Re: [PATCH] Iommu: ipmmu-vmsa: replace spin_lock_irqsave with spin_lock in ISR

From: Geert Uytterhoeven
Date: Tue Sep 11 2018 - 11:11:50 EST


CC linux-renesas-soc

On Tue, Sep 11, 2018 at 5:01 PM jun qian <hangdianqj@xxxxxxx> wrote:
>
> As you are already in ISR, it is unnecessary to call spin_lock_irqsave.
>
> Signed-off-by: jun qian <hangdianqj@xxxxxxx>
> ---
> drivers/iommu/ipmmu-vmsa.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index 22b94f8a9a04..afa23d53502c 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -569,9 +569,8 @@ static irqreturn_t ipmmu_irq(int irq, void *dev)
> struct ipmmu_vmsa_device *mmu = dev;
> irqreturn_t status = IRQ_NONE;
> unsigned int i;
> - unsigned long flags;
>
> - spin_lock_irqsave(&mmu->lock, flags);
> + spin_lock(&mmu->lock);
>
> /*
> * Check interrupts for all active contexts.
> @@ -583,7 +582,7 @@ static irqreturn_t ipmmu_irq(int irq, void *dev)
> status = IRQ_HANDLED;
> }
>
> - spin_unlock_irqrestore(&mmu->lock, flags);
> + spin_unlock(&mmu->lock);
>
> return status;
> }
> --
> 2.17.1