[PATCH 2/4] cgroup: reorder cgroup_subsys fields to save 8 byte
STALE1825d
From: Wei Yang <hidden>
Date: 2021-10-04 08:49:40
Also in:
lkml
Subsystem:
control group (cgroup), the rest · Maintainers:
Tejun Heo, Johannes Weiner, Michal Koutný, Linus Torvalds
On 64bit platform, struct is aligned by 8 bytes by default. By moving cgroup_subsys.depends_on, we fit these adjacent fields into 8 bytes alignment. Signed-off-by: Wei Yang <redacted> --- include/linux/cgroup-defs.h | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index f6d80896daab..4649d09396fd 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h@@ -672,6 +672,15 @@ struct cgroup_subsys { */ bool threaded:1; + /* + * A subsystem may depend on other subsystems. When such subsystem + * is enabled on a cgroup, the depended-upon subsystems are enabled + * together if available. Subsystems enabled due to dependency are + * not visible to userland until explicitly enabled. The following + * specifies the mask of subsystems that this one depends on. + */ + u16 depends_on; + /* the following two fields are initialized automatically during boot */ int id; const char *name;
@@ -698,14 +707,6 @@ struct cgroup_subsys { struct cftype *dfl_cftypes; /* for the default hierarchy */ struct cftype *legacy_cftypes; /* for the legacy hierarchies */ - /* - * A subsystem may depend on other subsystems. When such subsystem - * is enabled on a cgroup, the depended-upon subsystems are enabled - * together if available. Subsystems enabled due to dependency are - * not visible to userland until explicitly enabled. The following - * specifies the mask of subsystems that this one depends on. - */ - u16 depends_on; }; extern struct percpu_rw_semaphore cgroup_threadgroup_rwsem;
--
2.23.0