cpuset: refactor cpuset_hotplug_update_tasks()

We mix the handling for both default hierarchy and legacy hierarchy in
the same function, and it's quite messy, so split into two functions.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Li Zefan 2014-07-09 16:48:54 +08:00 committed by Tejun Heo
parent 7e88291bee
commit 390a36aadf

View File

@ -2080,6 +2080,65 @@ static void remove_tasks_in_empty_cpuset(struct cpuset *cs)
}
}
static void hotplug_update_tasks_legacy(struct cpuset *cs,
struct cpumask *off_cpus,
nodemask_t *off_mems)
{
bool is_empty;
mutex_lock(&callback_mutex);
cpumask_andnot(cs->cpus_allowed, cs->cpus_allowed, off_cpus);
cpumask_andnot(cs->effective_cpus, cs->effective_cpus, off_cpus);
nodes_andnot(cs->mems_allowed, cs->mems_allowed, *off_mems);
nodes_andnot(cs->effective_mems, cs->effective_mems, *off_mems);
mutex_unlock(&callback_mutex);
/*
* Don't call update_tasks_cpumask() if the cpuset becomes empty,
* as the tasks will be migratecd to an ancestor.
*/
if (!cpumask_empty(off_cpus) && !cpumask_empty(cs->cpus_allowed))
update_tasks_cpumask(cs);
if (!nodes_empty(*off_mems) && !nodes_empty(cs->mems_allowed))
update_tasks_nodemask(cs);
is_empty = cpumask_empty(cs->cpus_allowed) ||
nodes_empty(cs->mems_allowed);
mutex_unlock(&cpuset_mutex);
/*
* Move tasks to the nearest ancestor with execution resources,
* This is full cgroup operation which will also call back into
* cpuset. Should be done outside any lock.
*/
if (is_empty)
remove_tasks_in_empty_cpuset(cs);
mutex_lock(&cpuset_mutex);
}
static void hotplug_update_tasks(struct cpuset *cs,
struct cpumask *off_cpus,
nodemask_t *off_mems)
{
mutex_lock(&callback_mutex);
cpumask_andnot(cs->effective_cpus, cs->effective_cpus, off_cpus);
if (cpumask_empty(cs->effective_cpus))
cpumask_copy(cs->effective_cpus,
parent_cs(cs)->effective_cpus);
nodes_andnot(cs->effective_mems, cs->effective_mems, *off_mems);
if (nodes_empty(cs->effective_mems))
cs->effective_mems = parent_cs(cs)->effective_mems;
mutex_unlock(&callback_mutex);
if (!cpumask_empty(off_cpus))
update_tasks_cpumask(cs);
if (!nodes_empty(*off_mems))
update_tasks_nodemask(cs);
}
/**
* cpuset_hotplug_update_tasks - update tasks in a cpuset for hotunplug
* @cs: cpuset in interest
@ -2092,9 +2151,6 @@ static void cpuset_hotplug_update_tasks(struct cpuset *cs)
{
static cpumask_t off_cpus;
static nodemask_t off_mems;
bool is_empty;
bool on_dfl = cgroup_on_dfl(cs->css.cgroup);
retry:
wait_event(cpuset_attach_wq, cs->attach_in_progress == 0);
@ -2109,61 +2165,16 @@ static void cpuset_hotplug_update_tasks(struct cpuset *cs)
goto retry;
}
cpumask_andnot(&off_cpus, cs->cpus_allowed, top_cpuset.cpus_allowed);
nodes_andnot(off_mems, cs->mems_allowed, top_cpuset.mems_allowed);
cpumask_andnot(&off_cpus, cs->effective_cpus,
top_cpuset.effective_cpus);
nodes_andnot(off_mems, cs->effective_mems, top_cpuset.effective_mems);
mutex_lock(&callback_mutex);
cpumask_andnot(cs->cpus_allowed, cs->cpus_allowed, &off_cpus);
/* Inherit the effective mask of the parent, if it becomes empty. */
cpumask_andnot(cs->effective_cpus, cs->effective_cpus, &off_cpus);
if (on_dfl && cpumask_empty(cs->effective_cpus))
cpumask_copy(cs->effective_cpus, parent_cs(cs)->effective_cpus);
mutex_unlock(&callback_mutex);
/*
* If on_dfl, we need to update tasks' cpumask for empty cpuset to
* take on ancestor's cpumask. Otherwise, don't call
* update_tasks_cpumask() if the cpuset becomes empty, as the tasks
* in it will be migrated to an ancestor.
*/
if ((on_dfl && cpumask_empty(cs->cpus_allowed)) ||
(!cpumask_empty(&off_cpus) && !cpumask_empty(cs->cpus_allowed)))
update_tasks_cpumask(cs);
mutex_lock(&callback_mutex);
nodes_andnot(cs->mems_allowed, cs->mems_allowed, off_mems);
/* Inherit the effective mask of the parent, if it becomes empty */
nodes_andnot(cs->effective_mems, cs->effective_mems, off_mems);
if (on_dfl && nodes_empty(cs->effective_mems))
cs->effective_mems = parent_cs(cs)->effective_mems;
mutex_unlock(&callback_mutex);
/*
* If on_dfl, we need to update tasks' nodemask for empty cpuset to
* take on ancestor's nodemask. Otherwise, don't call
* update_tasks_nodemask() if the cpuset becomes empty, as the
* tasks in it will be migratd to an ancestor.
*/
if ((on_dfl && nodes_empty(cs->mems_allowed)) ||
(!nodes_empty(off_mems) && !nodes_empty(cs->mems_allowed)))
update_tasks_nodemask(cs);
is_empty = cpumask_empty(cs->cpus_allowed) ||
nodes_empty(cs->mems_allowed);
if (cgroup_on_dfl(cs->css.cgroup))
hotplug_update_tasks(cs, &off_cpus, &off_mems);
else
hotplug_update_tasks_legacy(cs, &off_cpus, &off_mems);
mutex_unlock(&cpuset_mutex);
/*
* If on_dfl, we'll keep tasks in empty cpusets.
*
* Otherwise move tasks to the nearest ancestor with execution
* resources. This is full cgroup operation which will
* also call back into cpuset. Should be done outside any lock.
*/
if (!on_dfl && is_empty)
remove_tasks_in_empty_cpuset(cs);
}
/**