From: Andrew Melnychenko <andrew@daynix.com>
To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org
Cc: mst@redhat.com, yuri.benditovich@daynix.com, yan@daynix.com,
kuba@kernel.org, davem@davemloft.net
Subject: [PATCH v5 4/4] drivers/net/virtio_net: Added RSS hash report control.
Date: Mon, 28 Mar 2022 20:53:36 +0300 [thread overview]
Message-ID: <20220328175336.10802-5-andrew@daynix.com> (raw)
In-Reply-To: <20220328175336.10802-1-andrew@daynix.com>
Now it's possible to control supported hashflows.
Added hashflow set/get callbacks.
Also, disabling RXH_IP_SRC/DST for TCP would disable then for UDP.
TCP and UDP supports only:
ethtool -U eth0 rx-flow-hash tcp4 sd
RXH_IP_SRC + RXH_IP_DST
ethtool -U eth0 rx-flow-hash tcp4 sdfn
RXH_IP_SRC + RXH_IP_DST + RXH_L4_B_0_1 + RXH_L4_B_2_3
Disabling happens because VirtioNET hashtype for IP doesn't check L4 proto,
it works for all IP packets(TCP, UDP, ICMP, etc.).
For TCP and UDP, it's possible to set IP+PORT hashes.
But disabling IP hashes will disable them for TCP and UDP simultaneously.
It's possible to set IP+PORT for TCP/UDP and disable/enable IP
for everything else(UDP, ICMP, etc.).
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
drivers/net/virtio_net.c | 141 ++++++++++++++++++++++++++++++++++++++-
1 file changed, 140 insertions(+), 1 deletion(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index c9472c30e8a2..17eeb4f807e3 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -231,6 +231,7 @@ struct virtnet_info {
u8 rss_key_size;
u16 rss_indir_table_size;
u32 rss_hash_types_supported;
+ u32 rss_hash_types_saved;
/* Has control virtqueue */
bool has_cvq;
@@ -2278,6 +2279,7 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
int i = 0;
vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+ vi->rss_hash_types_saved = vi->rss_hash_types_supported;
vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size
? vi->rss_indir_table_size - 1 : 0;
vi->ctrl->rss.unclassified_queue = 0;
@@ -2293,6 +2295,121 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
}
+static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info)
+{
+ info->data = 0;
+ switch (info->flow_type) {
+ case TCP_V4_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case TCP_V6_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case UDP_V4_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case UDP_V6_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case IPV4_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+
+ break;
+ case IPV6_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6)
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+
+ break;
+ default:
+ info->data = 0;
+ break;
+ }
+}
+
+static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info)
+{
+ u32 new_hashtypes = vi->rss_hash_types_saved;
+ bool is_disable = info->data & RXH_DISCARD;
+ bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3);
+
+ /* supports only 'sd', 'sdfn' and 'r' */
+ if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable))
+ return false;
+
+ switch (info->flow_type) {
+ case TCP_V4_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0);
+ break;
+ case UDP_V4_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0);
+ break;
+ case IPV4_FLOW:
+ new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+ if (!is_disable)
+ new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+ break;
+ case TCP_V6_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0);
+ break;
+ case UDP_V6_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0);
+ break;
+ case IPV6_FLOW:
+ new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+ if (!is_disable)
+ new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+ break;
+ default:
+ /* unsupported flow */
+ return false;
+ }
+
+ /* if unsupported hashtype was set */
+ if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported))
+ return false;
+
+ if (new_hashtypes != vi->rss_hash_types_saved) {
+ vi->rss_hash_types_saved = new_hashtypes;
+ vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
+ if (vi->dev->features & NETIF_F_RXHASH)
+ return virtnet_commit_rss_command(vi);
+ }
+
+ return true;
+}
static void virtnet_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
@@ -2578,6 +2695,27 @@ static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
switch (info->cmd) {
case ETHTOOL_GRXRINGS:
info->data = vi->curr_queue_pairs;
+ break;
+ case ETHTOOL_GRXFH:
+ virtnet_get_hashflow(vi, info);
+ break;
+ default:
+ rc = -EOPNOTSUPP;
+ }
+
+ return rc;
+}
+
+static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ int rc = 0;
+
+ switch (info->cmd) {
+ case ETHTOOL_SRXFH:
+ if (!virtnet_set_hashflow(vi, info))
+ rc = -EINVAL;
+
break;
default:
rc = -EOPNOTSUPP;
@@ -2606,6 +2744,7 @@ static const struct ethtool_ops virtnet_ethtool_ops = {
.get_rxfh = virtnet_get_rxfh,
.set_rxfh = virtnet_set_rxfh,
.get_rxnfc = virtnet_get_rxnfc,
+ .set_rxnfc = virtnet_set_rxnfc,
};
static void virtnet_freeze_down(struct virtio_device *vdev)
@@ -2860,7 +2999,7 @@ static int virtnet_set_features(struct net_device *dev,
if ((dev->features ^ features) & NETIF_F_RXHASH) {
if (features & NETIF_F_RXHASH)
- vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+ vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
else
vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
--
2.35.1
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
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WARNING: multiple messages have this Message-ID (diff)
From: Andrew Melnychenko <andrew@daynix.com>
To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org
Cc: kuba@kernel.org, davem@davemloft.net, jasowang@redhat.com,
mst@redhat.com, yan@daynix.com, yuri.benditovich@daynix.com
Subject: [PATCH v5 4/4] drivers/net/virtio_net: Added RSS hash report control.
Date: Mon, 28 Mar 2022 20:53:36 +0300 [thread overview]
Message-ID: <20220328175336.10802-5-andrew@daynix.com> (raw)
In-Reply-To: <20220328175336.10802-1-andrew@daynix.com>
Now it's possible to control supported hashflows.
Added hashflow set/get callbacks.
Also, disabling RXH_IP_SRC/DST for TCP would disable then for UDP.
TCP and UDP supports only:
ethtool -U eth0 rx-flow-hash tcp4 sd
RXH_IP_SRC + RXH_IP_DST
ethtool -U eth0 rx-flow-hash tcp4 sdfn
RXH_IP_SRC + RXH_IP_DST + RXH_L4_B_0_1 + RXH_L4_B_2_3
Disabling happens because VirtioNET hashtype for IP doesn't check L4 proto,
it works for all IP packets(TCP, UDP, ICMP, etc.).
For TCP and UDP, it's possible to set IP+PORT hashes.
But disabling IP hashes will disable them for TCP and UDP simultaneously.
It's possible to set IP+PORT for TCP/UDP and disable/enable IP
for everything else(UDP, ICMP, etc.).
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
drivers/net/virtio_net.c | 141 ++++++++++++++++++++++++++++++++++++++-
1 file changed, 140 insertions(+), 1 deletion(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index c9472c30e8a2..17eeb4f807e3 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -231,6 +231,7 @@ struct virtnet_info {
u8 rss_key_size;
u16 rss_indir_table_size;
u32 rss_hash_types_supported;
+ u32 rss_hash_types_saved;
/* Has control virtqueue */
bool has_cvq;
@@ -2278,6 +2279,7 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
int i = 0;
vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+ vi->rss_hash_types_saved = vi->rss_hash_types_supported;
vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size
? vi->rss_indir_table_size - 1 : 0;
vi->ctrl->rss.unclassified_queue = 0;
@@ -2293,6 +2295,121 @@ static void virtnet_init_default_rss(struct virtnet_info *vi)
netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
}
+static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info)
+{
+ info->data = 0;
+ switch (info->flow_type) {
+ case TCP_V4_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case TCP_V6_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case UDP_V4_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case UDP_V6_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3;
+ } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+ }
+ break;
+ case IPV4_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+
+ break;
+ case IPV6_FLOW:
+ if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6)
+ info->data = RXH_IP_SRC | RXH_IP_DST;
+
+ break;
+ default:
+ info->data = 0;
+ break;
+ }
+}
+
+static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info)
+{
+ u32 new_hashtypes = vi->rss_hash_types_saved;
+ bool is_disable = info->data & RXH_DISCARD;
+ bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3);
+
+ /* supports only 'sd', 'sdfn' and 'r' */
+ if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable))
+ return false;
+
+ switch (info->flow_type) {
+ case TCP_V4_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0);
+ break;
+ case UDP_V4_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0);
+ break;
+ case IPV4_FLOW:
+ new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+ if (!is_disable)
+ new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+ break;
+ case TCP_V6_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0);
+ break;
+ case UDP_V6_FLOW:
+ new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
+ if (!is_disable)
+ new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+ | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0);
+ break;
+ case IPV6_FLOW:
+ new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+ if (!is_disable)
+ new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+ break;
+ default:
+ /* unsupported flow */
+ return false;
+ }
+
+ /* if unsupported hashtype was set */
+ if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported))
+ return false;
+
+ if (new_hashtypes != vi->rss_hash_types_saved) {
+ vi->rss_hash_types_saved = new_hashtypes;
+ vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
+ if (vi->dev->features & NETIF_F_RXHASH)
+ return virtnet_commit_rss_command(vi);
+ }
+
+ return true;
+}
static void virtnet_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
@@ -2578,6 +2695,27 @@ static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
switch (info->cmd) {
case ETHTOOL_GRXRINGS:
info->data = vi->curr_queue_pairs;
+ break;
+ case ETHTOOL_GRXFH:
+ virtnet_get_hashflow(vi, info);
+ break;
+ default:
+ rc = -EOPNOTSUPP;
+ }
+
+ return rc;
+}
+
+static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ int rc = 0;
+
+ switch (info->cmd) {
+ case ETHTOOL_SRXFH:
+ if (!virtnet_set_hashflow(vi, info))
+ rc = -EINVAL;
+
break;
default:
rc = -EOPNOTSUPP;
@@ -2606,6 +2744,7 @@ static const struct ethtool_ops virtnet_ethtool_ops = {
.get_rxfh = virtnet_get_rxfh,
.set_rxfh = virtnet_set_rxfh,
.get_rxnfc = virtnet_get_rxnfc,
+ .set_rxnfc = virtnet_set_rxnfc,
};
static void virtnet_freeze_down(struct virtio_device *vdev)
@@ -2860,7 +2999,7 @@ static int virtnet_set_features(struct net_device *dev,
if ((dev->features ^ features) & NETIF_F_RXHASH) {
if (features & NETIF_F_RXHASH)
- vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+ vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
else
vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
--
2.35.1
next prev parent reply other threads:[~2022-03-28 18:01 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-28 17:53 [PATCH v5 0/4] RSS support for VirtioNet Andrew Melnychenko
2022-03-28 17:53 ` Andrew Melnychenko
2022-03-28 17:53 ` [PATCH v5 1/4] drivers/net/virtio_net: Fixed padded vheader to use v1 with hash Andrew Melnychenko
2022-03-28 17:53 ` Andrew Melnychenko
2022-03-28 17:53 ` [PATCH v5 2/4] drivers/net/virtio_net: Added basic RSS support Andrew Melnychenko
2022-03-28 17:53 ` Andrew Melnychenko
2022-03-28 17:53 ` [PATCH v5 3/4] drivers/net/virtio_net: Added RSS hash report Andrew Melnychenko
2022-03-28 17:53 ` Andrew Melnychenko
2022-08-11 8:53 ` Michael S. Tsirkin
2022-08-11 8:53 ` Michael S. Tsirkin
2022-03-28 17:53 ` Andrew Melnychenko [this message]
2022-03-28 17:53 ` [PATCH v5 4/4] drivers/net/virtio_net: Added RSS hash report control Andrew Melnychenko
2022-03-28 22:50 ` [PATCH v5 0/4] RSS support for VirtioNet Jakub Kicinski
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