic Weisbecker 2021-05-19  1154  void __init rcu_init_nohz(void)
dfcb27540213e8 Frederic Weisbecker 2021-05-19  1155  {
dfcb27540213e8 Frederic Weisbecker 2021-05-19  1156  	int cpu;
dfcb27540213e8 Frederic Weisbecker 2021-05-19 @1157  	bool need_rcu_nocb_mask = false;
dfcb27540213e8 Frederic Weisbecker 2021-05-19  1158  	struct rcu_data *rdp;
dfcb27540213e8 Frederic Weisbecker 2021-05-19  1159  

:::::: The code at line 1157 was first introduced by commit
:::::: dfcb27540213e8061ecffacd4bd8ed54a310a7b0 rcu/nocb: Start moving nocb code to its own plugin file

:::::: TO: Frederic Weisbecker <frederic@xxxxxxxxxx>
:::::: CC: Paul E. McKenney <paulmck@xxxxxxxxxx>

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0-DAY CI Kernel Test Service, Intel Corporation
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