2020-05-12 08:06:40

by Zhu, Lingshan

[permalink] [raw]
Subject: [PATCH V2] ifcvf: move IRQ request/free to status change handlers

This commit move IRQ request and free operations from probe()
to VIRTIO status change handler to comply with VIRTIO spec.

VIRTIO spec 1.1, section 2.1.2 Device Requirements: Device Status Field
The device MUST NOT consume buffers or send any used buffer
notifications to the driver before DRIVER_OK.

Signed-off-by: Zhu Lingshan <[email protected]>
---
changes from V1:
remove ifcvf_stop_datapath() in status == 0 handler, we don't need to do this
twice; handle status == 0 after DRIVER_OK -> !DRIVER_OK handler (Jason Wang)

drivers/vdpa/ifcvf/ifcvf_main.c | 120 ++++++++++++++++++++++++----------------
1 file changed, 73 insertions(+), 47 deletions(-)

diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index abf6a061..d529ed6 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -28,6 +28,60 @@ static irqreturn_t ifcvf_intr_handler(int irq, void *arg)
return IRQ_HANDLED;
}

+static void ifcvf_free_irq_vectors(void *data)
+{
+ pci_free_irq_vectors(data);
+}
+
+static void ifcvf_free_irq(struct ifcvf_adapter *adapter, int queues)
+{
+ struct pci_dev *pdev = adapter->pdev;
+ struct ifcvf_hw *vf = &adapter->vf;
+ int i;
+
+
+ for (i = 0; i < queues; i++)
+ devm_free_irq(&pdev->dev, vf->vring[i].irq, &vf->vring[i]);
+
+ ifcvf_free_irq_vectors(pdev);
+}
+
+static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
+{
+ struct pci_dev *pdev = adapter->pdev;
+ struct ifcvf_hw *vf = &adapter->vf;
+ int vector, i, ret, irq;
+
+ ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
+ IFCVF_MAX_INTR, PCI_IRQ_MSIX);
+ if (ret < 0) {
+ IFCVF_ERR(pdev, "Failed to alloc IRQ vectors\n");
+ return ret;
+ }
+
+ for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+ snprintf(vf->vring[i].msix_name, 256, "ifcvf[%s]-%d\n",
+ pci_name(pdev), i);
+ vector = i + IFCVF_MSI_QUEUE_OFF;
+ irq = pci_irq_vector(pdev, vector);
+ ret = devm_request_irq(&pdev->dev, irq,
+ ifcvf_intr_handler, 0,
+ vf->vring[i].msix_name,
+ &vf->vring[i]);
+ if (ret) {
+ IFCVF_ERR(pdev,
+ "Failed to request irq for vq %d\n", i);
+ ifcvf_free_irq(adapter, i);
+
+ return ret;
+ }
+
+ vf->vring[i].irq = irq;
+ }
+
+ return 0;
+}
+
static int ifcvf_start_datapath(void *private)
{
struct ifcvf_hw *vf = ifcvf_private_to_vf(private);
@@ -118,17 +172,34 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
{
struct ifcvf_adapter *adapter;
struct ifcvf_hw *vf;
+ u8 status_old;
+ int ret;

vf = vdpa_to_vf(vdpa_dev);
adapter = dev_get_drvdata(vdpa_dev->dev.parent);
+ status_old = ifcvf_get_status(vf);

- if (status == 0) {
+ if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) &&
+ !(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
ifcvf_stop_datapath(adapter);
+ ifcvf_free_irq(adapter, IFCVF_MAX_QUEUE_PAIRS * 2);
+ }
+
+ if (status == 0) {
ifcvf_reset_vring(adapter);
return;
}

- if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
+ if ((status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+ !(status_old & VIRTIO_CONFIG_S_DRIVER_OK)) {
+ ret = ifcvf_request_irq(adapter);
+ if (ret) {
+ status = ifcvf_get_status(vf);
+ status |= VIRTIO_CONFIG_S_FAILED;
+ ifcvf_set_status(vf, status);
+ return;
+ }
+
if (ifcvf_start_datapath(adapter) < 0)
IFCVF_ERR(adapter->pdev,
"Failed to set ifcvf vdpa status %u\n",
@@ -284,38 +355,6 @@ static void ifcvf_vdpa_set_config_cb(struct vdpa_device *vdpa_dev,
.set_config_cb = ifcvf_vdpa_set_config_cb,
};

-static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
-{
- struct pci_dev *pdev = adapter->pdev;
- struct ifcvf_hw *vf = &adapter->vf;
- int vector, i, ret, irq;
-
-
- for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
- snprintf(vf->vring[i].msix_name, 256, "ifcvf[%s]-%d\n",
- pci_name(pdev), i);
- vector = i + IFCVF_MSI_QUEUE_OFF;
- irq = pci_irq_vector(pdev, vector);
- ret = devm_request_irq(&pdev->dev, irq,
- ifcvf_intr_handler, 0,
- vf->vring[i].msix_name,
- &vf->vring[i]);
- if (ret) {
- IFCVF_ERR(pdev,
- "Failed to request irq for vq %d\n", i);
- return ret;
- }
- vf->vring[i].irq = irq;
- }
-
- return 0;
-}
-
-static void ifcvf_free_irq_vectors(void *data)
-{
- pci_free_irq_vectors(data);
-}
-
static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct device *dev = &pdev->dev;
@@ -349,13 +388,6 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
return ret;
}

- ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
- IFCVF_MAX_INTR, PCI_IRQ_MSIX);
- if (ret < 0) {
- IFCVF_ERR(pdev, "Failed to alloc irq vectors\n");
- return ret;
- }
-
ret = devm_add_action_or_reset(dev, ifcvf_free_irq_vectors, pdev);
if (ret) {
IFCVF_ERR(pdev,
@@ -379,12 +411,6 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
adapter->pdev = pdev;
adapter->vdpa.dma_dev = &pdev->dev;

- ret = ifcvf_request_irq(adapter);
- if (ret) {
- IFCVF_ERR(pdev, "Failed to request MSI-X irq\n");
- goto err;
- }
-
ret = ifcvf_init_hw(vf, pdev);
if (ret) {
IFCVF_ERR(pdev, "Failed to init IFCVF hw\n");
--
1.8.3.1


2020-05-13 04:18:05

by Jason Wang

[permalink] [raw]
Subject: Re: [PATCH V2] ifcvf: move IRQ request/free to status change handlers


On 2020/5/12 下午4:00, Zhu Lingshan wrote:
> This commit move IRQ request and free operations from probe()
> to VIRTIO status change handler to comply with VIRTIO spec.
>
> VIRTIO spec 1.1, section 2.1.2 Device Requirements: Device Status Field
> The device MUST NOT consume buffers or send any used buffer
> notifications to the driver before DRIVER_OK.


This comment needs to be checked as I said previously. It's only needed
if we're sure ifcvf can generate interrupt before DRIVER_OK.


>
> Signed-off-by: Zhu Lingshan <[email protected]>
> ---
> changes from V1:
> remove ifcvf_stop_datapath() in status == 0 handler, we don't need to do this
> twice; handle status == 0 after DRIVER_OK -> !DRIVER_OK handler (Jason Wang)


Patch looks good to me, but with this patch ping cannot work on my
machine. (It works without this patch).

Thanks


>
> drivers/vdpa/ifcvf/ifcvf_main.c | 120 ++++++++++++++++++++++++----------------
> 1 file changed, 73 insertions(+), 47 deletions(-)
>
> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
> index abf6a061..d529ed6 100644
> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
> @@ -28,6 +28,60 @@ static irqreturn_t ifcvf_intr_handler(int irq, void *arg)
> return IRQ_HANDLED;
> }
>
> +static void ifcvf_free_irq_vectors(void *data)
> +{
> + pci_free_irq_vectors(data);
> +}
> +
> +static void ifcvf_free_irq(struct ifcvf_adapter *adapter, int queues)
> +{
> + struct pci_dev *pdev = adapter->pdev;
> + struct ifcvf_hw *vf = &adapter->vf;
> + int i;
> +
> +
> + for (i = 0; i < queues; i++)
> + devm_free_irq(&pdev->dev, vf->vring[i].irq, &vf->vring[i]);
> +
> + ifcvf_free_irq_vectors(pdev);
> +}
> +
> +static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
> +{
> + struct pci_dev *pdev = adapter->pdev;
> + struct ifcvf_hw *vf = &adapter->vf;
> + int vector, i, ret, irq;
> +
> + ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
> + IFCVF_MAX_INTR, PCI_IRQ_MSIX);
> + if (ret < 0) {
> + IFCVF_ERR(pdev, "Failed to alloc IRQ vectors\n");
> + return ret;
> + }
> +
> + for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> + snprintf(vf->vring[i].msix_name, 256, "ifcvf[%s]-%d\n",
> + pci_name(pdev), i);
> + vector = i + IFCVF_MSI_QUEUE_OFF;
> + irq = pci_irq_vector(pdev, vector);
> + ret = devm_request_irq(&pdev->dev, irq,
> + ifcvf_intr_handler, 0,
> + vf->vring[i].msix_name,
> + &vf->vring[i]);
> + if (ret) {
> + IFCVF_ERR(pdev,
> + "Failed to request irq for vq %d\n", i);
> + ifcvf_free_irq(adapter, i);
> +
> + return ret;
> + }
> +
> + vf->vring[i].irq = irq;
> + }
> +
> + return 0;
> +}
> +
> static int ifcvf_start_datapath(void *private)
> {
> struct ifcvf_hw *vf = ifcvf_private_to_vf(private);
> @@ -118,17 +172,34 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
> {
> struct ifcvf_adapter *adapter;
> struct ifcvf_hw *vf;
> + u8 status_old;
> + int ret;
>
> vf = vdpa_to_vf(vdpa_dev);
> adapter = dev_get_drvdata(vdpa_dev->dev.parent);
> + status_old = ifcvf_get_status(vf);
>
> - if (status == 0) {
> + if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) &&
> + !(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
> ifcvf_stop_datapath(adapter);
> + ifcvf_free_irq(adapter, IFCVF_MAX_QUEUE_PAIRS * 2);
> + }
> +
> + if (status == 0) {
> ifcvf_reset_vring(adapter);
> return;
> }
>
> - if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
> + if ((status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> + !(status_old & VIRTIO_CONFIG_S_DRIVER_OK)) {
> + ret = ifcvf_request_irq(adapter);
> + if (ret) {
> + status = ifcvf_get_status(vf);
> + status |= VIRTIO_CONFIG_S_FAILED;
> + ifcvf_set_status(vf, status);
> + return;
> + }
> +
> if (ifcvf_start_datapath(adapter) < 0)
> IFCVF_ERR(adapter->pdev,
> "Failed to set ifcvf vdpa status %u\n",
> @@ -284,38 +355,6 @@ static void ifcvf_vdpa_set_config_cb(struct vdpa_device *vdpa_dev,
> .set_config_cb = ifcvf_vdpa_set_config_cb,
> };
>
> -static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
> -{
> - struct pci_dev *pdev = adapter->pdev;
> - struct ifcvf_hw *vf = &adapter->vf;
> - int vector, i, ret, irq;
> -
> -
> - for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> - snprintf(vf->vring[i].msix_name, 256, "ifcvf[%s]-%d\n",
> - pci_name(pdev), i);
> - vector = i + IFCVF_MSI_QUEUE_OFF;
> - irq = pci_irq_vector(pdev, vector);
> - ret = devm_request_irq(&pdev->dev, irq,
> - ifcvf_intr_handler, 0,
> - vf->vring[i].msix_name,
> - &vf->vring[i]);
> - if (ret) {
> - IFCVF_ERR(pdev,
> - "Failed to request irq for vq %d\n", i);
> - return ret;
> - }
> - vf->vring[i].irq = irq;
> - }
> -
> - return 0;
> -}
> -
> -static void ifcvf_free_irq_vectors(void *data)
> -{
> - pci_free_irq_vectors(data);
> -}
> -
> static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> {
> struct device *dev = &pdev->dev;
> @@ -349,13 +388,6 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> return ret;
> }
>
> - ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
> - IFCVF_MAX_INTR, PCI_IRQ_MSIX);
> - if (ret < 0) {
> - IFCVF_ERR(pdev, "Failed to alloc irq vectors\n");
> - return ret;
> - }
> -
> ret = devm_add_action_or_reset(dev, ifcvf_free_irq_vectors, pdev);
> if (ret) {
> IFCVF_ERR(pdev,
> @@ -379,12 +411,6 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> adapter->pdev = pdev;
> adapter->vdpa.dma_dev = &pdev->dev;
>
> - ret = ifcvf_request_irq(adapter);
> - if (ret) {
> - IFCVF_ERR(pdev, "Failed to request MSI-X irq\n");
> - goto err;
> - }
> -
> ret = ifcvf_init_hw(vf, pdev);
> if (ret) {
> IFCVF_ERR(pdev, "Failed to init IFCVF hw\n");

2020-05-13 05:59:52

by Jason Wang

[permalink] [raw]
Subject: Re: [PATCH V2] ifcvf: move IRQ request/free to status change handlers


On 2020/5/13 下午12:42, Zhu, Lingshan wrote:
>
>
> On 5/13/2020 12:12 PM, Jason Wang wrote:
>>
>> On 2020/5/12 下午4:00, Zhu Lingshan wrote:
>>> This commit move IRQ request and free operations from probe()
>>> to VIRTIO status change handler to comply with VIRTIO spec.
>>>
>>> VIRTIO spec 1.1, section 2.1.2 Device Requirements: Device Status Field
>>> The device MUST NOT consume buffers or send any used buffer
>>> notifications to the driver before DRIVER_OK.
>>
>>
>> This comment needs to be checked as I said previously. It's only
>> needed if we're sure ifcvf can generate interrupt before DRIVER_OK.
>>
>>
>>>
>>> Signed-off-by: Zhu Lingshan <[email protected]>
>>> ---
>>> changes from V1:
>>> remove ifcvf_stop_datapath() in status == 0 handler, we don't need
>>> to do this
>>> twice; handle status == 0 after DRIVER_OK -> !DRIVER_OK handler
>>> (Jason Wang)
>>
>>
>> Patch looks good to me, but with this patch ping cannot work on my
>> machine. (It works without this patch).
>>
>> Thanks
> This is strange, it works on my machines, let's have a check offline.
>
> Thanks,
> BR
> Zhu Lingshan


Note that I tested the patch with vhost-vpda.

Thanks.

2020-05-13 07:20:39

by Jason Wang

[permalink] [raw]
Subject: Re: [PATCH V2] ifcvf: move IRQ request/free to status change handlers


On 2020/5/13 下午12:42, Zhu, Lingshan wrote:
>
>
> On 5/13/2020 12:12 PM, Jason Wang wrote:
>>
>> On 2020/5/12 下午4:00, Zhu Lingshan wrote:
>>> This commit move IRQ request and free operations from probe()
>>> to VIRTIO status change handler to comply with VIRTIO spec.
>>>
>>> VIRTIO spec 1.1, section 2.1.2 Device Requirements: Device Status Field
>>> The device MUST NOT consume buffers or send any used buffer
>>> notifications to the driver before DRIVER_OK.
>>
>>
>> This comment needs to be checked as I said previously. It's only
>> needed if we're sure ifcvf can generate interrupt before DRIVER_OK.
>>
>>
>>>
>>> Signed-off-by: Zhu Lingshan <[email protected]>
>>> ---
>>> changes from V1:
>>> remove ifcvf_stop_datapath() in status == 0 handler, we don't need
>>> to do this
>>> twice; handle status == 0 after DRIVER_OK -> !DRIVER_OK handler
>>> (Jason Wang)
>>
>>
>> Patch looks good to me, but with this patch ping cannot work on my
>> machine. (It works without this patch).
>>
>> Thanks
> This is strange, it works on my machines, let's have a check offline.
>
> Thanks,
> BR
> Zhu Lingshan


I give it a try with virito-vpda and a tiny userspace. Either works.

So it could be an issue of qemu codes.

Let's wait for Cindy to test if it really works.

Thanks


2020-05-19 01:55:20

by Cindy Lu

[permalink] [raw]
Subject: Re: [PATCH V2] ifcvf: move IRQ request/free to status change handlers

Hi ,Jason
It works ok in the latest version of qemu vdpa code , So I think the
patch is ok.
Thanks
Cindy
On Wed, May 13, 2020 at 3:18 PM Jason Wang <[email protected]> wrote:
>
>
> On 2020/5/13 下午12:42, Zhu, Lingshan wrote:
> >
> >
> > On 5/13/2020 12:12 PM, Jason Wang wrote:
> >>
> >> On 2020/5/12 下午4:00, Zhu Lingshan wrote:
> >>> This commit move IRQ request and free operations from probe()
> >>> to VIRTIO status change handler to comply with VIRTIO spec.
> >>>
> >>> VIRTIO spec 1.1, section 2.1.2 Device Requirements: Device Status Field
> >>> The device MUST NOT consume buffers or send any used buffer
> >>> notifications to the driver before DRIVER_OK.
> >>
> >>
> >> This comment needs to be checked as I said previously. It's only
> >> needed if we're sure ifcvf can generate interrupt before DRIVER_OK.
> >>
> >>
> >>>
> >>> Signed-off-by: Zhu Lingshan <[email protected]>
> >>> ---
> >>> changes from V1:
> >>> remove ifcvf_stop_datapath() in status == 0 handler, we don't need
> >>> to do this
> >>> twice; handle status == 0 after DRIVER_OK -> !DRIVER_OK handler
> >>> (Jason Wang)
> >>
> >>
> >> Patch looks good to me, but with this patch ping cannot work on my
> >> machine. (It works without this patch).
> >>
> >> Thanks
> > This is strange, it works on my machines, let's have a check offline.
> >
> > Thanks,
> > BR
> > Zhu Lingshan
>
>
> I give it a try with virito-vpda and a tiny userspace. Either works.
>
> So it could be an issue of qemu codes.
>
> Let's wait for Cindy to test if it really works.
>
> Thanks
>
>

2020-05-19 05:54:35

by Jason Wang

[permalink] [raw]
Subject: Re: [PATCH V2] ifcvf: move IRQ request/free to status change handlers


On 2020/5/19 上午9:51, Cindy Lu wrote:
> Hi ,Jason
> It works ok in the latest version of qemu vdpa code , So I think the
> patch is ok.
> Thanks
> Cindy


Thanks for the testing, (btw, we'd better not do top posting when
discuss in the community).

So,

Acked-by: Jason Wang <[email protected]>



> On Wed, May 13, 2020 at 3:18 PM Jason Wang <[email protected]> wrote:
>>
>> On 2020/5/13 下午12:42, Zhu, Lingshan wrote:
>>>
>>> On 5/13/2020 12:12 PM, Jason Wang wrote:
>>>> On 2020/5/12 下午4:00, Zhu Lingshan wrote:
>>>>> This commit move IRQ request and free operations from probe()
>>>>> to VIRTIO status change handler to comply with VIRTIO spec.
>>>>>
>>>>> VIRTIO spec 1.1, section 2.1.2 Device Requirements: Device Status Field
>>>>> The device MUST NOT consume buffers or send any used buffer
>>>>> notifications to the driver before DRIVER_OK.
>>>>
>>>> This comment needs to be checked as I said previously. It's only
>>>> needed if we're sure ifcvf can generate interrupt before DRIVER_OK.
>>>>
>>>>
>>>>> Signed-off-by: Zhu Lingshan <[email protected]>
>>>>> ---
>>>>> changes from V1:
>>>>> remove ifcvf_stop_datapath() in status == 0 handler, we don't need
>>>>> to do this
>>>>> twice; handle status == 0 after DRIVER_OK -> !DRIVER_OK handler
>>>>> (Jason Wang)
>>>>
>>>> Patch looks good to me, but with this patch ping cannot work on my
>>>> machine. (It works without this patch).
>>>>
>>>> Thanks
>>> This is strange, it works on my machines, let's have a check offline.
>>>
>>> Thanks,
>>> BR
>>> Zhu Lingshan
>>
>> I give it a try with virito-vpda and a tiny userspace. Either works.
>>
>> So it could be an issue of qemu codes.
>>
>> Let's wait for Cindy to test if it really works.
>>
>> Thanks
>>
>>