If we want a virtio device to work in vDPA (vhost data path acceleration)
mode, we could add a "vdpa=1" devarg for this device to specify the mode.
This patch let virtio pmd skip device probe when detecting this parameter.
Signed-off-by: Xiao Wang <xiao.w.w...@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coque...@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yi...@intel.com>
---
doc/guides/nics/virtio.rst | 13 ++++++++++++
drivers/net/virtio/virtio_ethdev.c | 43 ++++++++++++++++++++++++++++++++++++++
2 files changed, 56 insertions(+)
diff --git a/doc/guides/nics/virtio.rst b/doc/guides/nics/virtio.rst
index ca09cd203..8922f9c0b 100644
--- a/doc/guides/nics/virtio.rst
+++ b/doc/guides/nics/virtio.rst
@@ -318,3 +318,16 @@ Here we use l3fwd-power as an example to show how to get
started.
$ l3fwd-power -l 0-1 -- -p 1 -P --config="(0,0,1)" \
--no-numa --parse-ptype
+
+
+Virtio PMD arguments
+--------------------
+
+The user can specify below argument in devargs.
+
+#. ``vdpa``:
+
+ A virtio device could also be driven by vDPA (vhost data path acceleration)
+ driver, and works as a HW vhost backend. This argument is used to specify
+ a virtio device needs to work in vDPA mode.
+ (Default: 0 (disabled))
diff --git a/drivers/net/virtio/virtio_ethdev.c
b/drivers/net/virtio/virtio_ethdev.c
index 11f758929..6d6c50e89 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -28,6 +28,7 @@
#include <rte_eal.h>
#include <rte_dev.h>
#include <rte_cycles.h>
+#include <rte_kvargs.h>
#include "virtio_ethdev.h"
#include "virtio_pci.h"
@@ -1708,9 +1709,51 @@ eth_virtio_dev_uninit(struct rte_eth_dev *eth_dev)
return 0;
}
+static int vdpa_check_handler(__rte_unused const char *key,
+ const char *value, __rte_unused void *opaque)
+{
+ if (strcmp(value, "1"))
+ return -1;
+
+ return 0;
+}
+
+static int
+vdpa_mode_selected(struct rte_devargs *devargs)
+{
+ struct rte_kvargs *kvlist;
+ const char *key = "vdpa";
+ int ret = 0;
+
+ if (devargs == NULL)
+ return 0;
+
+ kvlist = rte_kvargs_parse(devargs->args, NULL);
+ if (kvlist == NULL)
+ return 0;
+
+ if (!rte_kvargs_count(kvlist, key))
+ goto exit;
+
+ /* vdpa mode selected when there's a key-value pair: vdpa=1 */
+ if (rte_kvargs_process(kvlist, key,
+ vdpa_check_handler, NULL) < 0) {
+ goto exit;
+ }
+ ret = 1;
+
+exit:
+ rte_kvargs_free(kvlist);
+ return ret;
+}
+
static int eth_virtio_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
struct rte_pci_device *pci_dev)
{
+ /* virtio pmd skips probe if device needs to work in vdpa mode */
+ if (vdpa_mode_selected(pci_dev->device.devargs))
+ return 1;
+
return rte_eth_dev_pci_generic_probe(pci_dev, sizeof(struct virtio_hw),
eth_virtio_dev_init);
}
--
2.15.1
