Re: [PATCH] arm64/smp: Remove unused irq variable in arch_show_interrupts()

From: Geert Uytterhoeven
Date: Tue Jan 26 2021 - 06:34:36 EST


Hi Zenghui,

On Fri, Dec 25, 2020 at 8:05 AM Zenghui Yu <yuzenghui@xxxxxxxxxx> wrote:
> On 2020/12/15 18:30, Geert Uytterhoeven wrote:
> > arch/arm64/kernel/smp.c: In function ‘arch_show_interrupts’:
> > arch/arm64/kernel/smp.c:808:16: warning: unused variable ‘irq’ [-Wunused-variable]
> > 808 | unsigned int irq = irq_desc_get_irq(ipi_desc[i]);
> > | ^~~
> >
> > The removal of the last user forgot to remove the variable.
> >
> > Fixes: 2f516e34383d0e97 ("arm64/smp: Use irq_desc_kstat_cpu() in arch_show_interrupts()")
>
> This is in mainline now and the commit id is 5089bc51f81f.
>
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > ---
> > One more issue in irq-core-2020-12-14.
> >
> > arch/arm64/kernel/smp.c | 1 -
> > 1 file changed, 1 deletion(-)
> >
> > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
> > index 3aef3bc22d3250b5..10b39328268687e3 100644
> > --- a/arch/arm64/kernel/smp.c
> > +++ b/arch/arm64/kernel/smp.c
> > @@ -805,7 +805,6 @@ int arch_show_interrupts(struct seq_file *p, int prec)
> > unsigned int cpu, i;
> >
> > for (i = 0; i < NR_IPI; i++) {
> > - unsigned int irq = irq_desc_get_irq(ipi_desc[i]);
> > seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
> > prec >= 4 ? " " : "");
> > for_each_online_cpu(cpu)
>
> And I guess we have the same problem on 32-bit ARM. 'irq' in
> show_ipi_list() is no longer used since commit 88c637748e31
> ("ARM: smp: Use irq_desc_kstat_cpu() in show_ipi_list()").

Indeed. I didn't see it with my compiler version, but Wolfram did, and
sent a patch:
https://lore.kernel.org/linux-arm-kernel/20201228120147.59387-1-wsa+renesas@xxxxxxxxxxxxxxxxxxxx/

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds