diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 6c6569e0586c..bef1dc91bfbe 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3842,10 +3842,9 @@ void rcu_cpu_starting(unsigned int cpu) { unsigned long flags; unsigned long mask; - int nbits; - unsigned long oldmask; struct rcu_data *rdp; struct rcu_node *rnp; + bool newcpu; if (per_cpu(rcu_cpu_started, cpu)) return; @@ -3857,12 +3856,10 @@ void rcu_cpu_starting(unsigned int cpu) mask = rdp->grpmask; raw_spin_lock_irqsave_rcu_node(rnp, flags); WRITE_ONCE(rnp->qsmaskinitnext, rnp->qsmaskinitnext | mask); - oldmask = rnp->expmaskinitnext; + newcpu = !(rnp->expmaskinitnext & mask); rnp->expmaskinitnext |= mask; - oldmask ^= rnp->expmaskinitnext; - nbits = bitmap_weight(&oldmask, BITS_PER_LONG); /* Allow lockless access for expedited grace periods. */ - smp_store_release(&rcu_state.ncpus, rcu_state.ncpus + nbits); /* ^^^ */ + smp_store_release(&rcu_state.ncpus, rcu_state.ncpus + newcpu); /* ^^^ */ ASSERT_EXCLUSIVE_WRITER(rcu_state.ncpus); rcu_gpnum_ovf(rnp, rdp); /* Offline-induced counter wrap? */ rdp->rcu_onl_gp_seq = READ_ONCE(rcu_state.gp_seq);