Subject: linux-next: build failure after merge of the rcu tree

From: Stephen Rothwell <[email-masked]>
Date: Thu, 25 Jun 2020 12:57:53 +1000

Hi all,

After merging the rcu tree, today's linux-next build (powerpc
ppc64_defconfig) failed like this:

kernel/rcu/tree.c: In function 'rcu_dynticks_eqs_enter':
kernel/rcu/tree.c:251:8: error: implicit declaration of function 'arch_atomic_add_return'; did you mean 'atomic_add_return'? [-Werror=implicit-function-declaration]
  251 |  seq = arch_atomic_add_return(RCU_DYNTICK_CTRL_CTR, &rdp->dynticks);
      |        ^~~~~~~~~~~~~~~~~~~~~~
      |        atomic_add_return
kernel/rcu/tree.c: In function 'rcu_dynticks_eqs_exit':
kernel/rcu/tree.c:281:3: error: implicit declaration of function 'arch_atomic_andnot'; did you mean 'atomic_andnot'? [-Werror=implicit-function-declaration]
  281 |   arch_atomic_andnot(RCU_DYNTICK_CTRL_MASK, &rdp->dynticks);
      |   ^~~~~~~~~~~~~~~~~~
      |   atomic_andnot
kernel/rcu/tree.c: In function 'rcu_dynticks_curr_cpu_in_eqs':
kernel/rcu/tree.c:314:11: error: implicit declaration of function 'arch_atomic_read'; did you mean 'atomic_read'? [-Werror=implicit-function-declaration]
  314 |  return !(arch_atomic_read(&rdp->dynticks) & RCU_DYNTICK_CTRL_CTR);
      |           ^~~~~~~~~~~~~~~~
      |           atomic_read

Caused by commit

  d2f8491368e5 ("rcu: Fixup noinstr warnings")

I reverted that commit for today.

-- 
Cheers,
Stephen Rothwell