[dpdk-dev] [PATCH v3 02/21] net/virtio: vring init for packed queues
Jens Freimann
jfreimann at redhat.com
Thu Apr 5 16:24:18 CEST 2018
On Thu, Apr 05, 2018 at 04:15:56PM +0200, Maxime Coquelin wrote:
>
>
>On 04/05/2018 12:10 PM, Jens Freimann wrote:
>>Add and initialize descriptor data structures.
>>
>>Signed-off-by: Jens Freimann <jfreimann at redhat.com>
>>---
>> drivers/net/virtio/virtio_ethdev.c | 22 +++++++++-------
>> drivers/net/virtio/virtio_pci.h | 8 ++++++
>> drivers/net/virtio/virtio_ring.h | 53 ++++++++++++++++++++++++++++++++++----
>> drivers/net/virtio/virtqueue.h | 10 +++++++
>> 4 files changed, 78 insertions(+), 15 deletions(-)
>>
>>diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
>>index 06fbf7311..cccefafe9 100644
>>--- a/drivers/net/virtio/virtio_ethdev.c
>>+++ b/drivers/net/virtio/virtio_ethdev.c
>>@@ -298,19 +298,21 @@ virtio_init_vring(struct virtqueue *vq)
>> PMD_INIT_FUNC_TRACE();
>>- /*
>>- * Reinitialise since virtio port might have been stopped and restarted
>>- */
>> memset(ring_mem, 0, vq->vq_ring_size);
>>- vring_init(vr, size, ring_mem, VIRTIO_PCI_VRING_ALIGN);
>>- vq->vq_used_cons_idx = 0;
>>- vq->vq_desc_head_idx = 0;
>>- vq->vq_avail_idx = 0;
>>- vq->vq_desc_tail_idx = (uint16_t)(vq->vq_nentries - 1);
>>+ vring_init(vq->hw, vr, size, ring_mem, VIRTIO_PCI_VRING_ALIGN);
>>+
>> vq->vq_free_cnt = vq->vq_nentries;
>> memset(vq->vq_descx, 0, sizeof(struct vq_desc_extra) * vq->vq_nentries);
>>+ vq->vq_used_cons_idx = 0;
>>+ vq->vq_avail_idx = 0;
>>+ if (vtpci_packed_queue(vq->hw)) {
>>+ vring_desc_init_packed(vr, size);
>>+ } else {
>>+ vq->vq_desc_head_idx = 0;
>>+ vq->vq_desc_tail_idx = (uint16_t)(vq->vq_nentries - 1);
>>- vring_desc_init(vr->desc, size);
>>+ vring_desc_init(vr->desc, size);
>>+ }
>> /*
>> * Disable device(host) interrupting guest
>>@@ -385,7 +387,7 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t vtpci_queue_idx)
>> /*
>> * Reserve a memzone for vring elements
>> */
>>- size = vring_size(vq_size, VIRTIO_PCI_VRING_ALIGN);
>>+ size = vring_size(hw, vq_size, VIRTIO_PCI_VRING_ALIGN);
>> vq->vq_ring_size = RTE_ALIGN_CEIL(size, VIRTIO_PCI_VRING_ALIGN);
>> PMD_INIT_LOG(DEBUG, "vring_size: %d, rounded_vring_size: %d",
>> size, vq->vq_ring_size);
>>diff --git a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
>>index a28ba8339..528fb46b9 100644
>>--- a/drivers/net/virtio/virtio_pci.h
>>+++ b/drivers/net/virtio/virtio_pci.h
>>@@ -112,6 +112,8 @@ struct virtnet_ctl;
>> #define VIRTIO_F_VERSION_1 32
>> #define VIRTIO_F_IOMMU_PLATFORM 33
>>+#define VIRTIO_F_RING_PACKED 34
>>+#define VIRTIO_F_IN_ORDER 35
>> /*
>> * Some VirtIO feature bits (currently bits 28 through 31) are
>>@@ -304,6 +306,12 @@ vtpci_with_feature(struct virtio_hw *hw, uint64_t bit)
>> return (hw->guest_features & (1ULL << bit)) != 0;
>> }
>>+static inline int
>>+vtpci_packed_queue(struct virtio_hw *hw)
>>+{
>>+ return vtpci_with_feature(hw, VIRTIO_F_RING_PACKED);
>>+}
>>+
>> /*
>> * Function declaration from virtio_pci.c
>> */
>>diff --git a/drivers/net/virtio/virtio_ring.h b/drivers/net/virtio/virtio_ring.h
>>index 9e3c2a015..1bd7ba98e 100644
>>--- a/drivers/net/virtio/virtio_ring.h
>>+++ b/drivers/net/virtio/virtio_ring.h
>>@@ -9,6 +9,7 @@
>> #include <rte_common.h>
>>+
>Remove new line
>
>> /* This marks a buffer as continuing via the next field. */
>> #define VRING_DESC_F_NEXT 1
>> /* This marks a buffer as write-only (otherwise read-only). */
>>@@ -54,11 +55,38 @@ struct vring_used {
>> struct vring_used_elem ring[0];
>> };
>>+/* For support of packed virtqueues in Virtio 1.1 the format of descriptors
>>+ * looks like this.
>>+ */
>>+struct vring_desc_packed {
>>+ uint64_t addr;
>>+ uint32_t len;
>>+ uint16_t index;
>>+ uint16_t flags;
>>+};
>>+
>>+#define RING_EVENT_FLAGS_ENABLE 0x0
>>+#define RING_EVENT_FLAGS_DISABLE 0x1
>>+#define RING_EVENT_FLAGS_DESC 0x2
>>+struct vring_packed_desc_event {
>>+ uint16_t desc_event_off_wrap;
>>+ uint16_t desc_event_flags;
>>+};
>>+
>> struct vring {
>> unsigned int num;
>>- struct vring_desc *desc;
>>- struct vring_avail *avail;
>>- struct vring_used *used;
>>+ union {
>>+ struct vring_desc_packed *desc_packed;
>>+ struct vring_desc *desc;
>>+ };
>>+ union {
>>+ struct vring_avail *avail;
>>+ struct vring_packed_desc_event *driver_event;
>>+ };
>>+ union {
>>+ struct vring_used *used;
>>+ struct vring_packed_desc_event *device_event;
>>+ };
>
>Not a must, but I wonder if it wouldn't be cleaner to have a unique
>union of two structs, one for packed rings, and one for the legacy.
>I may be wrong, though.
I'm not sure either but this looked best to me.
Thanks!
regards,
Jens
>
>> };
>> /* The standard layout for the ring is a continuous chunk of memory which
>>@@ -95,10 +123,16 @@ struct vring {
>> #define vring_avail_event(vr) (*(uint16_t *)&(vr)->used->ring[(vr)->num])
>> static inline size_t
>>-vring_size(unsigned int num, unsigned long align)
>>+vring_size(struct virtio_hw *hw, unsigned int num, unsigned long align)
>> {
>> size_t size;
>>+ if (vtpci_packed_queue(hw)) {
>>+ size = num * sizeof(struct vring_desc_packed);
>>+ size += 2 * sizeof(struct vring_packed_desc_event);
>>+ return size;
>>+ }
>>+
>> size = num * sizeof(struct vring_desc);
>> size += sizeof(struct vring_avail) + (num * sizeof(uint16_t));
>> size = RTE_ALIGN_CEIL(size, align);
>>@@ -108,10 +142,19 @@ vring_size(unsigned int num, unsigned long align)
>> }
>> static inline void
>>-vring_init(struct vring *vr, unsigned int num, uint8_t *p,
>>+vring_init(struct virtio_hw *hw, struct vring *vr, unsigned int num, uint8_t *p,
>> unsigned long align)
>> {
>> vr->num = num;
>>+ if (vtpci_packed_queue(hw)) {
>>+ vr->desc_packed = (struct vring_desc_packed *)p;
>>+ vr->driver_event = (struct vring_packed_desc_event *) (p +
>>+ num * sizeof(struct vring_desc_packed));
>>+ vr->device_event = (struct vring_packed_desc_event *) (vr->driver_event +
>>+ sizeof(struct vring_packed_desc_event));
>>+ return;
>>+ }
>>+
>> vr->desc = (struct vring_desc *) p;
>> vr->avail = (struct vring_avail *) (p +
>> num * sizeof(struct vring_desc));
>>diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
>>index 14364f356..cc2e7c0f6 100644
>>--- a/drivers/net/virtio/virtqueue.h
>>+++ b/drivers/net/virtio/virtqueue.h
>>@@ -245,6 +245,16 @@ struct virtio_tx_region {
>> __attribute__((__aligned__(16)));
>> };
>>+static inline void
>>+vring_desc_init_packed(struct vring *vr, int n)
>>+{
>>+ int i;
>>+ for (i = 0; i < n; i++) {
>>+ struct vring_desc_packed *desc = &vr->desc_packed[i];
>>+ desc->index = i;
>>+ }
>>+}
>>+
>> /* Chain all the descriptors in the ring with an END */
>> static inline void
>> vring_desc_init(struct vring_desc *dp, uint16_t n)
>>
More information about the dev
mailing list