Since the cgroup_subsystem_state owns the rstat tree, the list management
previously done by the cgroup is no longer needed.
Signed-off-by: JP Kobryn <inwardvessel@xxxxxxxxx>
---
include/linux/cgroup-defs.h | 11 -----------
kernel/cgroup/cgroup.c | 20 +-------------------
kernel/cgroup/rstat.c | 9 +--------
3 files changed, 2 insertions(+), 38 deletions(-)
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 4d87519ff023..836260c422a0 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -182,14 +182,6 @@ struct cgroup_subsys_state {
/* per-cpu recursive resource statistics */
struct cgroup_rstat_cpu __percpu *rstat_cpu;
- struct list_head rstat_css_list;
-
- /*
- * Add padding to separate the read mostly rstat_cpu and
- * rstat_css_list into a different cacheline from the following
- * rstat_flush_next and *bstat fields which can have frequent updates.
- */
- CACHELINE_PADDING(_pad_);
/*
* A singly-linked list of cgroup structures to be rstat flushed.
@@ -198,9 +190,6 @@ struct cgroup_subsys_state {
*/
struct cgroup_subsys_state *rstat_flush_next;
- /* flush target list anchored at cgrp->rstat_css_list */
- struct list_head rstat_css_node;
-
/*
* PI: Subsys-unique ID. 0 is unused and root is always 1. The
* matching css can be looked up using css_from_id().
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 96a2d15fe5e9..a36ed3995c6f 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -1826,7 +1826,6 @@ int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask)
struct cgroup_root *src_root = ss->root;
struct cgroup *scgrp = &src_root->cgrp;
struct cgroup_subsys_state *css = cgroup_css(scgrp, ss);
- struct cgroup_subsys_state *dcss = cgroup_css(dcgrp, ss);
struct css_set *cset, *cset_pos;
struct css_task_iter *it;
@@ -1864,13 +1863,6 @@ int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask)
}
spin_unlock_irq(&css_set_lock);
- if (ss->css_rstat_flush) {
- list_del_rcu(&css->rstat_css_node);
- synchronize_rcu();
- list_add_rcu(&css->rstat_css_node,
- &dcss->rstat_css_list);
- }
-
/* default hierarchy doesn't enable controllers by default */
dst_root->subsys_mask |= 1 << ssid;
if (dst_root == &cgrp_dfl_root) {
@@ -5491,11 +5483,7 @@ static void css_release_work_fn(struct work_struct *work)
if (ss) {
struct cgroup *parent_cgrp;
- /* css release path */
- if (!list_empty(&css->rstat_css_node)) {
- cgroup_rstat_flush(css);
- list_del_rcu(&css->rstat_css_node);
- }
+ cgroup_rstat_flush(css);
cgroup_idr_replace(&ss->css_idr, NULL, css->id);
if (ss->css_released)
@@ -5569,8 +5557,6 @@ static void init_and_link_css(struct cgroup_subsys_state *css,
css->id = -1;
INIT_LIST_HEAD(&css->sibling);
INIT_LIST_HEAD(&css->children);
- INIT_LIST_HEAD(&css->rstat_css_list);
- INIT_LIST_HEAD(&css->rstat_css_node);
css->serial_nr = css_serial_nr_next++;
atomic_set(&css->online_cnt, 0);
@@ -5579,9 +5565,6 @@ static void init_and_link_css(struct cgroup_subsys_state *css,
css_get(css->parent);
}
- if (ss->css_rstat_flush)
- list_add_rcu(&css->rstat_css_node, &css->rstat_css_list);
-
BUG_ON(cgroup_css(cgrp, ss));
}
@@ -5687,7 +5670,6 @@ static struct cgroup_subsys_state *css_create(struct cgroup *cgrp,
err_list_del:
list_del_rcu(&css->sibling);
err_free_css:
- list_del_rcu(&css->rstat_css_node);
INIT_RCU_WORK(&css->destroy_rwork, css_free_rwork_fn);
queue_rcu_work(cgroup_destroy_wq, &css->destroy_rwork);
return ERR_PTR(err);
diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c
index 92a46b960be1..c52e8429c75d 100644
--- a/kernel/cgroup/rstat.c
+++ b/kernel/cgroup/rstat.c
@@ -347,15 +347,8 @@ static void cgroup_rstat_flush_locked(struct cgroup_subsys_state *css)
struct cgroup_subsys_state *pos = cgroup_rstat_updated_list(css, cpu);
for (; pos; pos = pos->rstat_flush_next) {
- struct cgroup_subsys_state *css_iter;
-
bpf_rstat_flush(pos->cgroup, cgroup_parent(pos->cgroup), cpu);
-
- rcu_read_lock();
- list_for_each_entry_rcu(css_iter, &pos->rstat_css_list,
- rstat_css_node)
- css_iter->ss->css_rstat_flush(css_iter, cpu);
- rcu_read_unlock();
+ pos->ss->css_rstat_flush(pos, cpu);
}
/* play nice and yield if necessary */
--
2.47.1
