Re: [PATCH v2] MIPS: SMP-CPS: fix build error when HOTPLUG_CPU not set

From: Thomas Bogendoerfer
Date: Sun Feb 19 2023 - 04:03:07 EST


On Fri, Feb 17, 2023 at 12:07:49PM -0800, Randy Dunlap wrote:
> When MIPS_CPS=y, MIPS_CPS_PM is not set, HOTPLUG_CPU is not set, and
> KEXEC=y, cps_shutdown_this_cpu() attempts to call cps_pm_enter_state(),
> which is not built when MIPS_CPS_PM is not set.
> Conditionally execute the else branch based on CONFIG_HOTPLUG_CPU
> to remove the build error.
> This build failure is from a randconfig file.
>
> mips-linux-ld: arch/mips/kernel/smp-cps.o: in function `$L162':
> smp-cps.c:(.text.cps_kexec_nonboot_cpu+0x31c): undefined reference to `cps_pm_enter_state'
>
> Fixes: 1447864bee4c ("MIPS: kexec: CPS systems to halt nonboot CPUs")
> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Cc: Dengcheng Zhu <dzhu@xxxxxxxxxxxx>
> Cc: Paul Burton <paulburton@xxxxxxxxxx>
> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> Cc: linux-mips@xxxxxxxxxxxxxxx
> Cc: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxx>
> ---
> v2: use IS_ENABLED() instead of #ifdef-ery (Sergei)
>
> arch/mips/kernel/smp-cps.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff -- a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c
> --- a/arch/mips/kernel/smp-cps.c
> +++ b/arch/mips/kernel/smp-cps.c
> @@ -424,9 +424,11 @@ static void cps_shutdown_this_cpu(enum c
> wmb();
> }
> } else {
> - pr_debug("Gating power to core %d\n", core);
> - /* Power down the core */
> - cps_pm_enter_state(CPS_PM_POWER_GATED);
> + if (IS_ENABLED(CONFIG_HOTPLUG_CPU)) {
> + pr_debug("Gating power to core %d\n", core);
> + /* Power down the core */
> + cps_pm_enter_state(CPS_PM_POWER_GATED);
> + }
> }
> }
>

applied to mips-next.

Thomas.

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