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Diffstat (limited to 'kernel/cpuset.c')
-rw-r--r--kernel/cpuset.c54
1 files changed, 30 insertions, 24 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 3190ef04e033..2ce1a5297b92 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -99,7 +99,7 @@ struct cpuset {
/* user-configured CPUs and Memory Nodes allow to tasks */
cpumask_var_t cpus_allowed;
- cpumask_var_t cpus_requested;
+ cpumask_var_t cpus_requested; /* CPUS requested, but not used because of hotplug */
nodemask_t mems_allowed;
/* effective CPUs and Memory Nodes allow to tasks */
@@ -813,16 +813,15 @@ done:
* 'cpus' is removed, then call this routine to rebuild the
* scheduler's dynamic sched domains.
*
- * Call with cpuset_mutex held. Takes get_online_cpus().
*/
-static void rebuild_sched_domains_locked(void)
+static void rebuild_sched_domains_unlocked(void)
{
struct sched_domain_attr *attr;
cpumask_var_t *doms;
int ndoms;
+ cpu_hotplug_mutex_held();
lockdep_assert_held(&cpuset_mutex);
- get_online_cpus();
/*
* We have raced with CPU hotplug. Don't do anything to avoid
@@ -830,27 +829,27 @@ static void rebuild_sched_domains_locked(void)
* Anyways, hotplug work item will rebuild sched domains.
*/
if (!cpumask_equal(top_cpuset.effective_cpus, cpu_active_mask))
- goto out;
+ return;
/* Generate domain masks and attrs */
ndoms = generate_sched_domains(&doms, &attr);
/* Have scheduler rebuild the domains */
partition_sched_domains(ndoms, doms, attr);
-out:
- put_online_cpus();
}
#else /* !CONFIG_SMP */
-static void rebuild_sched_domains_locked(void)
+static void rebuild_sched_domains_unlocked(void)
{
}
#endif /* CONFIG_SMP */
void rebuild_sched_domains(void)
{
+ get_online_cpus();
mutex_lock(&cpuset_mutex);
- rebuild_sched_domains_locked();
+ rebuild_sched_domains_unlocked();
mutex_unlock(&cpuset_mutex);
+ put_online_cpus();
}
/**
@@ -882,7 +881,6 @@ static void update_tasks_cpumask(struct cpuset *cs)
*
* On legacy hierachy, effective_cpus will be the same with cpu_allowed.
*
- * Called with cpuset_mutex held
*/
static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus)
{
@@ -937,7 +935,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus)
rcu_read_unlock();
if (need_rebuild_sched_domains)
- rebuild_sched_domains_locked();
+ rebuild_sched_domains_unlocked();
}
/**
@@ -1296,7 +1294,7 @@ static int update_relax_domain_level(struct cpuset *cs, s64 val)
cs->relax_domain_level = val;
if (!cpumask_empty(cs->cpus_allowed) &&
is_sched_load_balance(cs))
- rebuild_sched_domains_locked();
+ rebuild_sched_domains_unlocked();
}
return 0;
@@ -1327,7 +1325,6 @@ static void update_tasks_flags(struct cpuset *cs)
* cs: the cpuset to update
* turning_on: whether the flag is being set or cleared
*
- * Call with cpuset_mutex held.
*/
static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
@@ -1362,7 +1359,7 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
spin_unlock_irq(&callback_lock);
if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed)
- rebuild_sched_domains_locked();
+ rebuild_sched_domains_unlocked();
if (spread_flag_changed)
update_tasks_flags(cs);
@@ -1627,6 +1624,7 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft,
cpuset_filetype_t type = cft->private;
int retval = 0;
+ get_online_cpus();
mutex_lock(&cpuset_mutex);
if (!is_cpuset_online(cs)) {
retval = -ENODEV;
@@ -1664,6 +1662,7 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft,
}
out_unlock:
mutex_unlock(&cpuset_mutex);
+ put_online_cpus();
return retval;
}
@@ -1674,6 +1673,7 @@ static int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
cpuset_filetype_t type = cft->private;
int retval = -ENODEV;
+ get_online_cpus();
mutex_lock(&cpuset_mutex);
if (!is_cpuset_online(cs))
goto out_unlock;
@@ -1688,6 +1688,7 @@ static int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
}
out_unlock:
mutex_unlock(&cpuset_mutex);
+ put_online_cpus();
return retval;
}
@@ -1726,6 +1727,7 @@ static ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
kernfs_break_active_protection(of->kn);
flush_work(&cpuset_hotplug_work);
+ get_online_cpus();
mutex_lock(&cpuset_mutex);
if (!is_cpuset_online(cs))
goto out_unlock;
@@ -1751,6 +1753,7 @@ static ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
free_trial_cpuset(trialcs);
out_unlock:
mutex_unlock(&cpuset_mutex);
+ put_online_cpus();
kernfs_unbreak_active_protection(of->kn);
css_put(&cs->css);
flush_workqueue(cpuset_migrate_mm_wq);
@@ -1964,11 +1967,11 @@ cpuset_css_alloc(struct cgroup_subsys_state *parent_css)
if (!cs)
return ERR_PTR(-ENOMEM);
if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL))
- goto free_cs;
- if (!alloc_cpumask_var(&cs->cpus_requested, GFP_KERNEL))
- goto free_allowed;
+ goto error_allowed;
if (!alloc_cpumask_var(&cs->effective_cpus, GFP_KERNEL))
- goto free_requested;
+ goto error_effective;
+ if (!alloc_cpumask_var(&cs->cpus_requested, GFP_KERNEL))
+ goto error_requested;
set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
cpumask_clear(cs->cpus_allowed);
@@ -1981,11 +1984,11 @@ cpuset_css_alloc(struct cgroup_subsys_state *parent_css)
return &cs->css;
-free_requested:
- free_cpumask_var(cs->cpus_requested);
-free_allowed:
+error_requested:
+ free_cpumask_var(cs->effective_cpus);
+error_effective:
free_cpumask_var(cs->cpus_allowed);
-free_cs:
+error_allowed:
kfree(cs);
return ERR_PTR(-ENOMEM);
}
@@ -2057,13 +2060,14 @@ out_unlock:
/*
* If the cpuset being removed has its flag 'sched_load_balance'
* enabled, then simulate turning sched_load_balance off, which
- * will call rebuild_sched_domains_locked().
+ * will call rebuild_sched_domains_unlocked().
*/
static void cpuset_css_offline(struct cgroup_subsys_state *css)
{
struct cpuset *cs = css_cs(css);
+ get_online_cpus();
mutex_lock(&cpuset_mutex);
if (is_sched_load_balance(cs))
@@ -2073,6 +2077,7 @@ static void cpuset_css_offline(struct cgroup_subsys_state *css)
clear_bit(CS_ONLINE, &cs->flags);
mutex_unlock(&cpuset_mutex);
+ put_online_cpus();
}
static void cpuset_css_free(struct cgroup_subsys_state *css)
@@ -2284,7 +2289,8 @@ retry:
goto retry;
}
- cpumask_and(&new_cpus, cs->cpus_requested, parent_cs(cs)->effective_cpus);
+ cpumask_and(&new_cpus, cs->cpus_requested,
+ parent_cs(cs)->effective_cpus);
nodes_and(new_mems, cs->mems_allowed, parent_cs(cs)->effective_mems);
cpus_updated = !cpumask_equal(&new_cpus, cs->effective_cpus);
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-23 14:17:10 +0000