Re: [PATCH v2 6/8] RISC-V: Add required checks during clock source init

[Atish Patra]

On 1/8/19 3:57 AM, Anup Patel wrote:
> Few nit changes..
>
> Prefer, "clocksource/drivers/riscv:" prefix instead of "RISC-V:" for
> this patch.
>
> On Tue, Jan 8, 2019 at 3:08 PM Atish Patra <atish.patra@xxxxxxx> wrote:
> > Currently, clocksource registration happens for an invalid cpu
> > for non-smp kernels. This lead to kernel panic as cpu hotplug
> > registration will fail for those cpus. Moreover,
> > riscv_hartid_to_cpuid can return errors now.
> >
> > Do not proceed if hartid or cpuid is invalid. Take this opprtunity
> > to print appropriate error strings for different failure cases.
> >
> > Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
> > ---
> >   drivers/clocksource/timer-riscv.c | 23 ++++++++++++++++++++---
> >   1 file changed, 20 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
> > index 43189220..d9b914e9 100644
> > --- a/drivers/clocksource/timer-riscv.c
> > +++ b/drivers/clocksource/timer-riscv.c
> > @@ -95,14 +95,31 @@ static int __init riscv_timer_init_dt(struct device_node *n)
> >          struct clocksource *cs;
> >
> >          hartid = riscv_of_processor_hartid(n);
> > +       if (hartid < 0) {
> > +               pr_warn("Not valid hartid for node [%pOF] error = [%d]\n",
> > +                       n, hartid);
> > +               return hartid;
> > +       }
>
> Add empty line here.
>
> >          cpuid = riscv_hartid_to_cpuid(hartid);
>
> Remove empty line here
>
> > +       if (cpuid < 0) {
> > +               pr_warn("Invalid cpuid for hartid [%d]\n", hartid);
> > +               return cpuid;
> > +       }
> > +
> >          if (cpuid != smp_processor_id())
> >                  return 0;
> >
> > +       pr_err("%s: Registering clocksource cpuid [%d] hartid [%d]\n",
> > +              __func__, cpuid, hartid);
> >          cs = per_cpu_ptr(&riscv_clocksource, cpuid);
> > -       clocksource_register_hz(cs, riscv_timebase);
> > +       error = clocksource_register_hz(cs, riscv_timebase);
>
> Remove empty line here.
>
> > +       if (error) {
> > +               pr_err("RISCV timer register failed [%d] for cpu = [%d]\n",
> > +                      error, cpuid);
> > +               return error;
> > +       }
>
> Add empty line here.
>
> >          sched_clock_register(riscv_sched_clock,
> >                          BITS_PER_LONG, riscv_timebase);
> >
> > @@ -110,8 +127,8 @@ static int __init riscv_timer_init_dt(struct device_node *n)
> >                           "clockevents/riscv/timer:starting",
> >                           riscv_timer_starting_cpu, riscv_timer_dying_cpu);
> >          if (error)
> > -               pr_err("RISCV timer register failed [%d] for cpu = [%d]\n",
> > -                      error, cpuid);
> > +               pr_err("cpu hp setup state failed for RISCV timer [%d]\n",
> > +                      error);
> >          return error;
> >   }
> >
> > --
> > 2.7.4
>
> Apart from above, looks good to me.
>
> Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>

Thanks for the review. I will fix the empty line issues and subject line.


> Regards,
> Anup