Re: [PATCH v3 1/3] sched/cpuacct: fix charge percpu cpuusage

From: Tejun Heo
Date: Tue Feb 22 2022 - 13:01:59 EST


On Sun, Feb 20, 2022 at 01:14:24PM +0800, Chengming Zhou wrote:
> The cpuacct_account_field() is always called by the current task
> itself, so it's ok to use __this_cpu_add() to charge the tick time.
>
> But cpuacct_charge() maybe called by update_curr() in load_balance()
> on a random CPU, different from the CPU on which the task is running.
> So __this_cpu_add() will charge that cputime to a random incorrect CPU.
>
> Fixes: 73e6aafd9ea8 ("sched/cpuacct: Simplify the cpuacct code")
> Reported-by: Minye Zhu <zhuminye@xxxxxxxxxxxxx>
> Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>

For all three patches,

Acked-by: Tejun Heo <tj@xxxxxxxxxx>

Thanks.

--
tejun