cpuset: don't use cgroup_taskset_cur_css()
cgroup_taskset_cur_css() will be removed during the planned
resturcturing of migration path. The only use of
cgroup_taskset_cur_css() is finding out the old cgroup_subsys_state of
the leader in cpuset_attach(). This usage can easily be removed by
remembering the old value from cpuset_can_attach().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index bf20e4a..d8bec21 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1379,6 +1379,8 @@
return val;
}
+static struct cpuset *cpuset_attach_old_cs;
+
/* Called by cgroups to determine if a cpuset is usable; cpuset_mutex held */
static int cpuset_can_attach(struct cgroup_subsys_state *css,
struct cgroup_taskset *tset)
@@ -1387,6 +1389,9 @@
struct task_struct *task;
int ret;
+ /* used later by cpuset_attach() */
+ cpuset_attach_old_cs = task_cs(cgroup_taskset_first(tset));
+
mutex_lock(&cpuset_mutex);
/*
@@ -1450,10 +1455,8 @@
struct mm_struct *mm;
struct task_struct *task;
struct task_struct *leader = cgroup_taskset_first(tset);
- struct cgroup_subsys_state *oldcss = cgroup_taskset_cur_css(tset,
- cpuset_cgrp_id);
struct cpuset *cs = css_cs(css);
- struct cpuset *oldcs = css_cs(oldcss);
+ struct cpuset *oldcs = cpuset_attach_old_cs;
struct cpuset *cpus_cs = effective_cpumask_cpuset(cs);
struct cpuset *mems_cs = effective_nodemask_cpuset(cs);