diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cgroup/cpuset.c | 53 |
1 files changed, 30 insertions, 23 deletions
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index f7efa7b4d825a..cab5fd1ee7671 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -812,6 +812,18 @@ done: return ndoms; } +static void cpuset_sched_change_begin(void) +{ + cpus_read_lock(); + mutex_lock(&cpuset_mutex); +} + +static void cpuset_sched_change_end(void) +{ + mutex_unlock(&cpuset_mutex); + cpus_read_unlock(); +} + /* * Rebuild scheduler domains. * @@ -821,16 +833,14 @@ 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_cpuslocked(void) { struct sched_domain_attr *attr; cpumask_var_t *doms; int ndoms; lockdep_assert_held(&cpuset_mutex); - get_online_cpus(); /* * We have raced with CPU hotplug. Don't do anything to avoid @@ -838,27 +848,25 @@ 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_cpuslocked(void) { } #endif /* CONFIG_SMP */ void rebuild_sched_domains(void) { - mutex_lock(&cpuset_mutex); - rebuild_sched_domains_locked(); - mutex_unlock(&cpuset_mutex); + cpuset_sched_change_begin(); + rebuild_sched_domains_cpuslocked(); + cpuset_sched_change_end(); } /** @@ -944,7 +952,7 @@ 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_cpuslocked(); } /** @@ -1276,7 +1284,7 @@ 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_cpuslocked(); } return 0; @@ -1309,7 +1317,6 @@ static void update_tasks_flags(struct cpuset *cs) * * Call with cpuset_mutex held. */ - static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, int turning_on) { @@ -1342,7 +1349,7 @@ 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_cpuslocked(); if (spread_flag_changed) update_tasks_flags(cs); @@ -1610,7 +1617,7 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft, cpuset_filetype_t type = cft->private; int retval = 0; - mutex_lock(&cpuset_mutex); + cpuset_sched_change_begin(); if (!is_cpuset_online(cs)) { retval = -ENODEV; goto out_unlock; @@ -1646,7 +1653,7 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft, break; } out_unlock: - mutex_unlock(&cpuset_mutex); + cpuset_sched_change_end(); return retval; } @@ -1657,7 +1664,7 @@ static int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft, cpuset_filetype_t type = cft->private; int retval = -ENODEV; - mutex_lock(&cpuset_mutex); + cpuset_sched_change_begin(); if (!is_cpuset_online(cs)) goto out_unlock; @@ -1670,7 +1677,7 @@ static int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft, break; } out_unlock: - mutex_unlock(&cpuset_mutex); + cpuset_sched_change_end(); return retval; } @@ -1709,7 +1716,7 @@ static ssize_t cpuset_write_resmask(struct kernfs_open_file *of, kernfs_break_active_protection(of->kn); flush_work(&cpuset_hotplug_work); - mutex_lock(&cpuset_mutex); + cpuset_sched_change_begin(); if (!is_cpuset_online(cs)) goto out_unlock; @@ -1733,7 +1740,7 @@ static ssize_t cpuset_write_resmask(struct kernfs_open_file *of, free_trial_cpuset(trialcs); out_unlock: - mutex_unlock(&cpuset_mutex); + cpuset_sched_change_end(); kernfs_unbreak_active_protection(of->kn); css_put(&cs->css); flush_workqueue(cpuset_migrate_mm_wq); @@ -2034,14 +2041,14 @@ 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_cpuslocked(). */ static void cpuset_css_offline(struct cgroup_subsys_state *css) { struct cpuset *cs = css_cs(css); - mutex_lock(&cpuset_mutex); + cpuset_sched_change_begin(); if (is_sched_load_balance(cs)) update_flag(CS_SCHED_LOAD_BALANCE, cs, 0); @@ -2049,7 +2056,7 @@ static void cpuset_css_offline(struct cgroup_subsys_state *css) cpuset_dec(); clear_bit(CS_ONLINE, &cs->flags); - mutex_unlock(&cpuset_mutex); + cpuset_sched_change_end(); } static void cpuset_css_free(struct cgroup_subsys_state *css) |