[RFC net-next 1/2] ethtool: add support for controling the type of adaptive coalescing

Huazhong Tan
2020-11-19T03:54:21Z

Since the information whether the adaptive behavior is implemented
by DIM or driver custom is useful, so add new attribute to
ETHTOOL_MSG_COALESCE_GET/ETHTOOL_MSG_COALESCE_SET commands to control
the type of adaptive coalescing.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
---
include/linux/ethtool.h | 1 +
include/uapi/linux/ethtool.h | 2 ++
include/uapi/linux/ethtool_netlink.h | 1 +
net/ethtool/coalesce.c | 11 +++++++++--
net/ethtool/netlink.h | 2 +-
5 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 6408b44..f57cb92 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -215,6 +215,7 @@ bool ethtool_convert_link_mode_to_legacy_u32(u32 *legacy_u32,
#define ETHTOOL_COALESCE_TX_USECS_HIGH BIT(19)
#define ETHTOOL_COALESCE_TX_MAX_FRAMES_HIGH BIT(20)
#define ETHTOOL_COALESCE_RATE_SAMPLE_INTERVAL BIT(21)
+#define ETHTOOL_COALESCE_USE_DIM BIT(22)

#define ETHTOOL_COALESCE_USECS \
(ETHTOOL_COALESCE_RX_USECS | ETHTOOL_COALESCE_TX_USECS)
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 9ca87bc..afd8de2 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -433,6 +433,7 @@ struct ethtool_modinfo {
* a TX interrupt, when the packet rate is above @pkt_rate_high.
* @rate_sample_interval: How often to do adaptive coalescing packet rate
* sampling, measured in seconds. Must not be zero.
+ * @use_dim: Use DIM for IRQ coalescing, if adaptive coalescing is enabled.
*
* Each pair of (usecs, max_frames) fields specifies that interrupts
* should be coalesced until
@@ -483,6 +484,7 @@ struct ethtool_coalesce {
__u32 tx_coalesce_usecs_high;
__u32 tx_max_coalesced_frames_high;
__u32 rate_sample_interval;
+ __u32 use_dim;
};

/**
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index e2bf36e..e3458d9 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -366,6 +366,7 @@ enum {
ETHTOOL_A_COALESCE_TX_USECS_HIGH, /* u32 */
ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH, /* u32 */
ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL, /* u32 */
+ ETHTOOL_A_COALESCE_USE_DIM, /* u8 */

/* add new constants above here */
__ETHTOOL_A_COALESCE_CNT,
diff --git a/net/ethtool/coalesce.c b/net/ethtool/coalesce.c
index 1d6bc13..f12e5de 100644
--- a/net/ethtool/coalesce.c
+++ b/net/ethtool/coalesce.c
@@ -50,6 +50,7 @@ __CHECK_SUPPORTED_OFFSET(COALESCE_RX_MAX_FRAMES_HIGH);
__CHECK_SUPPORTED_OFFSET(COALESCE_TX_USECS_HIGH);
__CHECK_SUPPORTED_OFFSET(COALESCE_TX_MAX_FRAMES_HIGH);
__CHECK_SUPPORTED_OFFSET(COALESCE_RATE_SAMPLE_INTERVAL);
+__CHECK_SUPPORTED_OFFSET(COALESCE_USE_DIM);

const struct nla_policy ethnl_coalesce_get_policy[] = {
[ETHTOOL_A_COALESCE_HEADER] =
@@ -100,7 +101,8 @@ static int coalesce_reply_size(const struct ethnl_req_info *req_base,
nla_total_size(sizeof(u32)) + /* _RX_MAX_FRAMES_HIGH */
nla_total_size(sizeof(u32)) + /* _TX_USECS_HIGH */
nla_total_size(sizeof(u32)) + /* _TX_MAX_FRAMES_HIGH */
- nla_total_size(sizeof(u32)); /* _RATE_SAMPLE_INTERVAL */
+ nla_total_size(sizeof(u32)) + /* _RATE_SAMPLE_INTERVAL */
+ nla_total_size(sizeof(u8)); /* _USE_DIM */
}

static bool coalesce_put_u32(struct sk_buff *skb, u16 attr_type, u32 val,
@@ -170,7 +172,9 @@ static int coalesce_fill_reply(struct sk_buff *skb,
coalesce_put_u32(skb, ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH,
coal->tx_max_coalesced_frames_high, supported) ||
coalesce_put_u32(skb, ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL,
- coal->rate_sample_interval, supported))
+ coal->rate_sample_interval, supported) ||
+ coalesce_put_bool(skb, ETHTOOL_A_COALESCE_USE_DIM,
+ coal->use_dim, supported))
return -EMSGSIZE;

return 0;
@@ -215,6 +219,7 @@ const struct nla_policy ethnl_coalesce_set_policy[] = {
[ETHTOOL_A_COALESCE_TX_USECS_HIGH] = { .type = NLA_U32 },
[ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH] = { .type = NLA_U32 },
[ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL] = { .type = NLA_U32 },
+ [ETHTOOL_A_COALESCE_USE_DIM] = { .type = NLA_U8 },
};

int ethnl_set_coalesce(struct sk_buff *skb, struct genl_info *info)
@@ -303,6 +308,8 @@ int ethnl_set_coalesce(struct sk_buff *skb, struct genl_info *info)
tb[ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH], &mod);
ethnl_update_u32(&coalesce.rate_sample_interval,
tb[ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL], &mod);
+ ethnl_update_bool32(&coalesce.use_dim,
+ tb[ETHTOOL_A_COALESCE_USE_DIM], &mod);
ret = 0;
if (!mod)
goto out_ops;
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index d8efec5..e63f44a 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -366,7 +366,7 @@ extern const struct nla_policy ethnl_rings_set_policy[ETHTOOL_A_RINGS_TX + 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];
-extern const struct nla_policy ethnl_coalesce_set_policy[ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL + 1];
+extern const struct nla_policy ethnl_coalesce_set_policy[ETHTOOL_A_COALESCE_USE_DIM + 1];
extern const struct nla_policy ethnl_pause_get_policy[ETHTOOL_A_PAUSE_HEADER + 1];
extern const struct nla_policy ethnl_pause_set_policy[ETHTOOL_A_PAUSE_TX + 1];
extern const struct nla_policy ethnl_eee_get_policy[ETHTOOL_A_EEE_HEADER + 1];
--
2.7.4