Re: [PATCH 2/3] arm64: Convert cpu_do_idle() to using cpuidle context helpers

From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
To: Marc Zyngier <maz@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org,
	Will Deacon <will@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Valentin Schneider <valentin.schneider@arm.com>,
	Alexandru Elisei <alexandru.elisei@arm.com>,
	Russell King <linux@armlinux.org.uk>,
	kernel-team@android.com
Subject: Re: [PATCH 2/3] arm64: Convert cpu_do_idle() to using cpuidle context helpers
Date: Fri, 11 Jun 2021 17:48:08 +0100	[thread overview]
Message-ID: <20210611164808.GB9252@lpieralisi> (raw)
In-Reply-To: <20210608172715.2396787-3-maz@kernel.org>

On Tue, Jun 08, 2021 at 06:27:14PM +0100, Marc Zyngier wrote:
> Now that we have helpers that are aware of the pseudo-NMI
> feature, introduce them to cpu_do_idle(). This allows for
> some nice cleanup.
> 
> No functional change intended.
> 
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> ---
>  arch/arm64/kernel/process.c | 41 ++++++++-----------------------------
>  1 file changed, 9 insertions(+), 32 deletions(-)

Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

> diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> index b4bb67f17a2c..f99144eda8dc 100644
> --- a/arch/arm64/kernel/process.c
> +++ b/arch/arm64/kernel/process.c
> @@ -46,9 +46,9 @@
>  #include <linux/prctl.h>
>  
>  #include <asm/alternative.h>
> -#include <asm/arch_gicv3.h>
>  #include <asm/compat.h>
>  #include <asm/cpufeature.h>
> +#include <asm/cpuidle.h>
>  #include <asm/cacheflush.h>
>  #include <asm/exec.h>
>  #include <asm/fpsimd.h>
> @@ -74,33 +74,6 @@ EXPORT_SYMBOL_GPL(pm_power_off);
>  
>  void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
>  
> -static void noinstr __cpu_do_idle(void)
> -{
> -	dsb(sy);
> -	wfi();
> -}
> -
> -static void noinstr __cpu_do_idle_irqprio(void)
> -{
> -	unsigned long pmr;
> -	unsigned long daif_bits;
> -
> -	daif_bits = read_sysreg(daif);
> -	write_sysreg(daif_bits | PSR_I_BIT | PSR_F_BIT, daif);
> -
> -	/*
> -	 * Unmask PMR before going idle to make sure interrupts can
> -	 * be raised.
> -	 */
> -	pmr = gic_read_pmr();
> -	gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
> -
> -	__cpu_do_idle();
> -
> -	gic_write_pmr(pmr);
> -	write_sysreg(daif_bits, daif);
> -}
> -
>  /*
>   *	cpu_do_idle()
>   *
> @@ -112,10 +85,14 @@ static void noinstr __cpu_do_idle_irqprio(void)
>   */
>  void noinstr cpu_do_idle(void)
>  {
> -	if (system_uses_irq_prio_masking())
> -		__cpu_do_idle_irqprio();
> -	else
> -		__cpu_do_idle();
> +	struct arm_cpuidle_context context;
> +
> +	arm_cpuidle_save_context(&context);
> +
> +	dsb(sy);
> +	wfi();
> +
> +	arm_cpuidle_restore_context(&context);
>  }
>  
>  /*
> -- 
> 2.30.2
> 

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel