diff options
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 7 | ||||
| -rw-r--r-- | kernel/rcu/tasks.h | 7 |
2 files changed, 12 insertions, 2 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a0f427e1a562..44705a3618b9 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5264,6 +5264,13 @@ number avoids disturbing real-time workloads, but lengthens grace periods. + rcupdate.rcu_task_lazy_lim= [KNL] + Number of callbacks on a given CPU that will + cancel laziness on that CPU. Use -1 to disable + cancellation of laziness, but be advised that + doing so increases the danger of OOM due to + callback flooding. + rcupdate.rcu_task_stall_info= [KNL] Set initial timeout in jiffies for RCU task stall informational messages, which give some indication diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index 28e986627e3f..291d536b1789 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -176,6 +176,8 @@ static int rcu_task_contend_lim __read_mostly = 100; module_param(rcu_task_contend_lim, int, 0444); static int rcu_task_collapse_lim __read_mostly = 10; module_param(rcu_task_collapse_lim, int, 0444); +static int rcu_task_lazy_lim __read_mostly = 32; +module_param(rcu_task_lazy_lim, int, 0444); /* RCU tasks grace-period state for debugging. */ #define RTGS_INIT 0 @@ -354,8 +356,9 @@ static void call_rcu_tasks_generic(struct rcu_head *rhp, rcu_callback_t func, cblist_init_generic(rtp); raw_spin_lock_rcu_node(rtpcp); // irqs already disabled. } - needwake = func == wakeme_after_rcu; - if (havekthread && !timer_pending(&rtpcp->lazy_timer)) { + needwake = (func == wakeme_after_rcu) || + (rcu_segcblist_n_cbs(&rtpcp->cblist) == rcu_task_lazy_lim); + if (havekthread && !needwake && !timer_pending(&rtpcp->lazy_timer)) { if (rtp->lazy_jiffies) mod_timer(&rtpcp->lazy_timer, rcu_tasks_lazy_time(rtp)); else |