Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752093AbaJYSdr (ORCPT ); Sat, 25 Oct 2014 14:33:47 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:41568 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751725AbaJYSdn (ORCPT ); Sat, 25 Oct 2014 14:33:43 -0400 From: "john.liuli" To: CC: , , , , , , , , , Li Liu Subject: [RFC PATCH 2/2] Assign a new irq handler while irqfd enabled Date: Sat, 25 Oct 2014 16:24:54 +0800 Message-ID: <1414225494-2208-3-git-send-email-john.liuli@huawei.com> X-Mailer: git-send-email 1.9.0.msysgit.0 In-Reply-To: <1414225494-2208-1-git-send-email-john.liuli@huawei.com> References: <1414225494-2208-1-git-send-email-john.liuli@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.142.143.9] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020209.544B5EAA.0135,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: bba50b150d6316fe59f4e618c40f3452 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Li Liu This irq handler will get the interrupt reason from a shared memory. And will be assigned only while irqfd enabled. Signed-off-by: Li Liu --- drivers/virtio/virtio_mmio.c | 34 ++++++++++++++++++++++++++++++++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 28ddb55..7229605 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -259,7 +259,31 @@ static irqreturn_t vm_interrupt(int irq, void *opaque) return ret; } +/* Notify all virtqueues on an interrupt. */ +static irqreturn_t vm_interrupt_irqfd(int irq, void *opaque) +{ + struct virtio_mmio_device *vm_dev = opaque; + struct virtio_mmio_vq_info *info; + unsigned long status; + unsigned long flags; + irqreturn_t ret = IRQ_NONE; + /* Read the interrupt reason and reset it */ + status = *vm_dev->isr_mem; + *vm_dev->isr_mem = 0x0; + + if (unlikely(status & VIRTIO_MMIO_INT_CONFIG)) { + virtio_config_changed(&vm_dev->vdev); + ret = IRQ_HANDLED; + } + + spin_lock_irqsave(&vm_dev->lock, flags); + list_for_each_entry(info, &vm_dev->virtqueues, node) + ret |= vring_interrupt(irq, info->vq); + spin_unlock_irqrestore(&vm_dev->lock, flags); + + return ret; +} static void vm_del_vq(struct virtqueue *vq) { @@ -391,6 +415,7 @@ error_available: return ERR_PTR(err); } +#define VIRTIO_MMIO_F_IRQFD (1 << 7) static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs, struct virtqueue *vqs[], vq_callback_t *callbacks[], @@ -400,8 +425,13 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs, unsigned int irq = platform_get_irq(vm_dev->pdev, 0); int i, err; - err = request_irq(irq, vm_interrupt, IRQF_SHARED, - dev_name(&vdev->dev), vm_dev); + if (*vm_dev->isr_mem & VIRTIO_MMIO_F_IRQFD) { + err = request_irq(irq, vm_interrupt_irqfd, IRQF_SHARED, + dev_name(&vdev->dev), vm_dev); + } else { + err = request_irq(irq, vm_interrupt, IRQF_SHARED, + dev_name(&vdev->dev), vm_dev); + } if (err) return err; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/