From: Chuyi Zhou Date: Thu, 4 Sep 2025 07:45:05 +0000 (+0800) Subject: cgroup: Remove unused cgroup_subsys::post_attach X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d8b269e009bbc471cb2735b5f737839495efce3b;p=thirdparty%2Fkernel%2Fstable.git cgroup: Remove unused cgroup_subsys::post_attach cgroup_subsys::post_attach callback was introduced in commit 5cf1cacb49ae ("cgroup, cpuset: replace cpuset_post_attach_flush() with cgroup_subsys->post_attach callback") and only cpuset would use this callback to wait for the mm migration to complete at the end of __cgroup_procs_write(). Since the previous patch defer the flush operation until returning to userspace, no one use this callback now. Remove this callback from cgroup_subsys. Signed-off-by: Chuyi Zhou Acked-by: Waiman Long Signed-off-by: Tejun Heo --- diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index 539c64eeef38f..92ed6d18266d1 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -763,7 +763,6 @@ struct cgroup_subsys { int (*can_attach)(struct cgroup_taskset *tset); void (*cancel_attach)(struct cgroup_taskset *tset); void (*attach)(struct cgroup_taskset *tset); - void (*post_attach)(void); int (*can_fork)(struct task_struct *task, struct css_set *cset); void (*cancel_fork)(struct task_struct *task, struct css_set *cset); diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index b38d7a847ed4a..0dc6ad71f175b 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -3033,10 +3033,6 @@ void cgroup_procs_write_finish(struct task_struct *task, bool threadgroup_locked put_task_struct(task); cgroup_attach_unlock(threadgroup_locked); - - for_each_subsys(ss, ssid) - if (ss->post_attach) - ss->post_attach(); } static void cgroup_print_ss_mask(struct seq_file *seq, u16 ss_mask)