From 9e10a130d9b62af976d17d120c95f3650769312c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 18 Sep 2015 11:56:28 -0400 Subject: cgroup: replace cgroup_on_dfl() tests in controllers with cgroup_subsys_on_dfl() cgroup_on_dfl() tests whether the cgroup's root is the default hierarchy; however, an individual controller is only interested in whether the controller is attached to the default hierarchy and never tests a cgroup which doesn't belong to the hierarchy that the controller is attached to. This patch replaces cgroup_on_dfl() tests in controllers with faster static_key based cgroup_subsys_on_dfl(). This leaves cgroup core as the only user of cgroup_on_dfl() and the function is moved from the header file to cgroup.c. Signed-off-by: Tejun Heo Acked-by: Zefan Li Cc: Vivek Goyal Cc: Jens Axboe Cc: Johannes Weiner Cc: Michal Hocko --- kernel/cpuset.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) (limited to 'kernel/cpuset.c') diff --git a/kernel/cpuset.c b/kernel/cpuset.c index f0acff0f66c9..20eedd8098c0 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -473,7 +473,8 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial) /* On legacy hiearchy, we must be a subset of our parent cpuset. */ ret = -EACCES; - if (!cgroup_on_dfl(cur->css.cgroup) && !is_cpuset_subset(trial, par)) + if (!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && + !is_cpuset_subset(trial, par)) goto out; /* @@ -879,7 +880,8 @@ static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus) * If it becomes empty, inherit the effective mask of the * parent, which is guaranteed to have some CPUs. */ - if (cgroup_on_dfl(cp->css.cgroup) && cpumask_empty(new_cpus)) + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && + cpumask_empty(new_cpus)) cpumask_copy(new_cpus, parent->effective_cpus); /* Skip the whole subtree if the cpumask remains the same. */ @@ -896,7 +898,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus) cpumask_copy(cp->effective_cpus, new_cpus); spin_unlock_irq(&callback_lock); - WARN_ON(!cgroup_on_dfl(cp->css.cgroup) && + WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && !cpumask_equal(cp->cpus_allowed, cp->effective_cpus)); update_tasks_cpumask(cp); @@ -1135,7 +1137,8 @@ static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems) * If it becomes empty, inherit the effective mask of the * parent, which is guaranteed to have some MEMs. */ - if (cgroup_on_dfl(cp->css.cgroup) && nodes_empty(*new_mems)) + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && + nodes_empty(*new_mems)) *new_mems = parent->effective_mems; /* Skip the whole subtree if the nodemask remains the same. */ @@ -1152,7 +1155,7 @@ static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems) cp->effective_mems = *new_mems; spin_unlock_irq(&callback_lock); - WARN_ON(!cgroup_on_dfl(cp->css.cgroup) && + WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && !nodes_equal(cp->mems_allowed, cp->effective_mems)); update_tasks_nodemask(cp); @@ -1440,7 +1443,7 @@ static int cpuset_can_attach(struct cgroup_subsys_state *css, /* allow moving tasks into an empty cpuset if on default hierarchy */ ret = -ENOSPC; - if (!cgroup_on_dfl(css->cgroup) && + if (!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))) goto out_unlock; @@ -1952,7 +1955,7 @@ static int cpuset_css_online(struct cgroup_subsys_state *css) cpuset_inc(); spin_lock_irq(&callback_lock); - if (cgroup_on_dfl(cs->css.cgroup)) { + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) { cpumask_copy(cs->effective_cpus, parent->effective_cpus); cs->effective_mems = parent->effective_mems; } @@ -2029,7 +2032,7 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css) mutex_lock(&cpuset_mutex); spin_lock_irq(&callback_lock); - if (cgroup_on_dfl(root_css->cgroup)) { + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) { cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask); top_cpuset.mems_allowed = node_possible_map; } else { @@ -2210,7 +2213,7 @@ retry: cpus_updated = !cpumask_equal(&new_cpus, cs->effective_cpus); mems_updated = !nodes_equal(new_mems, cs->effective_mems); - if (cgroup_on_dfl(cs->css.cgroup)) + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) hotplug_update_tasks(cs, &new_cpus, &new_mems, cpus_updated, mems_updated); else @@ -2241,7 +2244,7 @@ static void cpuset_hotplug_workfn(struct work_struct *work) static cpumask_t new_cpus; static nodemask_t new_mems; bool cpus_updated, mems_updated; - bool on_dfl = cgroup_on_dfl(top_cpuset.css.cgroup); + bool on_dfl = cgroup_subsys_on_dfl(cpuset_cgrp_subsys); mutex_lock(&cpuset_mutex); -- cgit v1.2.3