rcu/nocb: Rename rcu_nocb_leader_stride kernel boot parameter

This commit changes the name of the rcu_nocb_leader_stride kernel
boot parameter to rcu_nocb_gp_stride in order to account for the new
distinction between callback and grace-period no-CBs kthreads.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit is contained in:
Paul E. McKenney 2019-04-02 08:05:55 -07:00
parent f7c9a9b664
commit f7c612b000
2 changed files with 11 additions and 10 deletions

View File

@ -3837,12 +3837,13 @@
RCU_BOOST is not set, valid values are 0-99 and
the default is zero (non-realtime operation).
rcutree.rcu_nocb_leader_stride= [KNL]
Set the number of NOCB kthread groups, which
defaults to the square root of the number of
CPUs. Larger numbers reduces the wakeup overhead
on the per-CPU grace-period kthreads, but increases
that same overhead on each group's leader.
rcutree.rcu_nocb_gp_stride= [KNL]
Set the number of NOCB callback kthreads in
each group, which defaults to the square root
of the number of CPUs. Larger numbers reduce
the wakeup overhead on the global grace-period
kthread, but increases that same overhead on
each group's NOCB grace-period kthread.
rcutree.qhimark= [KNL]
Set threshold of queued RCU callbacks beyond which

View File

@ -2126,8 +2126,8 @@ static void __init rcu_spawn_nocb_kthreads(void)
}
/* How many CB CPU IDs per GP kthread? Default of -1 for sqrt(nr_cpu_ids). */
static int rcu_nocb_leader_stride = -1;
module_param(rcu_nocb_leader_stride, int, 0444);
static int rcu_nocb_gp_stride = -1;
module_param(rcu_nocb_gp_stride, int, 0444);
/*
* Initialize GP-CB relationships for all no-CBs CPU.
@ -2135,7 +2135,7 @@ module_param(rcu_nocb_leader_stride, int, 0444);
static void __init rcu_organize_nocb_kthreads(void)
{
int cpu;
int ls = rcu_nocb_leader_stride;
int ls = rcu_nocb_gp_stride;
int nl = 0; /* Next GP kthread. */
struct rcu_data *rdp;
struct rcu_data *rdp_gp = NULL; /* Suppress misguided gcc warn. */
@ -2145,7 +2145,7 @@ static void __init rcu_organize_nocb_kthreads(void)
return;
if (ls == -1) {
ls = int_sqrt(nr_cpu_ids);
rcu_nocb_leader_stride = ls;
rcu_nocb_gp_stride = ls;
}
/*