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| author | Paul E. McKenney <paulmck@kernel.org> | 2021-12-10 16:25:20 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-02-08 10:12:28 -0800 |
| commit | 0cabb47af3cfaeb6007ba3868379bbd4daee64cc (patch) | |
| tree | dac582dd53d5dc618eb2d00d742c4c0222a7f05a /kernel/rcu/tree.c | |
| parent | 82980b1622d97017053c6792382469d7dc26a486 (diff) | |
| download | linux-0cabb47af3cfaeb6007ba3868379bbd4daee64cc.tar.gz linux-0cabb47af3cfaeb6007ba3868379bbd4daee64cc.tar.bz2 linux-0cabb47af3cfaeb6007ba3868379bbd4daee64cc.zip | |
rcu: Refactor rcu_barrier() empty-list handling
This commit saves a few lines by checking first for an empty callback
list. If the callback list is empty, then that CPU is taken care of,
regardless of its online or nocb state. Also simplify tracing accordingly
and fold a few lines together.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu/tree.c')
| -rw-r--r-- | kernel/rcu/tree.c | 25 |
1 files changed, 8 insertions, 17 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 73a4c9d07b86..57a7a0065750 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -4030,8 +4030,7 @@ void rcu_barrier(void) /* Did someone else do our work for us? */ if (rcu_seq_done(&rcu_state.barrier_sequence, s)) { - rcu_barrier_trace(TPS("EarlyExit"), -1, - rcu_state.barrier_sequence); + rcu_barrier_trace(TPS("EarlyExit"), -1, rcu_state.barrier_sequence); smp_mb(); /* caller's subsequent code after above check. */ mutex_unlock(&rcu_state.barrier_mutex); return; @@ -4059,26 +4058,18 @@ void rcu_barrier(void) */ for_each_possible_cpu(cpu) { rdp = per_cpu_ptr(&rcu_data, cpu); - if (cpu_is_offline(cpu) && - !rcu_rdp_is_offloaded(rdp)) + if (!rcu_segcblist_n_cbs(&rdp->cblist)) { + rcu_barrier_trace(TPS("NQ"), cpu, rcu_state.barrier_sequence); continue; - if (rcu_segcblist_n_cbs(&rdp->cblist) && cpu_online(cpu)) { - rcu_barrier_trace(TPS("OnlineQ"), cpu, - rcu_state.barrier_sequence); + } + if (cpu_online(cpu)) { + rcu_barrier_trace(TPS("OnlineQ"), cpu, rcu_state.barrier_sequence); smp_call_function_single(cpu, rcu_barrier_func, (void *)cpu, 1); - } else if (rcu_segcblist_n_cbs(&rdp->cblist) && - cpu_is_offline(cpu)) { - rcu_barrier_trace(TPS("OfflineNoCBQ"), cpu, - rcu_state.barrier_sequence); + } else { + rcu_barrier_trace(TPS("OfflineNoCBQ"), cpu, rcu_state.barrier_sequence); local_irq_disable(); rcu_barrier_func((void *)cpu); local_irq_enable(); - } else if (cpu_is_offline(cpu)) { - rcu_barrier_trace(TPS("OfflineNoCBNoQ"), cpu, - rcu_state.barrier_sequence); - } else { - rcu_barrier_trace(TPS("OnlineNQ"), cpu, - rcu_state.barrier_sequence); } } cpus_read_unlock(); |