Re: [-next v2 4/4] cpuset: add helpers for cpus read and cpuset_mutex locks

[Waiman Long <llong@redhat.com>]

On 8/13/25 4:29 AM, Chen Ridong wrote:
> From: Chen Ridong <chenridong@huawei.com>
>
> cpuset: add helpers for cpus_read_lock and cpuset_mutex
>
> Replace repetitive locking patterns with new helpers:
> - cpus_read_cpuset_lock()
> - cpus_read_cpuset_unlock()
>
> This makes the code cleaner and ensures consistent lock ordering.
>
> Signed-off-by: Chen Ridong <chenridong@huawei.com>
> ---
>   kernel/cgroup/cpuset-internal.h |  2 ++
>   kernel/cgroup/cpuset-v1.c       | 12 +++------
>   kernel/cgroup/cpuset.c          | 48 +++++++++++++++------------------
>   3 files changed, 28 insertions(+), 34 deletions(-)
>
> diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
> index 75b3aef39231..6fb00c96044d 100644
> --- a/kernel/cgroup/cpuset-internal.h
> +++ b/kernel/cgroup/cpuset-internal.h
> @@ -276,6 +276,8 @@ int cpuset_update_flag(cpuset_flagbits_t bit, struct cpuset *cs, int turning_on)
>   ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
>   				    char *buf, size_t nbytes, loff_t off);
>   int cpuset_common_seq_show(struct seq_file *sf, void *v);
> +void cpus_read_cpuset_lock(void);
> +void cpus_read_cpuset_unlock(void);

The names are not intuitive. I would prefer just extend the 
cpuset_lock/unlock to include cpus_read_lock/unlock and we use 
cpuset_lock/unlock consistently in the cpuset code. Also, there is now 
no external user of cpuset_lock/unlock, we may as well remove them from 
include/linux/cpuset.h.

Cheers,
Longman