From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [PATCH v3 05/10] VFIO: platform: add vfio_platform_is_active Date: Wed, 2 Sep 2015 21:29:32 +0200 Message-ID: <20150902192932.GT10991@cbox> References: <1439212864-12954-1-git-send-email-eric.auger@linaro.org> <1439212864-12954-6-git-send-email-eric.auger@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: eric.auger@st.com, kvm@vger.kernel.org, patches@linaro.org, marc.zyngier@arm.com, linux-kernel@vger.kernel.org, alex.williamson@redhat.com, pbonzini@redhat.com, feng.wu@intel.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org To: Eric Auger Return-path: Content-Disposition: inline In-Reply-To: <1439212864-12954-6-git-send-email-eric.auger@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org On Mon, Aug 10, 2015 at 03:20:59PM +0200, Eric Auger wrote: > This function returns whether the IRQ is active at irqchip level or > VFIO masked. If either is true, it is considered the IRQ is active. > Currently there is no way to differentiate userspace masked IRQ from > automasked IRQ. There might be false detection of activity. However > it is currently acceptable to have false detection. > > Signed-off-by: Eric Auger > > --- > --- > drivers/vfio/platform/vfio_platform_irq.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c > index a285384..efaee58 100644 > --- a/drivers/vfio/platform/vfio_platform_irq.c > +++ b/drivers/vfio/platform/vfio_platform_irq.c > @@ -205,6 +205,23 @@ static int vfio_platform_set_automasked(struct vfio_platform_irq *irq, > return 0; > } > > +static int vfio_platform_is_active(struct vfio_platform_irq *irq) > +{ > + unsigned long flags; > + bool active, masked, outstanding; > + int ret; > + > + spin_lock_irqsave(&irq->lock, flags); > + > + ret = irq_get_irqchip_state(irq->hwirq, IRQCHIP_STATE_ACTIVE, &active); > + BUG_ON(ret); > + masked = irq->masked; > + outstanding = active || masked; outstanding? why not just return active || masked ? -Christoffer > + > + spin_unlock_irqrestore(&irq->lock, flags); > + return outstanding; > +} > + > static void vfio_platform_irq_bypass_stop(struct irq_bypass_producer *prod) > { > } > -- > 1.9.1 >