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| author | Tejun Heo <tj@kernel.org> | 2016-03-03 09:57:57 -0500 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2016-03-03 09:57:57 -0500 |
| commit | 2378d8b8ba3d2adffb4f98c0c60ee2f448b3be69 (patch) | |
| tree | f3278fe0e6d933d2a89f94575c747bbbdb5fd404 | |
| parent | fa06235b8eb0ae87a962e023243dba1eb4e7160d (diff) | |
| download | linux-2378d8b8ba3d2adffb4f98c0c60ee2f448b3be69.tar.bz2 | |
cgroup: re-hash init_css_set after subsystems are initialized
css_sets are hashed by their subsys[] contents and in cgroup_init()
init_css_set is hashed early, before subsystem inits, when all entries
in its subsys[] are NULL, so that cgroup_dfl_root initialization can
find and link to it. As subsystems are initialized,
init_css_set.subsys[] is filled up but the hashing is never updated
making init_css_set hashed in the wrong place. While incorrect, this
doesn't cause a critical failure as css_set management code would
create an identical css_set dynamically.
Fix it by rehashing init_css_set after subsystems are initialized.
While at it, drop unnecessary @key local variable.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Zefan Li <lizefan@huawei.com>
| -rw-r--r-- | kernel/cgroup.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 46529502e9d5..e97772b42dfb 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -5266,7 +5266,6 @@ static u16 cgroup_disable_mask __initdata; int __init cgroup_init(void) { struct cgroup_subsys *ss; - unsigned long key; int ssid; BUILD_BUG_ON(CGROUP_SUBSYS_COUNT > 16); @@ -5276,9 +5275,12 @@ int __init cgroup_init(void) mutex_lock(&cgroup_mutex); - /* Add init_css_set to the hash table */ - key = css_set_hash(init_css_set.subsys); - hash_add(css_set_table, &init_css_set.hlist, key); + /* + * Add init_css_set to the hash table so that dfl_root can link to + * it during init. + */ + hash_add(css_set_table, &init_css_set.hlist, + css_set_hash(init_css_set.subsys)); BUG_ON(cgroup_setup_root(&cgrp_dfl_root, 0)); @@ -5331,6 +5333,11 @@ int __init cgroup_init(void) ss->bind(init_css_set.subsys[ssid]); } + /* init_css_set.subsys[] has been updated, re-hash */ + hash_del(&init_css_set.hlist); + hash_add(css_set_table, &init_css_set.hlist, + css_set_hash(init_css_set.subsys)); + WARN_ON(sysfs_create_mount_point(fs_kobj, "cgroup")); WARN_ON(register_filesystem(&cgroup_fs_type)); WARN_ON(register_filesystem(&cgroup2_fs_type)); |