Le Tue, Feb 24, 2026 at 06:04:32PM -0500, Joel Fernandes a écrit : > The rcu_nocb_cpu_offload() and rcu_nocb_cpu_deoffload() functions are > nearly duplicates. > > Therefore, extract the common logic into rcu_nocb_cpu_toggle_offload() > which takes an 'offload' boolean, and make both exported functions > simple wrappers. > > This eliminates a bunch of duplicate code at the call sites, namely > mutex locking, CPU hotplug locking and CPU online checks. > > Signed-off-by: Joel Fernandes <[email protected]> > --- > kernel/rcu/tree_nocb.h | 89 ++++++++++++++++++++++-------------------- > 1 file changed, 46 insertions(+), 43 deletions(-) > > diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h > index b3337c7231cc..5b041134d6bb 100644 > --- a/kernel/rcu/tree_nocb.h > +++ b/kernel/rcu/tree_nocb.h > @@ -1081,30 +1081,6 @@ static int rcu_nocb_rdp_deoffload(struct rcu_data *rdp) > return 0; > } > > -int rcu_nocb_cpu_deoffload(int cpu) > -{ > - struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); > - int ret = 0; > - > - cpus_read_lock(); > - mutex_lock(&rcu_state.nocb_mutex); > - if (rcu_rdp_is_offloaded(rdp)) { > - if (!cpu_online(cpu)) { > - ret = rcu_nocb_rdp_deoffload(rdp); > - if (!ret) > - cpumask_clear_cpu(cpu, rcu_nocb_mask); > - } else { > - pr_info("NOCB: Cannot CB-deoffload online CPU %d\n", > rdp->cpu); > - ret = -EINVAL; > - } > - } > - mutex_unlock(&rcu_state.nocb_mutex); > - cpus_read_unlock(); > - > - return ret; > -} > -EXPORT_SYMBOL_GPL(rcu_nocb_cpu_deoffload); > - > static bool rcu_nocb_rdp_offload_wait_cond(struct rcu_data *rdp) > { > unsigned long flags; > @@ -1149,27 +1125,54 @@ static int rcu_nocb_rdp_offload(struct rcu_data *rdp) > return 0; > } > > +/* Common helper for CPU offload/deoffload operations. */ > +static int rcu_nocb_cpu_toggle_offload(int cpu, bool offload) > +{ > + struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); > + bool currently_offloaded; > + int ret = 0; > + > + cpus_read_lock(); > + mutex_lock(&rcu_state.nocb_mutex); > + > + currently_offloaded = rcu_rdp_is_offloaded(rdp);
Do we really need that extra variable? Reviewed-by: Frederic Weisbecker <[email protected]> -- Frederic Weisbecker SUSE Labs
