This patch extends the XDP Tx metadata framework to include Earliest
TxTime First (ETF) HW offload support where the NIC will schedule the
packet for transmission at a pre-determined time called txtime. The value
of txtime is communicated from user space to Ethernet driver via txtime
field of struct xsk_tx_metadata.
Suggested-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
Signed-off-by: Song Yoong Siang <yoong.siang.song@xxxxxxxxx>
---
Documentation/netlink/specs/netdev.yaml | 4 ++++
Documentation/networking/xsk-tx-metadata.rst | 5 +++++
include/net/xdp_sock.h | 9 +++++++++
include/net/xdp_sock_drv.h | 1 +
include/uapi/linux/if_xdp.h | 9 +++++++++
include/uapi/linux/netdev.h | 3 +++
net/core/netdev-genl.c | 2 ++
net/xdp/xsk.c | 3 +++
tools/include/uapi/linux/if_xdp.h | 9 +++++++++
tools/include/uapi/linux/netdev.h | 3 +++
tools/net/ynl/generated/netdev-user.c | 1 +
11 files changed, 49 insertions(+)
diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index 00439bcbd2e3..339cdcddbfc0 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -66,6 +66,10 @@ definitions:
name: tx-checksum
doc:
L3 checksum HW offload is supported by the driver.
+ -
+ name: txtime
+ doc:
+ Earliest TxTime First (ETF) HW offload is supported by the driver.
attribute-sets:
-
diff --git a/Documentation/networking/xsk-tx-metadata.rst b/Documentation/networking/xsk-tx-metadata.rst
index 97ecfa480d00..654ff692062a 100644
--- a/Documentation/networking/xsk-tx-metadata.rst
+++ b/Documentation/networking/xsk-tx-metadata.rst
@@ -44,6 +44,10 @@ The flags field enables the particular offload:
checksum. ``csum_start`` specifies byte offset of where the checksumming
should start and ``csum_offset`` specifies byte offset where the
device should store the computed checksum.
+- ``XDP_TXMD_FLAGS_TXTIME``: requests Earliest TxTime First (ETF) HW
+ offload to launch the packet at a pre-determined time. ``txtime``
+ indicates the time which the NIC should schedule the packet for
+ transmission.
Besides the flags above, in order to trigger the offloads, the first
packet's ``struct xdp_desc`` descriptor should set ``XDP_TX_METADATA``
@@ -68,6 +72,7 @@ Refer to ``xsk-flags`` features bitmask in
- ``tx-timestamp``: device supports ``XDP_TXMD_FLAGS_TIMESTAMP``
- ``tx-checksum``: device supports ``XDP_TXMD_FLAGS_CHECKSUM``
+- ``txtime``: device supports ``XDP_TXMD_FLAGS_TXTIME``
See ``tools/net/ynl/samples/netdev.c`` on how to query this information.
diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
index 3cb4dc9bd70e..0651b5264b72 100644
--- a/include/net/xdp_sock.h
+++ b/include/net/xdp_sock.h
@@ -110,11 +110,16 @@ struct xdp_sock {
* indicates position where checksumming should start.
* csum_offset indicates position where checksum should be stored.
*
+ * void (*tmo_request_txtime)(u64 txtime, void *priv)
+ * Called when AF_XDP frame requested Earliest TxTime First (ETF) HW offload
+ * support. txtime indicates the time which the NIC should schedule the
+ * packet for transmission.
*/
struct xsk_tx_metadata_ops {
void (*tmo_request_timestamp)(void *priv);
u64 (*tmo_fill_timestamp)(void *priv);
void (*tmo_request_checksum)(u16 csum_start, u16 csum_offset, void *priv);
+ void (*tmo_request_txtime)(u64 txtime, void *priv);
};
#ifdef CONFIG_XDP_SOCKETS
@@ -170,6 +175,10 @@ static inline void xsk_tx_metadata_request(const struct xsk_tx_metadata *meta,
if (meta->flags & XDP_TXMD_FLAGS_CHECKSUM)
ops->tmo_request_checksum(meta->request.csum_start,
meta->request.csum_offset, priv);
+
+ if (ops->tmo_request_txtime)
+ if (meta->flags & XDP_TXMD_FLAGS_TXTIME)
+ ops->tmo_request_txtime(meta->request.txtime, priv);
}
/**
diff --git a/include/net/xdp_sock_drv.h b/include/net/xdp_sock_drv.h
index 81e02de3f453..e66d597e7079 100644
--- a/include/net/xdp_sock_drv.h
+++ b/include/net/xdp_sock_drv.h
@@ -168,6 +168,7 @@ static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
#define XDP_TXMD_FLAGS_VALID ( \
XDP_TXMD_FLAGS_TIMESTAMP | \
XDP_TXMD_FLAGS_CHECKSUM | \
+ XDP_TXMD_FLAGS_TXTIME | \
0)
static inline bool xsk_buff_valid_tx_metadata(struct xsk_tx_metadata *meta)
diff --git a/include/uapi/linux/if_xdp.h b/include/uapi/linux/if_xdp.h
index d31698410410..24d123bce7f3 100644
--- a/include/uapi/linux/if_xdp.h
+++ b/include/uapi/linux/if_xdp.h
@@ -123,6 +123,12 @@ struct xdp_options {
*/
#define XDP_TXMD_FLAGS_CHECKSUM (1 << 1)
+/* Request Earliest TxTime First (ETF) HW offload to launch the packet at a
+ * pre-determined time. The time which the NIC should schedule the packet for
+ * transmission is communicated via txtime field of struct xsk_tx_metadata.
+ */
+#define XDP_TXMD_FLAGS_TXTIME (1 << 2)
+
/* AF_XDP offloads request. 'request' union member is consumed by the driver
* when the packet is being transmitted. 'completion' union member is
* filled by the driver when the transmit completion arrives.
@@ -138,6 +144,9 @@ struct xsk_tx_metadata {
__u16 csum_start;
/* Offset from csum_start where checksum should be stored. */
__u16 csum_offset;
+
+ /* XDP_TXMD_FLAGS_TXTIME */
+ __u64 txtime;
} request;
struct {
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index 48d5477a668c..03b913757e1c 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -59,10 +59,13 @@ enum netdev_xdp_rx_metadata {
* by the driver.
* @NETDEV_XSK_FLAGS_TX_CHECKSUM: L3 checksum HW offload is supported by the
* driver.
+ * @NETDEV_XSK_FLAGS_TXTIME: Earliest TxTime First (ETF) HW offload is supported
+ * by the driver.
*/
enum netdev_xsk_flags {
NETDEV_XSK_FLAGS_TX_TIMESTAMP = 1,
NETDEV_XSK_FLAGS_TX_CHECKSUM = 2,
+ NETDEV_XSK_FLAGS_TXTIME = 3,
/* private: */
NETDEV_XSK_FLAGS_MASK = 3,
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 10f2124e9e23..aecc6e26f839 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -33,6 +33,8 @@ XDP_METADATA_KFUNC_xxx
xsk_features |= NETDEV_XSK_FLAGS_TX_TIMESTAMP;
if (netdev->xsk_tx_metadata_ops->tmo_request_checksum)
xsk_features |= NETDEV_XSK_FLAGS_TX_CHECKSUM;
+ if (netdev->xsk_tx_metadata_ops->tmo_request_txtime)
+ xsk_features |= NETDEV_XSK_FLAGS_TXTIME;
}
if (nla_put_u32(rsp, NETDEV_A_DEV_IFINDEX, netdev->ifindex) ||
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 281d49b4fca4..4d48fc6caf7c 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -751,6 +751,9 @@ static struct sk_buff *xsk_build_skb(struct xdp_sock *xs,
goto free_err;
}
}
+
+ if (meta->flags & XDP_TXMD_FLAGS_TXTIME)
+ skb->skb_mstamp_ns = meta->request.txtime;
}
}
diff --git a/tools/include/uapi/linux/if_xdp.h b/tools/include/uapi/linux/if_xdp.h
index 638c606dfa74..abcf79e8a879 100644
--- a/tools/include/uapi/linux/if_xdp.h
+++ b/tools/include/uapi/linux/if_xdp.h
@@ -123,6 +123,12 @@ struct xdp_options {
*/
#define XDP_TXMD_FLAGS_CHECKSUM (1 << 1)
+/* Request Earliest TxTime First (ETF) HW offload to launch the packet at a
+ * pre-determined time. The time which the NIC should schedule the packet for
+ * transmission is communicated via txtime field of struct xsk_tx_metadata.
+ */
+#define XDP_TXMD_FLAGS_TXTIME (1 << 2)
+
/* AF_XDP offloads request. 'request' union member is consumed by the driver
* when the packet is being transmitted. 'completion' union member is
* filled by the driver when the transmit completion arrives.
@@ -138,6 +144,9 @@ struct xsk_tx_metadata {
__u16 csum_start;
/* Offset from csum_start where checksum should be stored. */
__u16 csum_offset;
+
+ /* XDP_TXMD_FLAGS_TXTIME */
+ __u64 txtime;
} request;
struct {
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index 48d5477a668c..03b913757e1c 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -59,10 +59,13 @@ enum netdev_xdp_rx_metadata {
* by the driver.
* @NETDEV_XSK_FLAGS_TX_CHECKSUM: L3 checksum HW offload is supported by the
* driver.
+ * @NETDEV_XSK_FLAGS_TXTIME: Earliest TxTime First (ETF) HW offload is supported
+ * by the driver.
*/
enum netdev_xsk_flags {
NETDEV_XSK_FLAGS_TX_TIMESTAMP = 1,
NETDEV_XSK_FLAGS_TX_CHECKSUM = 2,
+ NETDEV_XSK_FLAGS_TXTIME = 3,
/* private: */
NETDEV_XSK_FLAGS_MASK = 3,
diff --git a/tools/net/ynl/generated/netdev-user.c b/tools/net/ynl/generated/netdev-user.c
index 6283d87dad37..02f1bd4cd97b 100644
--- a/tools/net/ynl/generated/netdev-user.c
+++ b/tools/net/ynl/generated/netdev-user.c
@@ -61,6 +61,7 @@ const char *netdev_xdp_rx_metadata_str(enum netdev_xdp_rx_metadata value)
static const char * const netdev_xsk_flags_strmap[] = {
[0] = "tx-timestamp",
[1] = "tx-checksum",
+ [2] = "txtime"
};
const char *netdev_xsk_flags_str(enum netdev_xsk_flags value)
--
2.34.1
