diff options
Diffstat (limited to 'Documentation/admin-guide/kernel-parameters.txt')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index bdf431bdbfdc..40a05df05580 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4681,6 +4681,19 @@ invoked in the context of an rcuoc kthread, which scheduler will preempt as it does any other task. + rcutree.nocb_nobypass_lim_per_jiffy= [KNL] + On callback-offloaded (rcu_nocbs) CPUs, + RCU reduces the lock contention that would + otherwise be caused by callback floods through + use of the ->nocb_bypass list. However, in the + common non-flooded case, RCU queues directly to + the main ->cblist in order to avoid the extra + overhead of the ->nocb_bypass list and its lock. + But if there are too many callbacks queued during + a single jiffy, RCU pre-queues the callbacks into + the ->nocb_bypass queue. The definition of "too + many" is supplied by this kernel boot parameter. + rcutree.rcu_nocb_gp_stride= [KNL] Set the number of NOCB callback kthreads in each group, which defaults to the square root |