diff options
| author |   Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-07-26 13:44:00 -0700 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-08-30 16:03:45 -0700 |
| commit | fced9c8cfe6bc8a26dbbf785927aa673c83a7a35 (patch) | |
| tree | 04b80df17ce5b236c0aa4fef28a5d1ab6bf889b0 /kernel/rcu/tree_plugin.h | |
| parent | rcu: More aggressively enlist scheduler aid for nohz_full CPUs (diff) | |
| download | linux-dev-fced9c8cfe6bc8a26dbbf785927aa673c83a7a35.tar.xz linux-dev-fced9c8cfe6bc8a26dbbf785927aa673c83a7a35.zip | |
rcu: Avoid resched_cpu() when rescheduling the current CPU
The resched_cpu() interface is quite handy, but it does acquire the
specified CPU's runqueue lock, which does not come for free. This
commit therefore substitutes the following when directing resched_cpu()
at the current CPU:
set_tsk_need_resched(current);
set_preempt_need_resched();
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Diffstat (limited to 'kernel/rcu/tree_plugin.h')
| -rw-r--r-- | kernel/rcu/tree_plugin.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 1e80a0da7924..978ce3539809 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -791,8 +791,10 @@ static void rcu_flavor_check_callbacks(int user) if (t->rcu_read_lock_nesting > 0 || (preempt_count() & (PREEMPT_MASK | SOFTIRQ_MASK))) { /* No QS, force context switch if deferred. */ - if (rcu_preempt_need_deferred_qs(t)) - resched_cpu(smp_processor_id()); + if (rcu_preempt_need_deferred_qs(t)) { + set_tsk_need_resched(t); + set_preempt_need_resched(); + } } else if (rcu_preempt_need_deferred_qs(t)) { rcu_preempt_deferred_qs(t); /* Report deferred QS. */ return; |