Merge tag 'cgroup-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - Attach path bug fixes: migrations spanning multiple source or
   destination cpusets were mishandled, most visibly leaving thread
   affinities stale when the controller is disabled in a threaded
   subtree. Configuration writes could also race an in-flight attach and
   apply stale state, and the deadline task count could get corrupted by
   concurrent updates, skewing SCHED_DEADLINE admission decisions.

 - Memory binding bug fixes: which node masks get applied differed
   between the binding update paths, and tasks cloned with
   CLONE_INTO_CGROUP skipped rebinding entirely. Rebinding also now runs
   once per process instead of repeating for every thread sharing the
   mm.

 - Overhead removals with no behavior change: CPU hotplug iterated tasks
   of cpusets that just inherit the parent's effective masks, and the
   slab-spreading task flag was still being maintained although the SLAB
   allocator that consumed it is long gone.

 - Data-race annotations for benign races so that KCSAN reports stay
   meaningful, selftest coverage for the fixes above along with
   flakiness and portability fixes, and documentation corrections.

* tag 'cgroup-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (34 commits)
  selftests/cgroup: Remove redundant chown in test_cgcore_lesser_ns_open
  selftests/cgroup: Preserve CPU hotplug write errors
  cgroup/cpuset: Add test for partition root invalidation returning wrong CPUs
  cgroup/cpuset: Remove obsolete PFA_SPREAD_SLAB task flag
  docs: cgroup-v2: fix stale "io" controller introduction
  selftests/cgroup: Avoid awk -e in cpuset tests
  cgroup/cpuset: Use WRITE_ONCE() for shared prs_err updates
  selftests/cgroup: add user_usec sanity check in test_cpucg_nice
  cgroup: drop unneeded semicolon
  docs: cgroup-v2: mark memory.pressure and io.pressure as read-write
  selftests/cgroup: Fix minor defects in test_cpuset
  Docs/admin-guide/cgroup-v2: fix delay_nsec unit in io.latency doc
  selftests/cgroup: Remove redundant cg_enter_current() call in test_core
  selftests/cgroup: Add test for cpuset affinity on controller disable
  cgroup/cpuset: Handle the special case of non-moving tasks in cpuset_can_attach()
  cgroup/cpuset: Support multiple destination cpusets for cpuset_*attach()
  selftests/cgroup: fix missing TAP output in test_hugetlb_memcg
  cgroup/cpuset: Support multiple source cpusets for cpuset_*attach()
  cgroup/cpuset: Move mpol_rebind_mm/cpuset_migrate_mm() calls inside cpuset_attach_task()
  cgroup/cpuset: Make attach_ctx.old_cs track task group leader
  ...

3 files changed, 2 insertions, 7 deletions

diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index de2cd6238c2a..7a631a257613 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -896,7 +896,7 @@ static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk)
  * cgroup_threadgroup_change_end - threadgroup exclusion for cgroups
  * @tsk: target task
  *
- * Counterpart of cgroup_threadcgroup_change_begin().
+ * Counterpart of cgroup_threadgroup_change_begin().
  */
 static inline void cgroup_threadgroup_change_end(struct task_struct *tsk)
 {
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index f2aa46a4f871..b905208942bf 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -480,7 +480,7 @@ static inline void cgroup_unlock(void)
 		rcu_read_lock_sched_held() ||				\
 		lockdep_is_held(&cgroup_mutex) ||			\
 		lockdep_is_held(&css_set_lock) ||			\
-		((task)->flags & PF_EXITING) || (__c))
+		(data_race((task)->flags) & PF_EXITING) || (__c))
 #else
 #define task_css_set_check(task, __c)					\
 	rcu_dereference((task)->cgroups)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 193a4a4dcc27..3f100d69b053 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1860,7 +1860,6 @@ static __always_inline bool is_user_task(struct task_struct *task)
 /* Per-process atomic flags. */
 #define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
 #define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
-#define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
 #define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
 #define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
 #define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
@@ -1886,10 +1885,6 @@ TASK_PFA_TEST(SPREAD_PAGE, spread_page)
 TASK_PFA_SET(SPREAD_PAGE, spread_page)
 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
 
-TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
-TASK_PFA_SET(SPREAD_SLAB, spread_slab)
-TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
-
 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)