With the latest changes in sched/isolation.c, rebuild_sched_domains*()
requires the HK_TYPE_DOMAIN housekeeping cpumask to be properly
updated first, if needed, before the sched domains can be
rebuilt. So the two naturally fit together. Do that by creating a new
update_hk_sched_domains() helper to house both actions.
The name of the isolated_cpus_updating flag to control the
call to housekeeping_update() is now outdated. So change it to
update_housekeeping to better reflect its purpose. Also move the call
to update_hk_sched_domains() to the end of cpuset and hotplug operations
before releasing the cpuset_mutex.
Signed-off-by: Waiman Long <longman@redhat.com>
---
kernel/cgroup/cpuset.c | 51 ++++++++++++++++++++----------------------
1 file changed, 24 insertions(+), 27 deletions(-)
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 05adf6697030..3d0d18bf182f 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -130,10 +130,9 @@ static cpumask_var_t subpartitions_cpus; /* RWCS */
static cpumask_var_t isolated_cpus; /* CSCB */
/*
- * Set if isolated_cpus is being updated in the current cpuset_mutex
- * critical section.
+ * Set if housekeeping cpumasks are to be updated.
*/
-static bool isolated_cpus_updating; /* RWCS */
+static bool update_housekeeping; /* RWCS */
/*
* A flag to force sched domain rebuild at the end of an operation.
@@ -1188,7 +1187,7 @@ static void isolated_cpus_update(int old_prs, int new_prs, struct cpumask *xcpus
return;
cpumask_andnot(isolated_cpus, isolated_cpus, xcpus);
}
- isolated_cpus_updating = true;
+ update_housekeeping = true;
}
/*
@@ -1306,22 +1305,22 @@ static bool prstate_housekeeping_conflict(int prstate, struct cpumask *new_cpus)
}
/*
- * update_isolation_cpumasks - Update external isolation related CPU masks
+ * update_hk_sched_domains - Update HK cpumasks & rebuild sched domains
*
- * The following external CPU masks will be updated if necessary:
- * - workqueue unbound cpumask
+ * Update housekeeping cpumasks and rebuild sched domains if necessary.
+ * This should be called at the end of cpuset or hotplug actions.
*/
-static void update_isolation_cpumasks(void)
+static void update_hk_sched_domains(void)
{
- int ret;
-
- if (!isolated_cpus_updating)
- return;
-
- ret = housekeeping_update(isolated_cpus);
- WARN_ON_ONCE(ret < 0);
-
- isolated_cpus_updating = false;
+ if (update_housekeeping) {
+ /* Updating HK cpumasks implies rebuild sched domains */
+ WARN_ON_ONCE(housekeeping_update(isolated_cpus));
+ update_housekeeping = false;
+ force_sd_rebuild = true;
+ }
+ /* force_sd_rebuild will be cleared in rebuild_sched_domains_locked() */
+ if (force_sd_rebuild)
+ rebuild_sched_domains_locked();
}
/**
@@ -1472,7 +1471,6 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
cs->remote_partition = true;
cpumask_copy(cs->effective_xcpus, tmp->new_cpus);
spin_unlock_irq(&callback_lock);
- update_isolation_cpumasks();
cpuset_force_rebuild();
cs->prs_err = 0;
@@ -1517,7 +1515,6 @@ static void remote_partition_disable(struct cpuset *cs, struct tmpmasks *tmp)
compute_excpus(cs, cs->effective_xcpus);
reset_partition_data(cs);
spin_unlock_irq(&callback_lock);
- update_isolation_cpumasks();
cpuset_force_rebuild();
/*
@@ -1588,7 +1585,6 @@ static void remote_cpus_update(struct cpuset *cs, struct cpumask *xcpus,
if (xcpus)
cpumask_copy(cs->exclusive_cpus, xcpus);
spin_unlock_irq(&callback_lock);
- update_isolation_cpumasks();
if (adding || deleting)
cpuset_force_rebuild();
@@ -1932,7 +1928,6 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd,
partition_xcpus_add(new_prs, parent, tmp->delmask);
spin_unlock_irq(&callback_lock);
- update_isolation_cpumasks();
if ((old_prs != new_prs) && (cmd == partcmd_update))
update_partition_exclusive_flag(cs, new_prs);
@@ -2900,7 +2895,6 @@ static int update_prstate(struct cpuset *cs, int new_prs)
else if (isolcpus_updated)
isolated_cpus_update(old_prs, new_prs, cs->effective_xcpus);
spin_unlock_irq(&callback_lock);
- update_isolation_cpumasks();
/* Force update if switching back to member & update effective_xcpus */
update_cpumasks_hier(cs, &tmpmask, !new_prs);
@@ -3190,9 +3184,8 @@ ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
}
free_cpuset(trialcs);
- if (force_sd_rebuild)
- rebuild_sched_domains_locked();
out_unlock:
+ update_hk_sched_domains();
cpuset_full_unlock();
if (of_cft(of)->private == FILE_MEMLIST)
schedule_flush_migrate_mm();
@@ -3300,6 +3293,7 @@ static ssize_t cpuset_partition_write(struct kernfs_open_file *of, char *buf,
cpuset_full_lock();
if (is_cpuset_online(cs))
retval = update_prstate(cs, val);
+ update_hk_sched_domains();
cpuset_full_unlock();
return retval ?: nbytes;
}
@@ -3474,6 +3468,7 @@ static void cpuset_css_killed(struct cgroup_subsys_state *css)
/* Reset valid partition back to member */
if (is_partition_valid(cs))
update_prstate(cs, PRS_MEMBER);
+ update_hk_sched_domains();
cpuset_full_unlock();
}
@@ -3881,10 +3876,12 @@ static void cpuset_handle_hotplug(void)
rcu_read_unlock();
}
- /* rebuild sched domains if necessary */
- if (force_sd_rebuild)
- rebuild_sched_domains_cpuslocked();
+ if (update_housekeeping || force_sd_rebuild) {
+ mutex_lock(&cpuset_mutex);
+ update_hk_sched_domains();
+ mutex_unlock(&cpuset_mutex);
+ }
free_tmpmasks(ptmp);
}
--
2.53.0