Hi Peter/Ingo,
On Wed, 2016-04-06 at 21:59 +1000, Anton Blanchard wrote:
> Hi Peter,
>
> > Ah, so sometihng like:
> >
> > struct pt_regs *regs = task_pt_regs();
> > int index = CPUACCT_USAGE_SYSTEM;
> >
> > if (regs && user_mode(regs))
> > index = CPUACCT_USAGE_USER;
> >
> > should work, right?
>
> Looks good, and the patch below does fix the oops for me.
Can we get this merged please? It's blocking all my boot tests.
If anyone's bothered:
Fixes: d740037fac70 ("sched/cpuacct: Split usage accounting into user_usage and
sys_usage")
cheers
> task_pt_regs() can return NULL for kernel threads, so add a check.
> This fixes an oops at boot on ppc64.
>
> Signed-off-by: Anton Blanchard <an...@samba.org>
> ---
>
> diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
> index df947e0..41f85c4 100644
> --- a/kernel/sched/cpuacct.c
> +++ b/kernel/sched/cpuacct.c
> @@ -316,12 +316,11 @@ static struct cftype files[] = {
> void cpuacct_charge(struct task_struct *tsk, u64 cputime)
> {
> struct cpuacct *ca;
> - int index;
> + int index = CPUACCT_USAGE_SYSTEM;
> + struct pt_regs *regs = task_pt_regs(tsk);
>
> - if (user_mode(task_pt_regs(tsk)))
> + if (regs && user_mode(regs))
> index = CPUACCT_USAGE_USER;
> - else
> - index = CPUACCT_USAGE_SYSTEM;
>
> rcu_read_lock();
>
>
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
