Merge tag 'cgroup-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - Per-cpu cpu usage stats are now tracked

   This currently isn't printed out in the cgroupfs interface and can
   only be accessed through e.g. BPF. Should decide on a not-too-ugly
   way to show per-cpu stats in cgroupfs

 - cpuset received some cleanups and prepatory patches for the pending
   cpus.exclusive patchset which will allow cpuset partitions to be
   created below non-partition parents, which should ease the management
   of partition cpusets

 - A lot of code and documentation cleanup patches

 - tools/testing/selftests/cgroup/test_cpuset.c added

* tag 'cgroup-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (32 commits)
  cgroup: Avoid -Wstringop-overflow warnings
  cgroup:namespace: Remove unused cgroup_namespaces_init()
  cgroup/rstat: Record the cumulative per-cpu time of cgroup and its descendants
  cgroup: clean up if condition in cgroup_pidlist_start()
  cgroup: fix obsolete function name in cgroup_destroy_locked()
  Documentation: cgroup-v2.rst: Correct number of stats entries
  cgroup: fix obsolete function name above css_free_rwork_fn()
  cgroup/cpuset: fix kernel-doc
  cgroup: clean up printk()
  cgroup: fix obsolete comment above cgroup_create()
  docs: cgroup-v1: fix typo
  docs: cgroup-v1: correct the term of Page Cache organization in inode
  cgroup/misc: Store atomic64_t reads to u64
  cgroup/misc: Change counters to be explicit 64bit types
  cgroup/misc: update struct members descriptions
  cgroup: remove cgrp->kn check in css_populate_dir()
  cgroup: fix obsolete function name
  cgroup: use cached local variable parent in for loop
  cgroup: remove obsolete comment above struct cgroupstats
  cgroup: put cgroup_tryget_css() inside CONFIG_CGROUP_SCHED
  ...

3 files changed, 27 insertions, 17 deletions

diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index ae20dbb885d66e..f1b3151ac30bf0 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -342,6 +342,20 @@ struct cgroup_rstat_cpu {
 	struct cgroup_base_stat last_bstat;
 
 	/*
+	 * This field is used to record the cumulative per-cpu time of
+	 * the cgroup and its descendants. Currently it can be read via
+	 * eBPF/drgn etc, and we are still trying to determine how to
+	 * expose it in the cgroupfs interface.
+	 */
+	struct cgroup_base_stat subtree_bstat;
+
+	/*
+	 * Snapshots at the last reading. These are used to calculate the
+	 * deltas to propagate to the per-cpu subtree_bstat.
+	 */
+	struct cgroup_base_stat last_subtree_bstat;
+
+	/*
 	 * Child cgroups with stat updates on this cpu since the last read
 	 * are linked on the parent's ->updated_children through
 	 * ->updated_next.
diff --git a/include/linux/misc_cgroup.h b/include/linux/misc_cgroup.h
index c238207d161569..e799b1f8d05bb3 100644
--- a/include/linux/misc_cgroup.h
+++ b/include/linux/misc_cgroup.h
@@ -31,17 +31,18 @@ struct misc_cg;
  * struct misc_res: Per cgroup per misc type resource
  * @max: Maximum limit on the resource.
  * @usage: Current usage of the resource.
- * @failed: True if charged failed for the resource in a cgroup.
+ * @events: Number of times, the resource limit exceeded.
  */
 struct misc_res {
-	unsigned long max;
-	atomic_long_t usage;
-	atomic_long_t events;
+	u64 max;
+	atomic64_t usage;
+	atomic64_t events;
 };
 
 /**
  * struct misc_cg - Miscellaneous controller's cgroup structure.
  * @css: cgroup subsys state object.
+ * @events_file: Handle for the misc resources events file.
  * @res: Array of misc resources usage in the cgroup.
  */
 struct misc_cg {
@@ -53,12 +54,10 @@ struct misc_cg {
 	struct misc_res res[MISC_CG_RES_TYPES];
 };
 
-unsigned long misc_cg_res_total_usage(enum misc_res_type type);
-int misc_cg_set_capacity(enum misc_res_type type, unsigned long capacity);
-int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg,
-		       unsigned long amount);
-void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg,
-		      unsigned long amount);
+u64 misc_cg_res_total_usage(enum misc_res_type type);
+int misc_cg_set_capacity(enum misc_res_type type, u64 capacity);
+int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg, u64 amount);
+void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg, u64 amount);
 
 /**
  * css_misc() - Get misc cgroup from the css.
@@ -99,27 +98,26 @@ static inline void put_misc_cg(struct misc_cg *cg)
 
 #else /* !CONFIG_CGROUP_MISC */
 
-static inline unsigned long misc_cg_res_total_usage(enum misc_res_type type)
+static inline u64 misc_cg_res_total_usage(enum misc_res_type type)
 {
 	return 0;
 }
 
-static inline int misc_cg_set_capacity(enum misc_res_type type,
-				       unsigned long capacity)
+static inline int misc_cg_set_capacity(enum misc_res_type type, u64 capacity)
 {
 	return 0;
 }
 
 static inline int misc_cg_try_charge(enum misc_res_type type,
 				     struct misc_cg *cg,
-				     unsigned long amount)
+				     u64 amount)
 {
 	return 0;
 }
 
 static inline void misc_cg_uncharge(enum misc_res_type type,
 				    struct misc_cg *cg,
-				    unsigned long amount)
+				    u64 amount)
 {
 }
 
diff --git a/include/uapi/linux/cgroupstats.h b/include/uapi/linux/cgroupstats.h
index aa306e4cd6c1f8..80b2c85944806d 100644
--- a/include/uapi/linux/cgroupstats.h
+++ b/include/uapi/linux/cgroupstats.h
@@ -24,8 +24,6 @@
  * basis. This data is shared using taskstats.
  *
  * Most of these states are derived by looking at the task->state value
- * For the nr_io_wait state, a flag in the delay accounting structure
- * indicates that the task is waiting on IO
  *
  * Each member is aligned to a 8 byte boundary.
  */