Merge tag 'cgroup-for-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - cpuset now supports remote partitions where CPUs can be reserved for
   exclusive use down the tree without requiring all the intermediate
   nodes to be partitions. This makes it easier to use partitions
   without modifying existing cgroup hierarchy.

 - cpuset partition configuration behavior improvement

 - cgroup_favordynmods= boot param added to allow setting the flag on
   boot on cgroup1

 - Misc code and doc updates

* tag 'cgroup-for-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  docs/cgroup: Add the list of threaded controllers to cgroup-v2.rst
  cgroup: use legacy_name for cgroup v1 disable info
  cgroup/cpuset: Cleanup signedness issue in cpu_exclusive_check()
  cgroup/cpuset: Enable invalid to valid local partition transition
  cgroup: add cgroup_favordynmods= command-line option
  cgroup/cpuset: Extend test_cpuset_prs.sh to test remote partition
  cgroup/cpuset: Documentation update for partition
  cgroup/cpuset: Check partition conflict with housekeeping setup
  cgroup/cpuset: Introduce remote partition
  cgroup/cpuset: Add cpuset.cpus.exclusive for v2
  cgroup/cpuset: Add cpuset.cpus.exclusive.effective for v2
  cgroup/cpuset: Fix load balance state in update_partition_sd_lb()
  cgroup: Avoid extra dereference in css_populate_dir()
  cgroup: Check for ret during cgroup1_base_files cft addition

1 files changed, 21 insertions, 9 deletions

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 1fb7f562289d..c09531bace38 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -207,6 +207,8 @@ static u16 have_exit_callback __read_mostly;
 static u16 have_release_callback __read_mostly;
 static u16 have_canfork_callback __read_mostly;
 
+static bool have_favordynmods __ro_after_init = IS_ENABLED(CONFIG_CGROUP_FAVOR_DYNMODS);
+
 /* cgroup namespace for init task */
 struct cgroup_namespace init_cgroup_ns = {
 	.ns.count	= REFCOUNT_INIT(2),
@@ -1350,7 +1352,9 @@ static void cgroup_destroy_root(struct cgroup_root *root)
 		cgroup_root_count--;
 	}
 
-	cgroup_favor_dynmods(root, false);
+	if (!have_favordynmods)
+		cgroup_favor_dynmods(root, false);
+
 	cgroup_exit_root_id(root);
 
 	cgroup_unlock();
@@ -1719,20 +1723,22 @@ static int css_populate_dir(struct cgroup_subsys_state *css)
 
 	if (!css->ss) {
 		if (cgroup_on_dfl(cgrp)) {
-			ret = cgroup_addrm_files(&cgrp->self, cgrp,
+			ret = cgroup_addrm_files(css, cgrp,
 						 cgroup_base_files, true);
 			if (ret < 0)
 				return ret;
 
 			if (cgroup_psi_enabled()) {
-				ret = cgroup_addrm_files(&cgrp->self, cgrp,
+				ret = cgroup_addrm_files(css, cgrp,
 							 cgroup_psi_files, true);
 				if (ret < 0)
 					return ret;
 			}
 		} else {
-			cgroup_addrm_files(css, cgrp,
-					   cgroup1_base_files, true);
+			ret = cgroup_addrm_files(css, cgrp,
+						 cgroup1_base_files, true);
+			if (ret < 0)
+				return ret;
 		}
 	} else {
 		list_for_each_entry(cfts, &css->ss->cfts, node) {
@@ -2243,9 +2249,9 @@ static int cgroup_init_fs_context(struct fs_context *fc)
 	fc->user_ns = get_user_ns(ctx->ns->user_ns);
 	fc->global = true;
 
-#ifdef CONFIG_CGROUP_FAVOR_DYNMODS
-	ctx->flags |= CGRP_ROOT_FAVOR_DYNMODS;
-#endif
+	if (have_favordynmods)
+		ctx->flags |= CGRP_ROOT_FAVOR_DYNMODS;
+
 	return 0;
 }
 
@@ -6121,7 +6127,7 @@ int __init cgroup_init(void)
 
 		if (cgroup1_ssid_disabled(ssid))
 			pr_info("Disabling %s control group subsystem in v1 mounts\n",
-				ss->name);
+				ss->legacy_name);
 
 		cgrp_dfl_root.subsys_mask |= 1 << ss->id;
 
@@ -6764,6 +6770,12 @@ static int __init enable_cgroup_debug(char *str)
 }
 __setup("cgroup_debug", enable_cgroup_debug);
 
+static int __init cgroup_favordynmods_setup(char *str)
+{
+	return (kstrtobool(str, &have_favordynmods) == 0);
+}
+__setup("cgroup_favordynmods=", cgroup_favordynmods_setup);
+
 /**
  * css_tryget_online_from_dir - get corresponding css from a cgroup dentry
  * @dentry: directory dentry of interest