[PATCH v2 -next 08/11] cgroup/cpuset: move validate_change_legacy to cpuset-v1.c

Chen Ridong
2024-08-26T13:34:55Z

The validate_change_legacy functions is used for v1, move it to
cpuset-v1.c. And two micro 'cpuset_for_each_child' and
'cpuset_for_each_descendant_pre' are common for v1 and v2, move them to
cpuset-internal.h.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
kernel/cgroup/cpuset-internal.h | 29 +++++++++++++
kernel/cgroup/cpuset-v1.c | 45 ++++++++++++++++++++
kernel/cgroup/cpuset.c | 73 ---------------------------------
3 files changed, 74 insertions(+), 73 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 7cd30ad809d5..07551ff0812e 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -238,6 +238,34 @@ static inline int is_spread_slab(const struct cpuset *cs)
return test_bit(CS_SPREAD_SLAB, &cs->flags);
}

+/**
+ * cpuset_for_each_child - traverse online children of a cpuset
+ * @child_cs: loop cursor pointing to the current child
+ * @pos_css: used for iteration
+ * @parent_cs: target cpuset to walk children of
+ *
+ * Walk @child_cs through the online children of @parent_cs. Must be used
+ * with RCU read locked.
+ */
+#define cpuset_for_each_child(child_cs, pos_css, parent_cs) \
+ css_for_each_child((pos_css), &(parent_cs)->css) \
+ if (is_cpuset_online(((child_cs) = css_cs((pos_css)))))
+
+/**
+ * cpuset_for_each_descendant_pre - pre-order walk of a cpuset's descendants
+ * @des_cs: loop cursor pointing to the current descendant
+ * @pos_css: used for iteration
+ * @root_cs: target cpuset to walk ancestor of
+ *
+ * Walk @des_cs through the online descendants of @root_cs. Must be used
+ * with RCU read locked. The caller may modify @pos_css by calling
+ * css_rightmost_descendant() to skip subtree. @root_cs is included in the
+ * iteration and the first node to be visited.
+ */
+#define cpuset_for_each_descendant_pre(des_cs, pos_css, root_cs) \
+ css_for_each_descendant_pre((pos_css), &(root_cs)->css) \
+ if (is_cpuset_online(((des_cs) = css_cs((pos_css)))))
+
void rebuild_sched_domains_locked(void);
void callback_lock_irq(void);
void callback_unlock_irq(void);
@@ -258,5 +286,6 @@ void update_tasks_flags(struct cpuset *cs);
void hotplug_update_tasks_legacy(struct cpuset *cs,
struct cpumask *new_cpus, nodemask_t *new_mems,
bool cpus_updated, bool mems_updated);
+int validate_change_legacy(struct cpuset *cur, struct cpuset *trial);

#endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
index ce1d00746e92..246fc962f549 100644
--- a/kernel/cgroup/cpuset-v1.c
+++ b/kernel/cgroup/cpuset-v1.c
@@ -328,3 +328,48 @@ void hotplug_update_tasks_legacy(struct cpuset *cs,
}
}

+/*
+ * is_cpuset_subset(p, q) - Is cpuset p a subset of cpuset q?
+ *
+ * One cpuset is a subset of another if all its allowed CPUs and
+ * Memory Nodes are a subset of the other, and its exclusive flags
+ * are only set if the other's are set. Call holding cpuset_mutex.
+ */
+
+static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q)
+{
+ return cpumask_subset(p->cpus_allowed, q->cpus_allowed) &&
+ nodes_subset(p->mems_allowed, q->mems_allowed) &&
+ is_cpu_exclusive(p) <= is_cpu_exclusive(q) &&
+ is_mem_exclusive(p) <= is_mem_exclusive(q);
+}
+
+/*
+ * validate_change_legacy() - Validate conditions specific to legacy (v1)
+ * behavior.
+ */
+int validate_change_legacy(struct cpuset *cur, struct cpuset *trial)
+{
+ struct cgroup_subsys_state *css;
+ struct cpuset *c, *par;
+ int ret;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ /* Each of our child cpusets must be a subset of us */
+ ret = -EBUSY;
+ cpuset_for_each_child(c, css, cur)
+ if (!is_cpuset_subset(c, trial))
+ goto out;
+
+ /* On legacy hierarchy, we must be a subset of our parent cpuset. */
+ ret = -EACCES;
+ par = parent_cs(cur);
+ if (par && !is_cpuset_subset(trial, par))
+ goto out;
+
+ ret = 0;
+out:
+ return ret;
+}
+
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index b93ef0b48eae..4412a4168902 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -180,34 +180,6 @@ static struct cpuset top_cpuset = {
.remote_sibling = LIST_HEAD_INIT(top_cpuset.remote_sibling),
};

-/**
- * cpuset_for_each_child - traverse online children of a cpuset
- * @child_cs: loop cursor pointing to the current child
- * @pos_css: used for iteration
- * @parent_cs: target cpuset to walk children of
- *
- * Walk @child_cs through the online children of @parent_cs. Must be used
- * with RCU read locked.
- */
-#define cpuset_for_each_child(child_cs, pos_css, parent_cs) \
- css_for_each_child((pos_css), &(parent_cs)->css) \
- if (is_cpuset_online(((child_cs) = css_cs((pos_css)))))
-
-/**
- * cpuset_for_each_descendant_pre - pre-order walk of a cpuset's descendants
- * @des_cs: loop cursor pointing to the current descendant
- * @pos_css: used for iteration
- * @root_cs: target cpuset to walk ancestor of
- *
- * Walk @des_cs through the online descendants of @root_cs. Must be used
- * with RCU read locked. The caller may modify @pos_css by calling
- * css_rightmost_descendant() to skip subtree. @root_cs is included in the
- * iteration and the first node to be visited.
- */
-#define cpuset_for_each_descendant_pre(des_cs, pos_css, root_cs) \
- css_for_each_descendant_pre((pos_css), &(root_cs)->css) \
- if (is_cpuset_online(((des_cs) = css_cs((pos_css)))))
-
/*
* There are two global locks guarding cpuset structures - cpuset_mutex and
* callback_lock. We also require taking task_lock() when dereferencing a
@@ -403,22 +375,6 @@ static void guarantee_online_mems(struct cpuset *cs, nodemask_t *pmask)
nodes_and(*pmask, cs->effective_mems, node_states[N_MEMORY]);
}

-/*
- * is_cpuset_subset(p, q) - Is cpuset p a subset of cpuset q?
- *
- * One cpuset is a subset of another if all its allowed CPUs and
- * Memory Nodes are a subset of the other, and its exclusive flags
- * are only set if the other's are set. Call holding cpuset_mutex.
- */
-
-static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q)
-{
- return cpumask_subset(p->cpus_allowed, q->cpus_allowed) &&
- nodes_subset(p->mems_allowed, q->mems_allowed) &&
- is_cpu_exclusive(p) <= is_cpu_exclusive(q) &&
- is_mem_exclusive(p) <= is_mem_exclusive(q);
-}
-
/**
* alloc_cpumasks - allocate three cpumasks for cpuset
* @cs: the cpuset that have cpumasks to be allocated.
@@ -549,35 +505,6 @@ static inline bool cpusets_are_exclusive(struct cpuset *cs1, struct cpuset *cs2)
return true;
}

-/*
- * validate_change_legacy() - Validate conditions specific to legacy (v1)
- * behavior.
- */
-static int validate_change_legacy(struct cpuset *cur, struct cpuset *trial)
-{
- struct cgroup_subsys_state *css;
- struct cpuset *c, *par;
- int ret;
-
- WARN_ON_ONCE(!rcu_read_lock_held());
-
- /* Each of our child cpusets must be a subset of us */
- ret = -EBUSY;
- cpuset_for_each_child(c, css, cur)
- if (!is_cpuset_subset(c, trial))
- goto out;
-
- /* On legacy hierarchy, we must be a subset of our parent cpuset. */
- ret = -EACCES;
- par = parent_cs(cur);
- if (par && !is_cpuset_subset(trial, par))
- goto out;
-
- ret = 0;
-out:
- return ret;
-}
-
/*
* validate_change() - Used to validate that any proposed cpuset change
* follows the structural rules for cpusets.
--
2.34.1