diff options
| author | Shakeel Butt <shakeel.butt@linux.dev> | 2025-06-17 12:57:22 -0700 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2025-06-17 09:58:45 -1000 |
| commit | 1257b8786ac689a2ce5fe3e1741c65038035adc6 (patch) | |
| tree | 4765bf5a78d295f2aca3dce1d901ec7280110b71 /include/linux | |
| parent | 5da4f9db980cc475bb6f027153cce75eaa3026ec (diff) | |
cgroup: support to enable nmi-safe css_rstat_updated
Add necessary infrastructure to enable the nmi-safe execution of
css_rstat_updated(). Currently css_rstat_updated() takes a per-cpu
per-css raw spinlock to add the given css in the per-cpu per-css update
tree. However the kernel can not spin in nmi context, so we need to
remove the spinning on the raw spinlock in css_rstat_updated().
To support lockless css_rstat_updated(), let's add necessary data
structures in the css and ss structures.
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Tested-by: JP Kobryn <inwardvessel@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/cgroup-defs.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index cd7f093e34cd..04191d99228c 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -384,6 +384,9 @@ struct css_rstat_cpu { */ struct cgroup_subsys_state *updated_children; struct cgroup_subsys_state *updated_next; /* NULL if not on the list */ + + struct llist_node lnode; /* lockless list for update */ + struct cgroup_subsys_state *owner; /* back pointer */ }; /* @@ -822,6 +825,7 @@ struct cgroup_subsys { spinlock_t rstat_ss_lock; raw_spinlock_t __percpu *rstat_ss_cpu_lock; + struct llist_head __percpu *lhead; /* lockless update list head */ }; extern struct percpu_rw_semaphore cgroup_threadgroup_rwsem; |