[rcu:dev.2020.04.03a 101/101] kernel/rcu/tasks.h:251:9: error: 'struct task_struct' has no member named 'rcu_tasks_idx'

[kbuild test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev.2020.04.03a
head:   8c64539e2d8fbd96ad4bb60a96c5d9c1ef823572
commit: 8c64539e2d8fbd96ad4bb60a96c5d9c1ef823572 [101/101] squash! ftrace: Use synchronize_rcu_tasks_rude() instead of ftrace_sync()
config: powerpc-defconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout 8c64539e2d8fbd96ad4bb60a96c5d9c1ef823572
        # save the attached .config to linux build tree
        GCC_VERSION=9.3.0 make.cross ARCH=powerpc 

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

All errors (new ones prefixed by >>):

   In file included from kernel/rcu/update.c:563:
   kernel/rcu/tasks.h: In function 'exit_tasks_rcu_start':
>> kernel/rcu/tasks.h:251:9: error: 'struct task_struct' has no member named 'rcu_tasks_idx'
     251 |  current->rcu_tasks_idx = __srcu_read_lock(&tasks_rcu_exit_srcu);
         |         ^~
   kernel/rcu/tasks.h: In function 'exit_tasks_rcu_finish':
   kernel/rcu/tasks.h:263:44: error: 'struct task_struct' has no member named 'rcu_tasks_idx'
     263 |  __srcu_read_unlock(&tasks_rcu_exit_srcu, t->rcu_tasks_idx);
         |                                            ^~

vim +251 kernel/rcu/tasks.h

dfdddf06801dcb Paul E. McKenney 2020-03-03  246  
dfdddf06801dcb Paul E. McKenney 2020-03-03  247  /* Do the srcu_read_lock() for the above synchronize_srcu().  */
dfdddf06801dcb Paul E. McKenney 2020-03-03  248  void exit_tasks_rcu_start(void) __acquires(&tasks_rcu_exit_srcu)
dfdddf06801dcb Paul E. McKenney 2020-03-03  249  {
dfdddf06801dcb Paul E. McKenney 2020-03-03  250  	preempt_disable();
dfdddf06801dcb Paul E. McKenney 2020-03-03 @251  	current->rcu_tasks_idx = __srcu_read_lock(&tasks_rcu_exit_srcu);
dfdddf06801dcb Paul E. McKenney 2020-03-03  252  	preempt_enable();
4dbad397293c85 Paul E. McKenney 2020-03-02  253  }
dfdddf06801dcb Paul E. McKenney 2020-03-03  254  

:::::: The code at line 251 was first introduced by commit
:::::: dfdddf06801dcbee9f3ab515aad75421b3e3e75f rcu-tasks: Refactor RCU-tasks to allow variants to be added

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

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip