diff options
| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2014-07-01 11:26:57 -0700 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2014-09-07 16:27:20 -0700 |
| commit | bde6c3aa993066acb0d6ce32ecabe03b9d5df92d (patch) | |
| tree | 09ec78a9cfa751ce36288c32c4e5112f34af8582 /kernel/rcu/tree_plugin.h | |
| parent | 8315f42295d2667a7f942f154b73a86fd7cb2227 (diff) | |
rcu: Provide cond_resched_rcu_qs() to force quiescent states in long loops
RCU-tasks requires the occasional voluntary context switch
from CPU-bound in-kernel tasks. In some cases, this requires
instrumenting cond_resched(). However, there is some reluctance
to countenance unconditionally instrumenting cond_resched() (see
http://lwn.net/Articles/603252/), so this commit creates a separate
cond_resched_rcu_qs() that may be used in place of cond_resched() in
locations prone to long-duration in-kernel looping.
This commit currently instruments only RCU-tasks. Future possibilities
include also instrumenting RCU, RCU-bh, and RCU-sched in order to reduce
IPI usage.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcu/tree_plugin.h')
| -rw-r--r-- | kernel/rcu/tree_plugin.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index a7997e272564..7672586d3920 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -1848,7 +1848,7 @@ static int rcu_oom_notify(struct notifier_block *self, get_online_cpus(); for_each_online_cpu(cpu) { smp_call_function_single(cpu, rcu_oom_notify_cpu, NULL, 1); - cond_resched(); + cond_resched_rcu_qs(); } put_online_cpus(); |