RE: [PATCH 4/5] selftests/resctrl: Kill the child process before exiting the parent process if an exception occurs

From: tan.shaopeng@xxxxxxxxxxx
Date: Tue Sep 27 2022 - 05:26:35 EST


Hi Reinette,

> On 9/13/2022 6:51 PM, Shaopeng Tan wrote:
>
> ...
>
> > @@ -218,11 +219,11 @@ int cat_perf_miss_val(int cpu_no, int n, char
> *cache_type)
> > }
> > }
> > close(pipefd[0]);
> > - kill(bm_pid, SIGKILL);
> > }
> >
> > - if (bm_pid)
> > - umount_resctrlfs();
> > +out:
> > + kill(bm_pid, SIGKILL);
> > + umount_resctrlfs();
> >
>
> From what I can tell both parent and child will now run this code. So both will
> attempt to unmount resctrl fs and the child will attempt to kill PID 0?

Thanks for your advice. There are problems as you point out.
I think it is complicated if we fix this bug like MBM/MBA/CMT test using sigaction().
It seems this bug cannot be solved easily.
Please give me some time.

Best Regards,
Shaopeng