Re: [PATCH] kallsyms: Fix sleeping function called from invalid context when CONFIG_KALLSYMS_SELFTEST=y

[Leizhen (ThunderTown)]

On 2022/12/21 20:37, Leizhen (ThunderTown) wrote:
>>>> I am not familiar with it. But task_cputime() in
>>>> kernel/sched/cputime.c looks promising. And there must be
>>>> the interface how the user space get this information.
>>>> Some is available via /proc/<PID>/... I am not sure
>>>> if there is a syscall.
>> Please, try to investigate the above hints.
> Yes, I will. Thanks.

Function task_cputime() works well when CONFIG_VIRT_CPU_ACCOUNTING_GEN=y,
but not when CONFIG_TICK_CPU_ACCOUNTING=y. The latter seems to be based on
tick interrupt sampling, rather than recording timestamps during task switches.

> 

-- 
Regards,
  Zhen Lei