| Message ID | 20220408071245.40554-2-huangguangbin2@huawei.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: ethool: add support to get/set tx push by ethtool -G/g | expand |
On Fri, 8 Apr 2022 15:12:43 +0800 Guangbin Huang wrote: > From: Jie Wang <wangjie125@huawei.com> > > Currently tx push is a standard driver feature which controls use of a fast > path descriptor push. So this patch extends the ringparam APIs and data > structures to support set/get tx push by ethtool -G/g. > > Signed-off-by: Jie Wang <wangjie125@huawei.com> > Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com> > +``ETHTOOL_A_RINGS_TX_PUSH`` flag is used to choose the ordinary path or the fast > +path to send packets. In ordinary path, driver fills BDs to DDR memory and > +notifies NIC hardware. In fast path, driver pushes BDs to the device memory > +directly and thus reducing the sending latencies. Setting tx push attribute "on" > +will enable tx push mode and send packets in fast path if packet size matches. > +For those not supported hardwares, this attributes is "off" by default settings. Since you need to respin to fix the kdoc warning - could you also add a mention that enabling this feature may increase CPU cost? Unless it's not the case for your implementation, I thought it usually is.. > RINGS_SET > ========= > @@ -887,6 +894,7 @@ Request contents: > ``ETHTOOL_A_RINGS_TX`` u32 size of TX ring > ``ETHTOOL_A_RINGS_RX_BUF_LEN`` u32 size of buffers on the ring > ``ETHTOOL_A_RINGS_CQE_SIZE`` u32 Size of TX/RX CQE > + ``ETHTOOL_A_RINGS_TX_PUSH`` u8 flag of TX Push mode > ==================================== ====== =========================== > > Kernel checks that requested ring sizes do not exceed limits reported by > diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h > index 4af58459a1e7..ede4f9154cd2 100644 > --- a/include/linux/ethtool.h > +++ b/include/linux/ethtool.h > @@ -71,11 +71,13 @@ enum { > * struct kernel_ethtool_ringparam - RX/TX ring configuration > * @rx_buf_len: Current length of buffers on the rx ring. > * @tcp_data_split: Scatter packet headers and data to separate buffers > + * @tx_push: The flag of tx push mode > * @cqe_size: Size of TX/RX completion queue event > */ > struct kernel_ethtool_ringparam { > u32 rx_buf_len; > u8 tcp_data_split; > + u8 tx_push; > u32 cqe_size; > }; > > @@ -87,6 +89,7 @@ struct kernel_ethtool_ringparam { > enum ethtool_supported_ring_param { > ETHTOOL_RING_USE_RX_BUF_LEN = BIT(0), > ETHTOOL_RING_USE_CQE_SIZE = BIT(1), > + ETHTOOL_RING_USE_TX_PUSH = BIT(2), include/linux/ethtool.h:94: warning: Enum value 'ETHTOOL_RING_USE_TX_PUSH' not described in enum 'ethtool_supported_ring_param'
On 2022/4/9 5:55, Jakub Kicinski wrote: > On Fri, 8 Apr 2022 15:12:43 +0800 Guangbin Huang wrote: >> From: Jie Wang <wangjie125@huawei.com> >> >> Currently tx push is a standard driver feature which controls use of a fast >> path descriptor push. So this patch extends the ringparam APIs and data >> structures to support set/get tx push by ethtool -G/g. >> >> Signed-off-by: Jie Wang <wangjie125@huawei.com> >> Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com> > >> +``ETHTOOL_A_RINGS_TX_PUSH`` flag is used to choose the ordinary path or the fast >> +path to send packets. In ordinary path, driver fills BDs to DDR memory and >> +notifies NIC hardware. In fast path, driver pushes BDs to the device memory >> +directly and thus reducing the sending latencies. Setting tx push attribute "on" >> +will enable tx push mode and send packets in fast path if packet size matches. >> +For those not supported hardwares, this attributes is "off" by default settings. > > Since you need to respin to fix the kdoc warning - could you also add > a mention that enabling this feature may increase CPU cost? Unless it's > not the case for your implementation, I thought it usually is.. > ok, i will add it in v2 >> RINGS_SET >> ========= >> @@ -887,6 +894,7 @@ Request contents: >> ``ETHTOOL_A_RINGS_TX`` u32 size of TX ring >> ``ETHTOOL_A_RINGS_RX_BUF_LEN`` u32 size of buffers on the ring >> ``ETHTOOL_A_RINGS_CQE_SIZE`` u32 Size of TX/RX CQE >> + ``ETHTOOL_A_RINGS_TX_PUSH`` u8 flag of TX Push mode >> ==================================== ====== =========================== >> >> Kernel checks that requested ring sizes do not exceed limits reported by >> diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h >> index 4af58459a1e7..ede4f9154cd2 100644 >> --- a/include/linux/ethtool.h >> +++ b/include/linux/ethtool.h >> @@ -71,11 +71,13 @@ enum { >> * struct kernel_ethtool_ringparam - RX/TX ring configuration >> * @rx_buf_len: Current length of buffers on the rx ring. >> * @tcp_data_split: Scatter packet headers and data to separate buffers >> + * @tx_push: The flag of tx push mode >> * @cqe_size: Size of TX/RX completion queue event >> */ >> struct kernel_ethtool_ringparam { >> u32 rx_buf_len; >> u8 tcp_data_split; >> + u8 tx_push; >> u32 cqe_size; >> }; >> >> @@ -87,6 +89,7 @@ struct kernel_ethtool_ringparam { >> enum ethtool_supported_ring_param { >> ETHTOOL_RING_USE_RX_BUF_LEN = BIT(0), >> ETHTOOL_RING_USE_CQE_SIZE = BIT(1), >> + ETHTOOL_RING_USE_TX_PUSH = BIT(2), > > include/linux/ethtool.h:94: warning: Enum value 'ETHTOOL_RING_USE_TX_PUSH' not described in enum 'ethtool_supported_ring_param' thx, I will fix it in v2 > > > . >
diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst index 24d9be69065d..fcd4fdf96c8e 100644 --- a/Documentation/networking/ethtool-netlink.rst +++ b/Documentation/networking/ethtool-netlink.rst @@ -862,6 +862,7 @@ Kernel response contents: ``ETHTOOL_A_RINGS_RX_BUF_LEN`` u32 size of buffers on the ring ``ETHTOOL_A_RINGS_TCP_DATA_SPLIT`` u8 TCP header / data split ``ETHTOOL_A_RINGS_CQE_SIZE`` u32 Size of TX/RX CQE + ``ETHTOOL_A_RINGS_TX_PUSH`` u8 flag of TX Push mode ==================================== ====== =========================== ``ETHTOOL_A_RINGS_TCP_DATA_SPLIT`` indicates whether the device is usable with @@ -871,6 +872,12 @@ separate buffers. The device configuration must make it possible to receive full memory pages of data, for example because MTU is high enough or through HW-GRO. +``ETHTOOL_A_RINGS_TX_PUSH`` flag is used to choose the ordinary path or the fast +path to send packets. In ordinary path, driver fills BDs to DDR memory and +notifies NIC hardware. In fast path, driver pushes BDs to the device memory +directly and thus reducing the sending latencies. Setting tx push attribute "on" +will enable tx push mode and send packets in fast path if packet size matches. +For those not supported hardwares, this attributes is "off" by default settings. RINGS_SET ========= @@ -887,6 +894,7 @@ Request contents: ``ETHTOOL_A_RINGS_TX`` u32 size of TX ring ``ETHTOOL_A_RINGS_RX_BUF_LEN`` u32 size of buffers on the ring ``ETHTOOL_A_RINGS_CQE_SIZE`` u32 Size of TX/RX CQE + ``ETHTOOL_A_RINGS_TX_PUSH`` u8 flag of TX Push mode ==================================== ====== =========================== Kernel checks that requested ring sizes do not exceed limits reported by diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index 4af58459a1e7..ede4f9154cd2 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -71,11 +71,13 @@ enum { * struct kernel_ethtool_ringparam - RX/TX ring configuration * @rx_buf_len: Current length of buffers on the rx ring. * @tcp_data_split: Scatter packet headers and data to separate buffers + * @tx_push: The flag of tx push mode * @cqe_size: Size of TX/RX completion queue event */ struct kernel_ethtool_ringparam { u32 rx_buf_len; u8 tcp_data_split; + u8 tx_push; u32 cqe_size; }; @@ -87,6 +89,7 @@ struct kernel_ethtool_ringparam { enum ethtool_supported_ring_param { ETHTOOL_RING_USE_RX_BUF_LEN = BIT(0), ETHTOOL_RING_USE_CQE_SIZE = BIT(1), + ETHTOOL_RING_USE_TX_PUSH = BIT(2), }; #define __ETH_RSS_HASH_BIT(bit) ((u32)1 << (bit)) diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h index 979850221b8d..d2fb4f7be61b 100644 --- a/include/uapi/linux/ethtool_netlink.h +++ b/include/uapi/linux/ethtool_netlink.h @@ -338,6 +338,7 @@ enum { ETHTOOL_A_RINGS_RX_BUF_LEN, /* u32 */ ETHTOOL_A_RINGS_TCP_DATA_SPLIT, /* u8 */ ETHTOOL_A_RINGS_CQE_SIZE, /* u32 */ + ETHTOOL_A_RINGS_TX_PUSH, /* u8 */ /* add new constants above here */ __ETHTOOL_A_RINGS_CNT, diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h index 29d01662a48b..7919ddb2371c 100644 --- a/net/ethtool/netlink.h +++ b/net/ethtool/netlink.h @@ -363,7 +363,7 @@ extern const struct nla_policy ethnl_features_set_policy[ETHTOOL_A_FEATURES_WANT extern const struct nla_policy ethnl_privflags_get_policy[ETHTOOL_A_PRIVFLAGS_HEADER + 1]; extern const struct nla_policy ethnl_privflags_set_policy[ETHTOOL_A_PRIVFLAGS_FLAGS + 1]; extern const struct nla_policy ethnl_rings_get_policy[ETHTOOL_A_RINGS_HEADER + 1]; -extern const struct nla_policy ethnl_rings_set_policy[ETHTOOL_A_RINGS_CQE_SIZE + 1]; +extern const struct nla_policy ethnl_rings_set_policy[ETHTOOL_A_RINGS_TX_PUSH + 1]; extern const struct nla_policy ethnl_channels_get_policy[ETHTOOL_A_CHANNELS_HEADER + 1]; extern const struct nla_policy ethnl_channels_set_policy[ETHTOOL_A_CHANNELS_COMBINED_COUNT + 1]; extern const struct nla_policy ethnl_coalesce_get_policy[ETHTOOL_A_COALESCE_HEADER + 1]; diff --git a/net/ethtool/rings.c b/net/ethtool/rings.c index 9f33c9689b56..9ed60c507d97 100644 --- a/net/ethtool/rings.c +++ b/net/ethtool/rings.c @@ -55,7 +55,8 @@ static int rings_reply_size(const struct ethnl_req_info *req_base, nla_total_size(sizeof(u32)) + /* _RINGS_TX */ nla_total_size(sizeof(u32)) + /* _RINGS_RX_BUF_LEN */ nla_total_size(sizeof(u8)) + /* _RINGS_TCP_DATA_SPLIT */ - nla_total_size(sizeof(u32)); /* _RINGS_CQE_SIZE */ + nla_total_size(sizeof(u32) + /* _RINGS_CQE_SIZE */ + nla_total_size(sizeof(u8))); /* _RINGS_TX_PUSH */ } static int rings_fill_reply(struct sk_buff *skb, @@ -94,7 +95,8 @@ static int rings_fill_reply(struct sk_buff *skb, (nla_put_u8(skb, ETHTOOL_A_RINGS_TCP_DATA_SPLIT, kr->tcp_data_split))) || (kr->cqe_size && - (nla_put_u32(skb, ETHTOOL_A_RINGS_CQE_SIZE, kr->cqe_size)))) + (nla_put_u32(skb, ETHTOOL_A_RINGS_CQE_SIZE, kr->cqe_size))) || + nla_put_u8(skb, ETHTOOL_A_RINGS_TX_PUSH, !!kr->tx_push)) return -EMSGSIZE; return 0; @@ -123,6 +125,7 @@ const struct nla_policy ethnl_rings_set_policy[] = { [ETHTOOL_A_RINGS_TX] = { .type = NLA_U32 }, [ETHTOOL_A_RINGS_RX_BUF_LEN] = NLA_POLICY_MIN(NLA_U32, 1), [ETHTOOL_A_RINGS_CQE_SIZE] = NLA_POLICY_MIN(NLA_U32, 1), + [ETHTOOL_A_RINGS_TX_PUSH] = NLA_POLICY_MAX(NLA_U8, 1), }; int ethnl_set_rings(struct sk_buff *skb, struct genl_info *info) @@ -149,6 +152,15 @@ int ethnl_set_rings(struct sk_buff *skb, struct genl_info *info) if (!ops->get_ringparam || !ops->set_ringparam) goto out_dev; + if (tb[ETHTOOL_A_RINGS_TX_PUSH] && + !(ops->supported_ring_params & ETHTOOL_RING_USE_TX_PUSH)) { + ret = -EOPNOTSUPP; + NL_SET_ERR_MSG_ATTR(info->extack, + tb[ETHTOOL_A_RINGS_TX_PUSH], + "setting tx push not supported"); + goto out_dev; + } + rtnl_lock(); ret = ethnl_ops_begin(dev); if (ret < 0) @@ -165,6 +177,8 @@ int ethnl_set_rings(struct sk_buff *skb, struct genl_info *info) tb[ETHTOOL_A_RINGS_RX_BUF_LEN], &mod); ethnl_update_u32(&kernel_ringparam.cqe_size, tb[ETHTOOL_A_RINGS_CQE_SIZE], &mod); + ethnl_update_u8(&kernel_ringparam.tx_push, + tb[ETHTOOL_A_RINGS_TX_PUSH], &mod); ret = 0; if (!mod) goto out_ops;