Re: [PATCH] taskstats: fix CGROUPSTATS_CMD_GET for cgroup v2

From: Tejun Heo
Date: Thu Sep 10 2020 - 10:39:47 EST


On Thu, Sep 10, 2020 at 01:52:07PM +0800, Chengming Zhou wrote:
> We found cgroupstats_build would return -EINVAL when using netlink
> CGROUPSTATS_CMD_GET interface to get stats on cgroup v2. Fix it by
> supporting cgroup v2 kernfs directory in cgroupstats_build, and export
> cgroup2_fs_type like we did for cgroup_fs_type.
>
> Reported-by: Daowen Luo <luodaowen.backend@xxxxxxxxxxxxx>
> Tested-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
> Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>

The exclusion of cgroupstats from v2 interface was intentional due to the
duplication and inconsistencies with other statistics. If you need these
numbers, please justify and add them to the appropriate cgroupfs stat file.

Thanks.

--
tejun