thr3ads.net - Linux Virtualization - automatic IRQ affinity for virtio [Nov 2016]

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Christoph Hellwig

2016-Nov-17 10:43 UTC

automatic IRQ affinity for virtio

Hi Michael,

this series contains a couple cleanups for the virtio_pci interrupt
handling code, including a switch to the new pci_irq_alloc_vectors
helper, and support for automatic affinity by the PCI layer if the
consumers ask for it.  It then converts over virtio_blk to use this
functionality so that it's blk-mq queues are aligned to the MSI-X
vector routing.  I have a similar patch in the queue for virtio-scsi,
but that would require pulling in the SCSI tree, so I'm not sure if
you'd like it for this window, but if you do I can send it in another
series.  The third driver using per-CPU virtqueues is virtio_net,
but that will take some more time as I haven't started work on the
networking infrastructure yet.

Note that these patches require core IRQ changes from a stable
branch in the tip tree to be pulled in first:

	git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git irq/for-block

Gitweb:

	https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/log/?h=irq/for-block

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 01/11] virtio_pci: use pci_alloc_irq_vectors

This avoids the separate allocation for the msix_entries structures, and
instead allows us to use pci_irq_vector to find a given IRQ vector.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 42 +++++++++++++++-----------------------
 drivers/virtio/virtio_pci_common.h |  1 -
 2 files changed, 17 insertions(+), 26 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index d9a9058..f5e2751 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -37,7 +37,7 @@ void vp_synchronize_vectors(struct virtio_device *vdev)
 		synchronize_irq(vp_dev->pci_dev->irq);
 
 	for (i = 0; i < vp_dev->msix_vectors; ++i)
-		synchronize_irq(vp_dev->msix_entries[i].vector);
+		synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i));
 }
 
 /* the notify function used when creating a virt queue */
@@ -113,7 +113,7 @@ static void vp_free_vectors(struct virtio_device *vdev)
 	}
 
 	for (i = 0; i < vp_dev->msix_used_vectors; ++i)
-		free_irq(vp_dev->msix_entries[i].vector, vp_dev);
+		free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);
 
 	for (i = 0; i < vp_dev->msix_vectors; i++)
 		if (vp_dev->msix_affinity_masks[i])
@@ -123,7 +123,7 @@ static void vp_free_vectors(struct virtio_device *vdev)
 		/* Disable the vector used for configuration */
 		vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);
 
-		pci_disable_msix(vp_dev->pci_dev);
+		pci_free_irq_vectors(vp_dev->pci_dev);
 		vp_dev->msix_enabled = 0;
 	}
 
@@ -131,8 +131,6 @@ static void vp_free_vectors(struct virtio_device *vdev)
 	vp_dev->msix_used_vectors = 0;
 	kfree(vp_dev->msix_names);
 	vp_dev->msix_names = NULL;
-	kfree(vp_dev->msix_entries);
-	vp_dev->msix_entries = NULL;
 	kfree(vp_dev->msix_affinity_masks);
 	vp_dev->msix_affinity_masks = NULL;
 }
@@ -147,10 +145,6 @@ static int vp_request_msix_vectors(struct virtio_device
*vdev, int nvectors,
 
 	vp_dev->msix_vectors = nvectors;
 
-	vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries,
-				       GFP_KERNEL);
-	if (!vp_dev->msix_entries)
-		goto error;
 	vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
 				     GFP_KERNEL);
 	if (!vp_dev->msix_names)
@@ -165,12 +159,9 @@ static int vp_request_msix_vectors(struct virtio_device
*vdev, int nvectors,
 					GFP_KERNEL))
 			goto error;
 
-	for (i = 0; i < nvectors; ++i)
-		vp_dev->msix_entries[i].entry = i;
-
-	err = pci_enable_msix_exact(vp_dev->pci_dev,
-				    vp_dev->msix_entries, nvectors);
-	if (err)
+	err = pci_alloc_irq_vectors(vp_dev->pci_dev, nvectors, nvectors,
+			PCI_IRQ_MSIX);
+	if (err < 0)
 		goto error;
 	vp_dev->msix_enabled = 1;
 
@@ -178,7 +169,7 @@ static int vp_request_msix_vectors(struct virtio_device
*vdev, int nvectors,
 	v = vp_dev->msix_used_vectors;
 	snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
 		 "%s-config", name);
-	err = request_irq(vp_dev->msix_entries[v].vector,
+	err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
 			  vp_config_changed, 0, vp_dev->msix_names[v],
 			  vp_dev);
 	if (err)
@@ -197,7 +188,7 @@ static int vp_request_msix_vectors(struct virtio_device
*vdev, int nvectors,
 		v = vp_dev->msix_used_vectors;
 		snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
 			 "%s-virtqueues", name);
-		err = request_irq(vp_dev->msix_entries[v].vector,
+		err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
 				  vp_vring_interrupt, 0, vp_dev->msix_names[v],
 				  vp_dev);
 		if (err)
@@ -276,14 +267,15 @@ void vp_del_vqs(struct virtio_device *vdev)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	struct virtqueue *vq, *n;
-	struct virtio_pci_vq_info *info;
 
 	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
-		info = vp_dev->vqs[vq->index];
-		if (vp_dev->per_vq_vectors &&
-			info->msix_vector != VIRTIO_MSI_NO_VECTOR)
-			free_irq(vp_dev->msix_entries[info->msix_vector].vector,
-				 vq);
+		if (vp_dev->per_vq_vectors) {
+			int v = vp_dev->vqs[vq->index]->msix_vector;
+
+			if (v != VIRTIO_MSI_NO_VECTOR)
+				free_irq(pci_irq_vector(vp_dev->pci_dev, v),
+					vq);
+		}
 		vp_del_vq(vq);
 	}
 	vp_dev->per_vq_vectors = false;
@@ -356,7 +348,7 @@ static int vp_try_to_find_vqs(struct virtio_device *vdev,
unsigned nvqs,
 			 sizeof *vp_dev->msix_names,
 			 "%s-%s",
 			 dev_name(&vp_dev->vdev.dev), names[i]);
-		err = request_irq(vp_dev->msix_entries[msix_vec].vector,
+		err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec),
 				  vring_interrupt, 0,
 				  vp_dev->msix_names[msix_vec],
 				  vqs[i]);
@@ -419,7 +411,7 @@ int vp_set_vq_affinity(struct virtqueue *vq, int cpu)
 
 	if (vp_dev->msix_enabled) {
 		mask = vp_dev->msix_affinity_masks[info->msix_vector];
-		irq = vp_dev->msix_entries[info->msix_vector].vector;
+		irq = pci_irq_vector(vp_dev->pci_dev, info->msix_vector);
 		if (cpu == -1)
 			irq_set_affinity_hint(irq, NULL);
 		else {
diff --git a/drivers/virtio/virtio_pci_common.h
b/drivers/virtio/virtio_pci_common.h
index 2826320..b2f6662 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -85,7 +85,6 @@ struct virtio_pci_device {
 	/* MSI-X support */
 	int msix_enabled;
 	int intx_enabled;
-	struct msix_entry *msix_entries;
 	cpumask_var_t *msix_affinity_masks;
 	/* Name strings for interrupts. This size should be enough,
 	 * and I'm too lazy to allocate each name separately. */
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 02/11] virtio_pci: remove the call to vp_free_vectors in vp_request_msix_vectors

vp_request_msix_vectors is only called by vp_try_to_find_vqs, which already
calls vp_free_vectors through vp_del_vqs in the failure case.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index f5e2751..93700c5 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -197,7 +197,6 @@ static int vp_request_msix_vectors(struct virtio_device
*vdev, int nvectors,
 	}
 	return 0;
 error:
-	vp_free_vectors(vdev);
 	return err;
 }
 
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 03/11] virtio_pci: merge vp_free_vectors into vp_del_vqs

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 61 +++++++++++++++++---------------------
 1 file changed, 27 insertions(+), 34 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index 93700c5..f6c5499 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -102,39 +102,6 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
 	return vp_vring_interrupt(irq, opaque);
 }
 
-static void vp_free_vectors(struct virtio_device *vdev)
-{
-	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
-	int i;
-
-	if (vp_dev->intx_enabled) {
-		free_irq(vp_dev->pci_dev->irq, vp_dev);
-		vp_dev->intx_enabled = 0;
-	}
-
-	for (i = 0; i < vp_dev->msix_used_vectors; ++i)
-		free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);
-
-	for (i = 0; i < vp_dev->msix_vectors; i++)
-		if (vp_dev->msix_affinity_masks[i])
-			free_cpumask_var(vp_dev->msix_affinity_masks[i]);
-
-	if (vp_dev->msix_enabled) {
-		/* Disable the vector used for configuration */
-		vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);
-
-		pci_free_irq_vectors(vp_dev->pci_dev);
-		vp_dev->msix_enabled = 0;
-	}
-
-	vp_dev->msix_vectors = 0;
-	vp_dev->msix_used_vectors = 0;
-	kfree(vp_dev->msix_names);
-	vp_dev->msix_names = NULL;
-	kfree(vp_dev->msix_affinity_masks);
-	vp_dev->msix_affinity_masks = NULL;
-}
-
 static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
 				   bool per_vq_vectors)
 {
@@ -266,6 +233,7 @@ void vp_del_vqs(struct virtio_device *vdev)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	struct virtqueue *vq, *n;
+	int i;
 
 	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
 		if (vp_dev->per_vq_vectors) {
@@ -279,7 +247,32 @@ void vp_del_vqs(struct virtio_device *vdev)
 	}
 	vp_dev->per_vq_vectors = false;
 
-	vp_free_vectors(vdev);
+	if (vp_dev->intx_enabled) {
+		free_irq(vp_dev->pci_dev->irq, vp_dev);
+		vp_dev->intx_enabled = 0;
+	}
+
+	for (i = 0; i < vp_dev->msix_used_vectors; ++i)
+		free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);
+
+	for (i = 0; i < vp_dev->msix_vectors; i++)
+		if (vp_dev->msix_affinity_masks[i])
+			free_cpumask_var(vp_dev->msix_affinity_masks[i]);
+
+	if (vp_dev->msix_enabled) {
+		/* Disable the vector used for configuration */
+		vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);
+
+		pci_free_irq_vectors(vp_dev->pci_dev);
+		vp_dev->msix_enabled = 0;
+	}
+
+	vp_dev->msix_vectors = 0;
+	vp_dev->msix_used_vectors = 0;
+	kfree(vp_dev->msix_names);
+	vp_dev->msix_names = NULL;
+	kfree(vp_dev->msix_affinity_masks);
+	vp_dev->msix_affinity_masks = NULL;
 	kfree(vp_dev->vqs);
 	vp_dev->vqs = NULL;
 }
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 04/11] virtio_pci: split vp_try_to_find_vqs into INTx and MSI-X variants

There is basically no shared logic between the INTx and MSI-X case in
vp_try_to_find_vqs, so split the function into two and clean them up
a little bit.

Also remove the fairly pointless vp_request_intx wrapper while we're at it.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 97 ++++++++++++++++++++++----------------
 1 file changed, 57 insertions(+), 40 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index f6c5499..9a9826e 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -167,18 +167,6 @@ static int vp_request_msix_vectors(struct virtio_device
*vdev, int nvectors,
 	return err;
 }
 
-static int vp_request_intx(struct virtio_device *vdev)
-{
-	int err;
-	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
-
-	err = request_irq(vp_dev->pci_dev->irq, vp_interrupt,
-			  IRQF_SHARED, dev_name(&vdev->dev), vp_dev);
-	if (!err)
-		vp_dev->intx_enabled = 1;
-	return err;
-}
-
 static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned
index,
 				     void (*callback)(struct virtqueue *vq),
 				     const char *name,
@@ -277,50 +265,44 @@ void vp_del_vqs(struct virtio_device *vdev)
 	vp_dev->vqs = NULL;
 }
 
-static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
 			      struct virtqueue *vqs[],
 			      vq_callback_t *callbacks[],
 			      const char * const names[],
-			      bool use_msix,
 			      bool per_vq_vectors)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	u16 msix_vec;
 	int i, err, nvectors, allocated_vectors;
 
-	vp_dev->vqs = kmalloc(nvqs * sizeof *vp_dev->vqs, GFP_KERNEL);
+	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
 	if (!vp_dev->vqs)
 		return -ENOMEM;
 
-	if (!use_msix) {
-		/* Old style: one normal interrupt for change and all vqs. */
-		err = vp_request_intx(vdev);
-		if (err)
-			goto error_find;
+	if (per_vq_vectors) {
+		/* Best option: one for change interrupt, one per vq. */
+		nvectors = 1;
+		for (i = 0; i < nvqs; ++i)
+			if (callbacks[i])
+				++nvectors;
 	} else {
-		if (per_vq_vectors) {
-			/* Best option: one for change interrupt, one per vq. */
-			nvectors = 1;
-			for (i = 0; i < nvqs; ++i)
-				if (callbacks[i])
-					++nvectors;
-		} else {
-			/* Second best: one for change, shared for all vqs. */
-			nvectors = 2;
-		}
-
-		err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors);
-		if (err)
-			goto error_find;
+		/* Second best: one for change, shared for all vqs. */
+		nvectors = 2;
 	}
 
+	err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors);
+	if (err)
+		goto error_find;
+
 	vp_dev->per_vq_vectors = per_vq_vectors;
 	allocated_vectors = vp_dev->msix_used_vectors;
 	for (i = 0; i < nvqs; ++i) {
 		if (!names[i]) {
 			vqs[i] = NULL;
 			continue;
-		} else if (!callbacks[i] || !vp_dev->msix_enabled)
+		}
+
+		if (!callbacks[i])
 			msix_vec = VIRTIO_MSI_NO_VECTOR;
 		else if (vp_dev->per_vq_vectors)
 			msix_vec = allocated_vectors++;
@@ -356,6 +338,43 @@ static int vp_try_to_find_vqs(struct virtio_device *vdev,
unsigned nvqs,
 	return err;
 }
 
+static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs,
+		struct virtqueue *vqs[], vq_callback_t *callbacks[],
+		const char * const names[])
+{
+	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+	int i, err;
+
+	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
+	if (!vp_dev->vqs)
+		return -ENOMEM;
+
+	err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
+			dev_name(&vdev->dev), vp_dev);
+	if (err)
+		goto out_del_vqs;
+
+	vp_dev->intx_enabled = 1;
+	vp_dev->per_vq_vectors = false;
+	for (i = 0; i < nvqs; ++i) {
+		if (!names[i]) {
+			vqs[i] = NULL;
+			continue;
+		}
+		vqs[i] = vp_setup_vq(vdev, i, callbacks[i], names[i],
+				VIRTIO_MSI_NO_VECTOR);
+		if (IS_ERR(vqs[i])) {
+			err = PTR_ERR(vqs[i]);
+			goto out_del_vqs;
+		}
+	}
+
+	return 0;
+out_del_vqs:
+	vp_del_vqs(vdev);
+	return err;
+}
+
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		struct virtqueue *vqs[],
@@ -365,17 +384,15 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 	int err;
 
 	/* Try MSI-X with one vector per queue. */
-	err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true);
+	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, true);
 	if (!err)
 		return 0;
 	/* Fallback: MSI-X with one vector for config, one shared for queues. */
-	err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
-				 true, false);
+	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, false);
 	if (!err)
 		return 0;
 	/* Finally fall back to regular interrupts. */
-	return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
-				  false, false);
+	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names);
 }
 
 const char *vp_bus_name(struct virtio_device *vdev)
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 05/11] virtio_pci: use shared interrupts for virtqueues

This lets IRQ layer handle dispatching IRQs to separate handlers for the
case where we don't have per-VQ MSI-X vectors, and allows us to greatly
simplify the code based on the assumption that we always have interrupt
vector 0 (legacy INTx or config interrupt for MSI-X) available, and
any other interrupt is request/freed throught the VQ, even if the
actual interrupt line might be shared in some cases.

This allows removing a great deal of variables keeping track of the
interrupt state in struct virtio_pci_device, as we can now simply walk the
list of VQs and deal with per-VQ interrupt handlers there, and only treat
vector 0 special.  As a little caveat this means we have to check if VQs
have been set up before calling vp_synchronize_vectors, as otherwise
the initial reset will trip over the uninitialized ->vqs array.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 95 ++++++++++++++------------------------
 drivers/virtio/virtio_pci_common.h | 18 +-------
 2 files changed, 36 insertions(+), 77 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index 9a9826e..9e6c9d8 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -31,13 +31,18 @@ MODULE_PARM_DESC(force_legacy,
 void vp_synchronize_vectors(struct virtio_device *vdev)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
-	int i;
+	struct virtqueue *vq, *n;
+
+	if (!vp_dev->vqs)
+		return;
 
-	if (vp_dev->intx_enabled)
-		synchronize_irq(vp_dev->pci_dev->irq);
+	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
+		int vec = vp_dev->vqs[vq->index]->msix_vector;
+		if (vec != VIRTIO_MSI_NO_VECTOR)
+			synchronize_irq(pci_irq_vector(vp_dev->pci_dev, vec));
+	}
 
-	for (i = 0; i < vp_dev->msix_vectors; ++i)
-		synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i));
+	synchronize_irq(pci_irq_vector(vp_dev->pci_dev, 0));
 }
 
 /* the notify function used when creating a virt queue */
@@ -102,16 +107,14 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
 	return vp_vring_interrupt(irq, opaque);
 }
 
-static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
-				   bool per_vq_vectors)
+static int vp_setup_msix_vectors(struct virtio_device *vdev, int nvectors)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	const char *name = dev_name(&vp_dev->vdev.dev);
-	unsigned i, v;
+	unsigned i;
 	int err = -ENOMEM;
 
 	vp_dev->msix_vectors = nvectors;
-
 	vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
 				     GFP_KERNEL);
 	if (!vp_dev->msix_names)
@@ -133,35 +136,20 @@ static int vp_request_msix_vectors(struct virtio_device
*vdev, int nvectors,
 	vp_dev->msix_enabled = 1;
 
 	/* Set the vector used for configuration */
-	v = vp_dev->msix_used_vectors;
-	snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
+	snprintf(vp_dev->msix_names[0], sizeof(*vp_dev->msix_names),
 		 "%s-config", name);
-	err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
-			  vp_config_changed, 0, vp_dev->msix_names[v],
+	err = request_irq(pci_irq_vector(vp_dev->pci_dev, 0),
+			  vp_config_changed, 0, vp_dev->msix_names[0],
 			  vp_dev);
 	if (err)
 		goto error;
-	++vp_dev->msix_used_vectors;
 
-	v = vp_dev->config_vector(vp_dev, v);
 	/* Verify we had enough resources to assign the vector */
-	if (v == VIRTIO_MSI_NO_VECTOR) {
+	if (vp_dev->config_vector(vp_dev, 0) == VIRTIO_MSI_NO_VECTOR) {
 		err = -EBUSY;
 		goto error;
 	}
 
-	if (!per_vq_vectors) {
-		/* Shared vector for all VQs */
-		v = vp_dev->msix_used_vectors;
-		snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
-			 "%s-virtqueues", name);
-		err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
-				  vp_vring_interrupt, 0, vp_dev->msix_names[v],
-				  vp_dev);
-		if (err)
-			goto error;
-		++vp_dev->msix_used_vectors;
-	}
 	return 0;
 error:
 	return err;
@@ -224,24 +212,14 @@ void vp_del_vqs(struct virtio_device *vdev)
 	int i;
 
 	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
-		if (vp_dev->per_vq_vectors) {
-			int v = vp_dev->vqs[vq->index]->msix_vector;
+		int vec = vp_dev->vqs[vq->index]->msix_vector;
 
-			if (v != VIRTIO_MSI_NO_VECTOR)
-				free_irq(pci_irq_vector(vp_dev->pci_dev, v),
-					vq);
-		}
+		if (vec != VIRTIO_MSI_NO_VECTOR)
+			free_irq(pci_irq_vector(vp_dev->pci_dev, vec), vq);
 		vp_del_vq(vq);
 	}
-	vp_dev->per_vq_vectors = false;
-
-	if (vp_dev->intx_enabled) {
-		free_irq(vp_dev->pci_dev->irq, vp_dev);
-		vp_dev->intx_enabled = 0;
-	}
 
-	for (i = 0; i < vp_dev->msix_used_vectors; ++i)
-		free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);
+	free_irq(pci_irq_vector(vp_dev->pci_dev, 0), vp_dev);
 
 	for (i = 0; i < vp_dev->msix_vectors; i++)
 		if (vp_dev->msix_affinity_masks[i])
@@ -256,7 +234,6 @@ void vp_del_vqs(struct virtio_device *vdev)
 	}
 
 	vp_dev->msix_vectors = 0;
-	vp_dev->msix_used_vectors = 0;
 	kfree(vp_dev->msix_names);
 	vp_dev->msix_names = NULL;
 	kfree(vp_dev->msix_affinity_masks);
@@ -273,7 +250,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev,
unsigned nvqs,
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	u16 msix_vec;
-	int i, err, nvectors, allocated_vectors;
+	int i, err, allocated_vectors, nvectors;
 
 	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
 	if (!vp_dev->vqs)
@@ -290,46 +267,44 @@ static int vp_find_vqs_msix(struct virtio_device *vdev,
unsigned nvqs,
 		nvectors = 2;
 	}
 
-	err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors);
+	err = vp_setup_msix_vectors(vdev, nvectors);
 	if (err)
 		goto error_find;
 
-	vp_dev->per_vq_vectors = per_vq_vectors;
-	allocated_vectors = vp_dev->msix_used_vectors;
+	allocated_vectors = 1; /* vector 0 is the config interrupt */
 	for (i = 0; i < nvqs; ++i) {
 		if (!names[i]) {
 			vqs[i] = NULL;
 			continue;
 		}
 
-		if (!callbacks[i])
-			msix_vec = VIRTIO_MSI_NO_VECTOR;
-		else if (vp_dev->per_vq_vectors)
-			msix_vec = allocated_vectors++;
+		if (callbacks[i])
+			msix_vec = allocated_vectors;
 		else
-			msix_vec = VP_MSIX_VQ_VECTOR;
+			msix_vec = VIRTIO_MSI_NO_VECTOR;
+
 		vqs[i] = vp_setup_vq(vdev, i, callbacks[i], names[i], msix_vec);
 		if (IS_ERR(vqs[i])) {
 			err = PTR_ERR(vqs[i]);
 			goto error_find;
 		}
 
-		if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR)
+		if (msix_vec == VIRTIO_MSI_NO_VECTOR)
 			continue;
 
-		/* allocate per-vq irq if available and necessary */
 		snprintf(vp_dev->msix_names[msix_vec],
-			 sizeof *vp_dev->msix_names,
-			 "%s-%s",
+			 sizeof(*vp_dev->msix_names), "%s-%s",
 			 dev_name(&vp_dev->vdev.dev), names[i]);
 		err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec),
-				  vring_interrupt, 0,
-				  vp_dev->msix_names[msix_vec],
-				  vqs[i]);
+				  vring_interrupt, IRQF_SHARED,
+				  vp_dev->msix_names[msix_vec], vqs[i]);
 		if (err) {
 			vp_del_vq(vqs[i]);
 			goto error_find;
 		}
+
+		if (per_vq_vectors)
+			allocated_vectors++;
 	}
 	return 0;
 
@@ -354,8 +329,6 @@ static int vp_find_vqs_intx(struct virtio_device *vdev,
unsigned nvqs,
 	if (err)
 		goto out_del_vqs;
 
-	vp_dev->intx_enabled = 1;
-	vp_dev->per_vq_vectors = false;
 	for (i = 0; i < nvqs; ++i) {
 		if (!names[i]) {
 			vqs[i] = NULL;
diff --git a/drivers/virtio/virtio_pci_common.h
b/drivers/virtio/virtio_pci_common.h
index b2f6662..93f3e4f 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -84,18 +84,12 @@ struct virtio_pci_device {
 
 	/* MSI-X support */
 	int msix_enabled;
-	int intx_enabled;
 	cpumask_var_t *msix_affinity_masks;
 	/* Name strings for interrupts. This size should be enough,
 	 * and I'm too lazy to allocate each name separately. */
 	char (*msix_names)[256];
-	/* Number of available vectors */
-	unsigned msix_vectors;
-	/* Vectors allocated, excluding per-vq vectors if any */
-	unsigned msix_used_vectors;
-
-	/* Whether we have vector per vq */
-	bool per_vq_vectors;
+	/* Total Number of MSI-X vectors (including per-VQ ones). */
+	int msix_vectors;
 
 	struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev,
 				      struct virtio_pci_vq_info *info,
@@ -108,14 +102,6 @@ struct virtio_pci_device {
 	u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector);
 };
 
-/* Constants for MSI-X */
-/* Use first vector for configuration changes, second and the rest for
- * virtqueues Thus, we need at least 2 vectors for MSI. */
-enum {
-	VP_MSIX_CONFIG_VECTOR = 0,
-	VP_MSIX_VQ_VECTOR = 1,
-};
-
 /* Convert a generic virtio device to our structure */
 static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
 {
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 06/11] virtio_pci: use msix_enable flag in struct pci_dev

Instead of duplicating it.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 7 ++-----
 drivers/virtio/virtio_pci_common.h | 2 --
 drivers/virtio/virtio_pci_legacy.c | 2 +-
 drivers/virtio/virtio_pci_modern.c | 2 +-
 include/uapi/linux/virtio_pci.h    | 2 +-
 5 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index 9e6c9d8..03d3a3b 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -133,7 +133,6 @@ static int vp_setup_msix_vectors(struct virtio_device *vdev,
int nvectors)
 			PCI_IRQ_MSIX);
 	if (err < 0)
 		goto error;
-	vp_dev->msix_enabled = 1;
 
 	/* Set the vector used for configuration */
 	snprintf(vp_dev->msix_names[0], sizeof(*vp_dev->msix_names),
@@ -225,12 +224,10 @@ void vp_del_vqs(struct virtio_device *vdev)
 		if (vp_dev->msix_affinity_masks[i])
 			free_cpumask_var(vp_dev->msix_affinity_masks[i]);
 
-	if (vp_dev->msix_enabled) {
+	if (vp_dev->pci_dev->msix_enabled) {
 		/* Disable the vector used for configuration */
 		vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);
-
 		pci_free_irq_vectors(vp_dev->pci_dev);
-		vp_dev->msix_enabled = 0;
 	}
 
 	vp_dev->msix_vectors = 0;
@@ -391,7 +388,7 @@ int vp_set_vq_affinity(struct virtqueue *vq, int cpu)
 	if (!vq->callback)
 		return -EINVAL;
 
-	if (vp_dev->msix_enabled) {
+	if (vp_dev->pci_dev->msix_enabled) {
 		mask = vp_dev->msix_affinity_masks[info->msix_vector];
 		irq = pci_irq_vector(vp_dev->pci_dev, info->msix_vector);
 		if (cpu == -1)
diff --git a/drivers/virtio/virtio_pci_common.h
b/drivers/virtio/virtio_pci_common.h
index 93f3e4f..d041cce 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -82,8 +82,6 @@ struct virtio_pci_device {
 	/* array of all queues for house-keeping */
 	struct virtio_pci_vq_info **vqs;
 
-	/* MSI-X support */
-	int msix_enabled;
 	cpumask_var_t *msix_affinity_masks;
 	/* Name strings for interrupts. This size should be enough,
 	 * and I'm too lazy to allocate each name separately. */
diff --git a/drivers/virtio/virtio_pci_legacy.c
b/drivers/virtio/virtio_pci_legacy.c
index 6d9e517..f83829f 100644
--- a/drivers/virtio/virtio_pci_legacy.c
+++ b/drivers/virtio/virtio_pci_legacy.c
@@ -169,7 +169,7 @@ static void del_vq(struct virtio_pci_vq_info *info)
 
 	iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
 
-	if (vp_dev->msix_enabled) {
+	if (vp_dev->pci_dev->msix_enabled) {
 		iowrite16(VIRTIO_MSI_NO_VECTOR,
 			  vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
 		/* Flush the write out to device */
diff --git a/drivers/virtio/virtio_pci_modern.c
b/drivers/virtio/virtio_pci_modern.c
index e76bd91..e18d0b0 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -416,7 +416,7 @@ static void del_vq(struct virtio_pci_vq_info *info)
 
 	vp_iowrite16(vq->index, &vp_dev->common->queue_select);
 
-	if (vp_dev->msix_enabled) {
+	if (vp_dev->pci_dev->msix_enabled) {
 		vp_iowrite16(VIRTIO_MSI_NO_VECTOR,
 			     &vp_dev->common->queue_msix_vector);
 		/* Flush the write out to device */
diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h
index 90007a1..15b4385 100644
--- a/include/uapi/linux/virtio_pci.h
+++ b/include/uapi/linux/virtio_pci.h
@@ -79,7 +79,7 @@
  * configuration space */
 #define VIRTIO_PCI_CONFIG_OFF(msix_enabled)	((msix_enabled) ? 24 : 20)
 /* Deprecated: please use VIRTIO_PCI_CONFIG_OFF instead */
-#define VIRTIO_PCI_CONFIG(dev)	VIRTIO_PCI_CONFIG_OFF((dev)->msix_enabled)
+#define VIRTIO_PCI_CONFIG(dev)
VIRTIO_PCI_CONFIG_OFF((dev)->pci_dev->msix_enabled)
 
 /* Virtio ABI version, this must match exactly */
 #define VIRTIO_PCI_ABI_VERSION		0
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 07/11] virtio_pci: simplify MSI-X setup

Try to grab the MSI-X vectors early and fall back to the shared one
before doing tons of allocations.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 52 +++++++++++++++++++-------------------
 1 file changed, 26 insertions(+), 26 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index 03d3a3b..90d7975 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -114,6 +114,18 @@ static int vp_setup_msix_vectors(struct virtio_device
*vdev, int nvectors)
 	unsigned i;
 	int err = -ENOMEM;
 
+	/* Try one vector per queue first. */
+	err = pci_alloc_irq_vectors(vp_dev->pci_dev, nvectors, nvectors,
+			PCI_IRQ_MSIX);
+	if (err < 0) {
+		/* Fallback to one vector for config, one shared for queues. */
+		err = pci_alloc_irq_vectors(vp_dev->pci_dev, 2, 2,
+				PCI_IRQ_MSIX);
+		if (err < 0)
+			goto error;
+		nvectors = 2;
+	}
+
 	vp_dev->msix_vectors = nvectors;
 	vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
 				     GFP_KERNEL);
@@ -129,11 +141,6 @@ static int vp_setup_msix_vectors(struct virtio_device
*vdev, int nvectors)
 					GFP_KERNEL))
 			goto error;
 
-	err = pci_alloc_irq_vectors(vp_dev->pci_dev, nvectors, nvectors,
-			PCI_IRQ_MSIX);
-	if (err < 0)
-		goto error;
-
 	/* Set the vector used for configuration */
 	snprintf(vp_dev->msix_names[0], sizeof(*vp_dev->msix_names),
 		 "%s-config", name);
@@ -149,7 +156,7 @@ static int vp_setup_msix_vectors(struct virtio_device *vdev,
int nvectors)
 		goto error;
 	}
 
-	return 0;
+	return nvectors;
 error:
 	return err;
 }
@@ -242,8 +249,7 @@ void vp_del_vqs(struct virtio_device *vdev)
 static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
 			      struct virtqueue *vqs[],
 			      vq_callback_t *callbacks[],
-			      const char * const names[],
-			      bool per_vq_vectors)
+			      const char * const names[])
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	u16 msix_vec;
@@ -253,20 +259,16 @@ static int vp_find_vqs_msix(struct virtio_device *vdev,
unsigned nvqs,
 	if (!vp_dev->vqs)
 		return -ENOMEM;
 
-	if (per_vq_vectors) {
-		/* Best option: one for change interrupt, one per vq. */
-		nvectors = 1;
-		for (i = 0; i < nvqs; ++i)
-			if (callbacks[i])
-				++nvectors;
-	} else {
-		/* Second best: one for change, shared for all vqs. */
-		nvectors = 2;
+	nvectors = 1;
+	for (i = 0; i < nvqs; i++) {
+		if (callbacks[i])
+			nvectors++;
 	}
 
 	err = vp_setup_msix_vectors(vdev, nvectors);
-	if (err)
+	if (err < 0)
 		goto error_find;
+	nvectors = err;
 
 	allocated_vectors = 1; /* vector 0 is the config interrupt */
 	for (i = 0; i < nvqs; ++i) {
@@ -300,7 +302,11 @@ static int vp_find_vqs_msix(struct virtio_device *vdev,
unsigned nvqs,
 			goto error_find;
 		}
 
-		if (per_vq_vectors)
+		/*
+		 * Use a different vector for each queue if they are available,
+		 * else share the same vector for all VQs.
+		 */
+		if (nvectors == nvqs + 1)
 			allocated_vectors++;
 	}
 	return 0;
@@ -353,15 +359,9 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 {
 	int err;
 
-	/* Try MSI-X with one vector per queue. */
-	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, true);
-	if (!err)
-		return 0;
-	/* Fallback: MSI-X with one vector for config, one shared for queues. */
-	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, false);
+	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names);
 	if (!err)
 		return 0;
-	/* Finally fall back to regular interrupts. */
 	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names);
 }
 
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 08/11] virtio: allow drivers to request IRQ affinity when creating VQs

Add a struct irq_affinity pointer to the find_vqs methods, which if set
is used to tell the PCI layer to create the MSI-X vectors for our I/O
virtqueues with the proper affinity from the start.  Compared to after
the fact affinity hints this gives us an instantly working setup and
allows to allocate the irq descritors node-local and avoid interconnect
traffic.  Last but not least this will allow blk-mq queues are created
based on the interrupt affinity for storage drivers.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/block/virtio_blk.c             |  3 ++-
 drivers/char/virtio_console.c          |  2 +-
 drivers/gpu/drm/virtio/virtgpu_kms.c   |  2 +-
 drivers/misc/mic/vop/vop_main.c        |  2 +-
 drivers/net/caif/caif_virtio.c         |  3 ++-
 drivers/net/virtio_net.c               |  2 +-
 drivers/remoteproc/remoteproc_virtio.c |  3 ++-
 drivers/rpmsg/virtio_rpmsg_bus.c       |  2 +-
 drivers/s390/virtio/kvm_virtio.c       |  3 ++-
 drivers/s390/virtio/virtio_ccw.c       |  3 ++-
 drivers/scsi/virtio_scsi.c             |  3 ++-
 drivers/virtio/virtio_balloon.c        |  3 ++-
 drivers/virtio/virtio_input.c          |  3 ++-
 drivers/virtio/virtio_mmio.c           |  3 ++-
 drivers/virtio/virtio_pci_common.c     | 31 +++++++++++++++++--------------
 drivers/virtio/virtio_pci_common.h     |  5 ++---
 drivers/virtio/virtio_pci_modern.c     |  7 +++----
 include/linux/virtio_config.h          |  9 +++++----
 net/vmw_vsock/virtio_transport.c       |  3 ++-
 19 files changed, 52 insertions(+), 40 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 5545a67..689e790 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -409,7 +409,8 @@ static int init_vq(struct virtio_blk *vblk)
 	}
 
 	/* Discover virtqueues and write information to configuration.  */
-	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names);
+	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
+			NULL);
 	if (err)
 		goto out;
 
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 5649234..18d0681 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1939,7 +1939,7 @@ static int init_vqs(struct ports_device *portdev)
 	/* Find the queues. */
 	err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues,
vqs,
 					      io_callbacks,
-					      (const char **)io_names);
+					      (const char **)io_names, NULL);
 	if (err)
 		goto free;
 
diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c
b/drivers/gpu/drm/virtio/virtgpu_kms.c
index 036b0fb..d62ad53 100644
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -172,7 +172,7 @@ int virtio_gpu_driver_load(struct drm_device *dev, unsigned
long flags)
 		 vgdev->has_virgl_3d ? "enabled" : "not available");
 
 	ret = vgdev->vdev->config->find_vqs(vgdev->vdev, 2, vqs,
-					    callbacks, names);
+					    callbacks, names, NULL);
 	if (ret) {
 		DRM_ERROR("failed to find virt queues\n");
 		goto err_vqs;
diff --git a/drivers/misc/mic/vop/vop_main.c b/drivers/misc/mic/vop/vop_main.c
index 1a2b67f3..c2e29d7 100644
--- a/drivers/misc/mic/vop/vop_main.c
+++ b/drivers/misc/mic/vop/vop_main.c
@@ -374,7 +374,7 @@ static struct virtqueue *vop_find_vq(struct virtio_device
*dev,
 static int vop_find_vqs(struct virtio_device *dev, unsigned nvqs,
 			struct virtqueue *vqs[],
 			vq_callback_t *callbacks[],
-			const char * const names[])
+			const char * const names[], struct irq_affinity *desc)
 {
 	struct _vop_vdev *vdev = to_vopvdev(dev);
 	struct vop_device *vpdev = vdev->vpdev;
diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c
index b306210..bc0eb47 100644
--- a/drivers/net/caif/caif_virtio.c
+++ b/drivers/net/caif/caif_virtio.c
@@ -679,7 +679,8 @@ static int cfv_probe(struct virtio_device *vdev)
 		goto err;
 
 	/* Get the TX virtio ring. This is a "guest side vring". */
-	err = vdev->config->find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs,
&names);
+	err = vdev->config->find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs,
&names,
+			NULL);
 	if (err)
 		goto err;
 
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index fad84f3..08c9ee5 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1601,7 +1601,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
 	}
 
 	ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs,
callbacks,
-					 names);
+					 names, NULL);
 	if (ret)
 		goto err_find;
 
diff --git a/drivers/remoteproc/remoteproc_virtio.c
b/drivers/remoteproc/remoteproc_virtio.c
index 01870a1..49c73ce 100644
--- a/drivers/remoteproc/remoteproc_virtio.c
+++ b/drivers/remoteproc/remoteproc_virtio.c
@@ -142,7 +142,8 @@ static void rproc_virtio_del_vqs(struct virtio_device *vdev)
 static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 				 struct virtqueue *vqs[],
 				 vq_callback_t *callbacks[],
-				 const char * const names[])
+				 const char * const names[],
+				 struct irq_affinity *desc)
 {
 	int i, ret;
 
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 3090b0d..5e66e08 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -869,7 +869,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
 	init_waitqueue_head(&vrp->sendq);
 
 	/* We expect two virtqueues, rx and tx (and in this order) */
-	err = vdev->config->find_vqs(vdev, 2, vqs, vq_cbs, names);
+	err = vdev->config->find_vqs(vdev, 2, vqs, vq_cbs, names, NULL);
 	if (err)
 		goto free_vrp;
 
diff --git a/drivers/s390/virtio/kvm_virtio.c b/drivers/s390/virtio/kvm_virtio.c
index 5e5c11f..2ce0b3e 100644
--- a/drivers/s390/virtio/kvm_virtio.c
+++ b/drivers/s390/virtio/kvm_virtio.c
@@ -255,7 +255,8 @@ static void kvm_del_vqs(struct virtio_device *vdev)
 static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 			struct virtqueue *vqs[],
 			vq_callback_t *callbacks[],
-			const char * const names[])
+			const char * const names[],
+			struct irq_affinity *desc)
 {
 	struct kvm_device *kdev = to_kvmdev(vdev);
 	int i;
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index 8688ad4..8b9c3a5 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -636,7 +636,8 @@ static int virtio_ccw_register_adapter_ind(struct
virtio_ccw_device *vcdev,
 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 			       struct virtqueue *vqs[],
 			       vq_callback_t *callbacks[],
-			       const char * const names[])
+			       const char * const names[],
+			       struct irq_affinity *desc)
 {
 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 	unsigned long *indicatorp = NULL;
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index ec91bd0..32a1629 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -932,7 +932,8 @@ static int virtscsi_init(struct virtio_device *vdev,
 	}
 
 	/* Discover virtqueues and write information to configuration.  */
-	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names);
+	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
+			NULL);
 	if (err)
 		goto out;
 
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 181793f..36c9c8f 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -413,7 +413,8 @@ static int init_vqs(struct virtio_balloon *vb)
 	 * optionally stat.
 	 */
 	nvqs = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ) ? 3 : 2;
-	err = vb->vdev->config->find_vqs(vb->vdev, nvqs, vqs, callbacks,
names);
+	err = vb->vdev->config->find_vqs(vb->vdev, nvqs, vqs, callbacks,
names,
+			NULL);
 	if (err)
 		return err;
 
diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c
index 350a2a5..79f1293 100644
--- a/drivers/virtio/virtio_input.c
+++ b/drivers/virtio/virtio_input.c
@@ -173,7 +173,8 @@ static int virtinput_init_vqs(struct virtio_input *vi)
 	static const char * const names[] = { "events", "status"
};
 	int err;
 
-	err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names);
+	err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names,
+			NULL);
 	if (err)
 		return err;
 	vi->evt = vqs[0];
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 48bfea9..64c87be 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -445,7 +445,8 @@ static struct virtqueue *vm_setup_vq(struct virtio_device
*vdev, unsigned index,
 static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		       struct virtqueue *vqs[],
 		       vq_callback_t *callbacks[],
-		       const char * const names[])
+		       const char * const names[],
+		       struct irq_affinity *desc)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
 	unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index 90d7975..df7164e 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -107,20 +107,25 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
 	return vp_vring_interrupt(irq, opaque);
 }
 
-static int vp_setup_msix_vectors(struct virtio_device *vdev, int nvectors)
+static int vp_setup_msix_vectors(struct virtio_device *vdev, int nvectors,
+		struct irq_affinity *desc)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	const char *name = dev_name(&vp_dev->vdev.dev);
-	unsigned i;
+	unsigned flags = PCI_IRQ_MSIX, i;
 	int err = -ENOMEM;
 
+	if (desc) {
+		flags |= PCI_IRQ_AFFINITY;
+		desc->pre_vectors++; /* virtio config vector */
+	}
+
 	/* Try one vector per queue first. */
-	err = pci_alloc_irq_vectors(vp_dev->pci_dev, nvectors, nvectors,
-			PCI_IRQ_MSIX);
+	err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors,
+			nvectors, flags, desc);
 	if (err < 0) {
 		/* Fallback to one vector for config, one shared for queues. */
-		err = pci_alloc_irq_vectors(vp_dev->pci_dev, 2, 2,
-				PCI_IRQ_MSIX);
+		err = pci_alloc_irq_vectors(vp_dev->pci_dev, 2, 2, flags);
 		if (err < 0)
 			goto error;
 		nvectors = 2;
@@ -247,9 +252,8 @@ void vp_del_vqs(struct virtio_device *vdev)
 }
 
 static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
-			      struct virtqueue *vqs[],
-			      vq_callback_t *callbacks[],
-			      const char * const names[])
+		struct virtqueue *vqs[], vq_callback_t *callbacks[],
+		const char * const names[], struct irq_affinity *desc)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	u16 msix_vec;
@@ -265,7 +269,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev,
unsigned nvqs,
 			nvectors++;
 	}
 
-	err = vp_setup_msix_vectors(vdev, nvectors);
+	err = vp_setup_msix_vectors(vdev, nvectors, desc);
 	if (err < 0)
 		goto error_find;
 	nvectors = err;
@@ -353,13 +357,12 @@ static int vp_find_vqs_intx(struct virtio_device *vdev,
unsigned nvqs,
 
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
-		struct virtqueue *vqs[],
-		vq_callback_t *callbacks[],
-		const char * const names[])
+		struct virtqueue *vqs[], vq_callback_t *callbacks[],
+		const char * const names[], struct irq_affinity *desc)
 {
 	int err;
 
-	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names);
+	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, desc);
 	if (!err)
 		return 0;
 	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names);
diff --git a/drivers/virtio/virtio_pci_common.h
b/drivers/virtio/virtio_pci_common.h
index d041cce..85010f0 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -114,9 +114,8 @@ bool vp_notify(struct virtqueue *vq);
 void vp_del_vqs(struct virtio_device *vdev);
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
-		       struct virtqueue *vqs[],
-		       vq_callback_t *callbacks[],
-		       const char * const names[]);
+		struct virtqueue *vqs[], vq_callback_t *callbacks[],
+		const char * const names[], struct irq_affinity *desc);
 const char *vp_bus_name(struct virtio_device *vdev);
 
 /* Setup the affinity for a virtqueue:
diff --git a/drivers/virtio/virtio_pci_modern.c
b/drivers/virtio/virtio_pci_modern.c
index e18d0b0..975197b 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -387,13 +387,12 @@ static struct virtqueue *setup_vq(struct virtio_pci_device
*vp_dev,
 }
 
 static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
-			      struct virtqueue *vqs[],
-			      vq_callback_t *callbacks[],
-			      const char * const names[])
+		struct virtqueue *vqs[], vq_callback_t *callbacks[],
+		const char * const names[], struct irq_affinity *desc)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	struct virtqueue *vq;
-	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names);
+	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, desc);
 
 	if (rc)
 		return rc;
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 26c155b..2ebe506 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -7,6 +7,8 @@
 #include <linux/virtio_byteorder.h>
 #include <uapi/linux/virtio_config.h>
 
+struct irq_affinity;
+
 /**
  * virtio_config_ops - operations for configuring a virtio device
  * @get: read the value of a configuration field
@@ -68,9 +70,8 @@ struct virtio_config_ops {
 	void (*set_status)(struct virtio_device *vdev, u8 status);
 	void (*reset)(struct virtio_device *vdev);
 	int (*find_vqs)(struct virtio_device *, unsigned nvqs,
-			struct virtqueue *vqs[],
-			vq_callback_t *callbacks[],
-			const char * const names[]);
+			struct virtqueue *vqs[], vq_callback_t *callbacks[],
+			const char * const names[], struct irq_affinity *desc);
 	void (*del_vqs)(struct virtio_device *);
 	u64 (*get_features)(struct virtio_device *vdev);
 	int (*finalize_features)(struct virtio_device *vdev);
@@ -169,7 +170,7 @@ struct virtqueue *virtio_find_single_vq(struct virtio_device
*vdev,
 	vq_callback_t *callbacks[] = { c };
 	const char *names[] = { n };
 	struct virtqueue *vq;
-	int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names);
+	int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names,
NULL);
 	if (err < 0)
 		return ERR_PTR(err);
 	return vq;
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 936d7ee..09906db 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -489,7 +489,8 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
 	vsock->vdev = vdev;
 
 	ret = vsock->vdev->config->find_vqs(vsock->vdev, VSOCK_VQ_MAX,
-					    vsock->vqs, callbacks, names);
+					    vsock->vqs, callbacks, names,
+					    NULL);
 	if (ret < 0)
 		goto out;
 
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 09/11] virtio: provide a method to get the IRQ affinity mask for a virtqueue

This basically passed up the pci_irq_get_affinity information through
virtio through an optional get_vq_affinity method.  It is only implemented
by the PCI backend for now, and only when we use per-virtqueue IRQs.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/virtio/virtio_pci_common.c | 10 ++++++++++
 drivers/virtio/virtio_pci_common.h |  2 ++
 drivers/virtio/virtio_pci_legacy.c |  1 +
 drivers/virtio/virtio_pci_modern.c |  2 ++
 include/linux/virtio_config.h      |  3 +++
 5 files changed, 18 insertions(+)

diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index df7164e..25622da 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -405,6 +405,16 @@ int vp_set_vq_affinity(struct virtqueue *vq, int cpu)
 	return 0;
 }
 
+const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index)
+{
+	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+	int vec = vp_dev->vqs[index]->msix_vector;
+
+	if (vec == VIRTIO_MSI_NO_VECTOR)
+		return NULL;
+	return pci_irq_get_affinity(vp_dev->pci_dev, vec);
+}
+
 #ifdef CONFIG_PM_SLEEP
 static int virtio_pci_freeze(struct device *dev)
 {
diff --git a/drivers/virtio/virtio_pci_common.h
b/drivers/virtio/virtio_pci_common.h
index 85010f0..d6c29c5 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -125,6 +125,8 @@ const char *vp_bus_name(struct virtio_device *vdev);
  */
 int vp_set_vq_affinity(struct virtqueue *vq, int cpu);
 
+const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int
index);
+
 #if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)
 int virtio_pci_legacy_probe(struct virtio_pci_device *);
 void virtio_pci_legacy_remove(struct virtio_pci_device *);
diff --git a/drivers/virtio/virtio_pci_legacy.c
b/drivers/virtio/virtio_pci_legacy.c
index f83829f..4930b23 100644
--- a/drivers/virtio/virtio_pci_legacy.c
+++ b/drivers/virtio/virtio_pci_legacy.c
@@ -194,6 +194,7 @@ static const struct virtio_config_ops virtio_pci_config_ops
= {
 	.finalize_features = vp_finalize_features,
 	.bus_name	= vp_bus_name,
 	.set_vq_affinity = vp_set_vq_affinity,
+	.get_vq_affinity = vp_get_vq_affinity,
 };
 
 /* the PCI probing function */
diff --git a/drivers/virtio/virtio_pci_modern.c
b/drivers/virtio/virtio_pci_modern.c
index 975197b..cd09d78 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -441,6 +441,7 @@ static const struct virtio_config_ops
virtio_pci_config_nodev_ops = {
 	.finalize_features = vp_finalize_features,
 	.bus_name	= vp_bus_name,
 	.set_vq_affinity = vp_set_vq_affinity,
+	.get_vq_affinity = vp_get_vq_affinity,
 };
 
 static const struct virtio_config_ops virtio_pci_config_ops = {
@@ -456,6 +457,7 @@ static const struct virtio_config_ops virtio_pci_config_ops
= {
 	.finalize_features = vp_finalize_features,
 	.bus_name	= vp_bus_name,
 	.set_vq_affinity = vp_set_vq_affinity,
+	.get_vq_affinity = vp_get_vq_affinity,
 };
 
 /**
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 2ebe506..8355bab 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -58,6 +58,7 @@ struct irq_affinity;
  *      This returns a pointer to the bus name a la pci_name from which
  *      the caller can then copy.
  * @set_vq_affinity: set the affinity for a virtqueue.
+ * @get_vq_affinity: get the affinity for a virtqueue (optional).
  */
 typedef void vq_callback_t(struct virtqueue *);
 struct virtio_config_ops {
@@ -77,6 +78,8 @@ struct virtio_config_ops {
 	int (*finalize_features)(struct virtio_device *vdev);
 	const char *(*bus_name)(struct virtio_device *vdev);
 	int (*set_vq_affinity)(struct virtqueue *vq, int cpu);
+	const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev,
+			int index);
 };
 
 /* If driver didn't advertise the feature, it will never appear. */
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 10/11] blk-mq: provide a default queue mapping for virtio device

Similar to the PCI version, just calling into virtio instead.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 block/Kconfig                 |  5 ++++
 block/Makefile                |  1 +
 block/blk-mq-virtio.c         | 55 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/blk-mq-virtio.h | 10 ++++++++
 4 files changed, 71 insertions(+)
 create mode 100644 block/blk-mq-virtio.c
 create mode 100644 include/linux/blk-mq-virtio.h

diff --git a/block/Kconfig b/block/Kconfig
index 1d4d624..2f69b45 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -130,4 +130,9 @@ config BLK_MQ_PCI
 	depends on BLOCK && PCI
 	default y
 
+config BLK_MQ_VIRTIO
+	bool
+	depends on BLOCK && VIRTIO
+	default y
+
 source block/Kconfig.iosched
diff --git a/block/Makefile b/block/Makefile
index 36acdd75..3530a58 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -23,3 +23,4 @@ obj-$(CONFIG_BLOCK_COMPAT)	+= compat_ioctl.o
 obj-$(CONFIG_BLK_CMDLINE_PARSER)	+= cmdline-parser.o
 obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o blk-integrity.o t10-pi.o
 obj-$(CONFIG_BLK_MQ_PCI)	+= blk-mq-pci.o
+obj-$(CONFIG_BLK_MQ_VIRTIO)	+= blk-mq-virtio.o
diff --git a/block/blk-mq-virtio.c b/block/blk-mq-virtio.c
new file mode 100644
index 0000000..44d3f0d
--- /dev/null
+++ b/block/blk-mq-virtio.c
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2016 Christoph Hellwig.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+#include <linux/device.h>
+#include <linux/blk-mq.h>
+#include <linux/blk-mq-virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/module.h>
+#include "blk-mq.h"
+
+/**
+ * blk_mq_virtio_map_queues - provide a default queue mapping for virtio device
+ * @set:	tagset to provide the mapping for
+ * @vdev:	virtio device associated with @set.
+ * @first_vec:	first interrupt vectors to use for queues (usually 0)
+ *
+ * This function assumes the virtio device @vdev has at least as many available
+ * interrupt vetors as @set has queues.  It will then queuery the vector
+ * corresponding to each queue for it's affinity mask and built queue
mapping
+ * that maps a queue to the CPUs that have irq affinity for the corresponding
+ * vector.
+ */
+int blk_mq_virtio_map_queues(struct blk_mq_tag_set *set,
+		struct virtio_device *vdev, int first_vec)
+{
+	const struct cpumask *mask;
+	unsigned int queue, cpu;
+
+	if (!vdev->config->get_vq_affinity)
+		goto fallback;
+
+	/* the very first virtqueue is used internally by virtio, skip it */
+	for (queue = 0; queue < set->nr_hw_queues; queue++) {
+		mask = vdev->config->get_vq_affinity(vdev, first_vec + queue);
+		if (!mask)
+			goto fallback;
+
+		for_each_cpu(cpu, mask)
+			set->mq_map[cpu] = queue;
+	}
+
+	return 0;
+fallback:
+	return blk_mq_map_queues(set);
+}
+EXPORT_SYMBOL_GPL(blk_mq_virtio_map_queues);
diff --git a/include/linux/blk-mq-virtio.h b/include/linux/blk-mq-virtio.h
new file mode 100644
index 0000000..b1ef6e1
--- /dev/null
+++ b/include/linux/blk-mq-virtio.h
@@ -0,0 +1,10 @@
+#ifndef _LINUX_BLK_MQ_VIRTIO_H
+#define _LINUX_BLK_MQ_VIRTIO_H
+
+struct blk_mq_tag_set;
+struct virtio_device;
+
+int blk_mq_virtio_map_queues(struct blk_mq_tag_set *set,
+		struct virtio_device *vdev, int first_vec);
+
+#endif /* _LINUX_BLK_MQ_VIRTIO_H */
-- 
2.1.4

Christoph Hellwig

2016-Nov-17 10:43 UTC

head link

[PATCH 11/11] virtio_blk: use virtio IRQ affinity

Use automatic IRQ affinity assignment in the virtio layer if available,
and build the blk-mq queues based on it.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/block/virtio_blk.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 689e790..7982090 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -5,6 +5,7 @@
 #include <linux/hdreg.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/interrupt.h>
 #include <linux/virtio.h>
 #include <linux/virtio_blk.h>
 #include <linux/scatterlist.h>
@@ -12,6 +13,7 @@
 #include <scsi/scsi_cmnd.h>
 #include <linux/idr.h>
 #include <linux/blk-mq.h>
+#include <linux/blk-mq-virtio.h>
 #include <linux/numa.h>
 
 #define PART_BITS 4
@@ -383,6 +385,7 @@ static int init_vq(struct virtio_blk *vblk)
 	struct virtqueue **vqs;
 	unsigned short num_vqs;
 	struct virtio_device *vdev = vblk->vdev;
+	struct irq_affinity desc = { 0, };
 
 	err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ,
 				   struct virtio_blk_config, num_queues,
@@ -410,7 +413,7 @@ static int init_vq(struct virtio_blk *vblk)
 
 	/* Discover virtqueues and write information to configuration.  */
 	err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
-			NULL);
+			&desc);
 	if (err)
 		goto out;
 
@@ -541,10 +544,18 @@ static int virtblk_init_request(void *data, struct request
*rq,
 	return 0;
 }
 
+static int virtblk_map_queues(struct blk_mq_tag_set *set)
+{
+	struct virtio_blk *vblk = set->driver_data;
+
+	return blk_mq_virtio_map_queues(set, vblk->vdev, 0);
+}
+
 static struct blk_mq_ops virtio_mq_ops = {
 	.queue_rq	= virtio_queue_rq,
 	.complete	= virtblk_request_done,
 	.init_request	= virtblk_init_request,
+	.map_queues	= virtblk_map_queues,
 };
 
 static unsigned int virtblk_queue_depth;
-- 
2.1.4

Christoph Hellwig

2016-Nov-25 07:25 UTC

head link

automatic IRQ affinity for virtio

Btw, what's the best way to get any response to this series?
But this and the predecessor seem to have completly fallen on deaf
ears.

Michael S. Tsirkin

2016-Nov-27 03:37 UTC

head link

automatic IRQ affinity for virtio

On Fri, Nov 25, 2016 at 08:25:38AM +0100, Christoph Hellwig
wrote:> Btw, what's the best way to get any response to this series?
> But this and the predecessor seem to have completly fallen on deaf
> ears.
I'm sorry, I intend to review soon and if OK merge it.

The fact that it depends on tip means I can't put
it in my first pull request (until tip is merged)
so I deferred review somewhat.

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[PATCH 01/11] virtio_pci: use pci_alloc_irq_vectors

[PATCH 02/11] virtio_pci: remove the call to vp_free_vectors in vp_request_msix_vectors

[PATCH 03/11] virtio_pci: merge vp_free_vectors into vp_del_vqs

[PATCH 04/11] virtio_pci: split vp_try_to_find_vqs into INTx and MSI-X variants

[PATCH 05/11] virtio_pci: use shared interrupts for virtqueues

[PATCH 06/11] virtio_pci: use msix_enable flag in struct pci_dev

[PATCH 07/11] virtio_pci: simplify MSI-X setup

[PATCH 08/11] virtio: allow drivers to request IRQ affinity when creating VQs

[PATCH 09/11] virtio: provide a method to get the IRQ affinity mask for a virtqueue

[PATCH 10/11] blk-mq: provide a default queue mapping for virtio device

[PATCH 11/11] virtio_blk: use virtio IRQ affinity

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