[PATCH v3 net-next 04/12] net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC)

Vladimir Oltean
2023-01-17T09:04:12Z

IEEE 802.3-2018 clause 99 defines a MAC Merge sublayer which contains an
Express MAC and a Preemptable MAC. Both MACs are hidden to higher and
lower layers and visible as a single MAC (packet classification to eMAC
or pMAC on TX is done based on priority; classification on RX is done
based on SFD).

For devices which support a MAC Merge sublayer, it is desirable to
retrieve individual packet counters from the eMAC and the pMAC, as well
as aggregate statistics (their sum).

Introduce a new ETHTOOL_A_STATS_SRC attribute which is part of the
policy of ETHTOOL_MSG_STATS_GET and, and an ETHTOOL_A_PAUSE_STATS_SRC
which is part of the policy of ETHTOOL_MSG_PAUSE_GET (accepted when
ETHTOOL_FLAG_STATS is set in the common ethtool header). Both of these
take values from enum ethtool_mac_stats_src, defaulting to "aggregate"
in the absence of the attribute.

Existing drivers do not need to pay attention to this enum which was
added to all driver-facing structures, just the ones which report the
MAC merge layer as supported.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
v2->v3:
- rename enum ethtool_stats_src to enum ethtool_mac_stats_src
- rename ETHTOOL_STATS_SRC_* to ETHTOOL_MAC_STATS_SRC_*
- change how __ethtool_dev_mm_supported() is implemented
v1->v2: patch is new (Jakub's suggestion)

include/linux/ethtool.h | 9 ++++++
include/uapi/linux/ethtool.h | 18 +++++++++++
include/uapi/linux/ethtool_netlink.h | 3 ++
net/ethtool/common.h | 2 ++
net/ethtool/mm.c | 16 ++++++++++
net/ethtool/netlink.h | 4 +--
net/ethtool/pause.c | 48 ++++++++++++++++++++++++++++
net/ethtool/stats.c | 32 ++++++++++++++++++-
8 files changed, 129 insertions(+), 3 deletions(-)

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 37eba38da502..0ccba6612190 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -311,6 +311,7 @@ static inline void ethtool_stats_init(u64 *stats, unsigned int n)
* via a more targeted API.
*/
struct ethtool_eth_mac_stats {
+ enum ethtool_mac_stats_src src;
u64 FramesTransmittedOK;
u64 SingleCollisionFrames;
u64 MultipleCollisionFrames;
@@ -339,6 +340,7 @@ struct ethtool_eth_mac_stats {
* via a more targeted API.
*/
struct ethtool_eth_phy_stats {
+ enum ethtool_mac_stats_src src;
u64 SymbolErrorDuringCarrier;
};

@@ -346,6 +348,7 @@ struct ethtool_eth_phy_stats {
* via a more targeted API.
*/
struct ethtool_eth_ctrl_stats {
+ enum ethtool_mac_stats_src src;
u64 MACControlFramesTransmitted;
u64 MACControlFramesReceived;
u64 UnsupportedOpcodesReceived;
@@ -353,6 +356,8 @@ struct ethtool_eth_ctrl_stats {

/**
* struct ethtool_pause_stats - statistics for IEEE 802.3x pause frames
+ * @src: input field denoting whether stats should be queried from the eMAC or
+ * pMAC (if the MM layer is supported). To be ignored otherwise.
* @tx_pause_frames: transmitted pause frame count. Reported to user space
* as %ETHTOOL_A_PAUSE_STAT_TX_FRAMES.
*
@@ -366,6 +371,7 @@ struct ethtool_eth_ctrl_stats {
* from the standard.
*/
struct ethtool_pause_stats {
+ enum ethtool_mac_stats_src src;
u64 tx_pause_frames;
u64 rx_pause_frames;
};
@@ -417,6 +423,8 @@ struct ethtool_rmon_hist_range {

/**
* struct ethtool_rmon_stats - selected RMON (RFC 2819) statistics
+ * @src: input field denoting whether stats should be queried from the eMAC or
+ * pMAC (if the MM layer is supported). To be ignored otherwise.
* @undersize_pkts: Equivalent to `etherStatsUndersizePkts` from the RFC.
* @oversize_pkts: Equivalent to `etherStatsOversizePkts` from the RFC.
* @fragments: Equivalent to `etherStatsFragments` from the RFC.
@@ -432,6 +440,7 @@ struct ethtool_rmon_hist_range {
* ranges is left to the driver.
*/
struct ethtool_rmon_stats {
+ enum ethtool_mac_stats_src src;
u64 undersize_pkts;
u64 oversize_pkts;
u64 fragments;
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 529a93696ab6..f7fba0dc87e5 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -711,6 +711,24 @@ enum ethtool_stringset {
ETH_SS_COUNT
};

+/**
+ * enum ethtool_mac_stats_src - source of ethtool MAC statistics
+ * @ETHTOOL_MAC_STATS_SRC_AGGREGATE:
+ * if device supports a MAC merge layer, this retrieves the aggregate
+ * statistics of the eMAC and pMAC. Otherwise, it retrieves just the
+ * statistics of the single (express) MAC.
+ * @ETHTOOL_MAC_STATS_SRC_EMAC:
+ * if device supports a MM layer, this retrieves the eMAC statistics.
+ * Otherwise, it retrieves the statistics of the single (express) MAC.
+ * @ETHTOOL_MAC_STATS_SRC_PMAC:
+ * if device supports a MM layer, this retrieves the pMAC statistics.
+ */
+enum ethtool_mac_stats_src {
+ ETHTOOL_MAC_STATS_SRC_AGGREGATE,
+ ETHTOOL_MAC_STATS_SRC_EMAC,
+ ETHTOOL_MAC_STATS_SRC_PMAC,
+};
+
/**
* enum ethtool_module_power_mode_policy - plug-in module power mode policy
* @ETHTOOL_MODULE_POWER_MODE_POLICY_HIGH: Module is always in high power mode.
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 58af390823b0..ffb073c0dbb4 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -428,6 +428,7 @@ enum {
ETHTOOL_A_PAUSE_RX, /* u8 */
ETHTOOL_A_PAUSE_TX, /* u8 */
ETHTOOL_A_PAUSE_STATS, /* nest - _PAUSE_STAT_* */
+ ETHTOOL_A_PAUSE_STATS_SRC, /* u32 */

/* add new constants above here */
__ETHTOOL_A_PAUSE_CNT,
@@ -744,6 +745,8 @@ enum {

ETHTOOL_A_STATS_GRP, /* nest - _A_STATS_GRP_* */

+ ETHTOOL_A_STATS_SRC, /* u32 */
+
/* add new constants above here */
__ETHTOOL_A_STATS_CNT,
ETHTOOL_A_STATS_MAX = (__ETHTOOL_A_STATS_CNT - 1)
diff --git a/net/ethtool/common.h b/net/ethtool/common.h
index b1b9db810eca..28b8aaaf9bcb 100644
--- a/net/ethtool/common.h
+++ b/net/ethtool/common.h
@@ -54,4 +54,6 @@ int ethtool_get_module_info_call(struct net_device *dev,
int ethtool_get_module_eeprom_call(struct net_device *dev,
struct ethtool_eeprom *ee, u8 *data);

+bool __ethtool_dev_mm_supported(struct net_device *dev);
+
#endif /* _ETHTOOL_COMMON_H */
diff --git a/net/ethtool/mm.c b/net/ethtool/mm.c
index 0c8135393c14..7ebc4e82e83d 100644
--- a/net/ethtool/mm.c
+++ b/net/ethtool/mm.c
@@ -253,3 +253,19 @@ int ethnl_set_mm(struct sk_buff *skb, struct genl_info *info)
ethnl_parse_header_dev_put(&req_info);
return ret;
}
+
+/* Returns whether a given device supports the MAC merge layer
+ * (has an eMAC and a pMAC). Must be called under rtnl_lock() and
+ * ethnl_ops_begin().
+ */
+bool __ethtool_dev_mm_supported(struct net_device *dev)
+{
+ const struct ethtool_ops *ops = dev->ethtool_ops;
+ struct ethtool_mm_state state = {};
+ int ret = -EOPNOTSUPP;
+
+ if (ops && ops->get_mm)
+ ret = ops->get_mm(dev, &state);
+
+ return !!ret;
+}
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 60278485b00b..29aef39476eb 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -399,7 +399,7 @@ extern const struct nla_policy ethnl_channels_get_policy[ETHTOOL_A_CHANNELS_HEAD
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_MAX + 1];
-extern const struct nla_policy ethnl_pause_get_policy[ETHTOOL_A_PAUSE_HEADER + 1];
+extern const struct nla_policy ethnl_pause_get_policy[ETHTOOL_A_PAUSE_STATS_SRC + 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];
extern const struct nla_policy ethnl_eee_set_policy[ETHTOOL_A_EEE_TX_LPI_TIMER + 1];
@@ -410,7 +410,7 @@ extern const struct nla_policy ethnl_tunnel_info_get_policy[ETHTOOL_A_TUNNEL_INF
extern const struct nla_policy ethnl_fec_get_policy[ETHTOOL_A_FEC_HEADER + 1];
extern const struct nla_policy ethnl_fec_set_policy[ETHTOOL_A_FEC_AUTO + 1];
extern const struct nla_policy ethnl_module_eeprom_get_policy[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS + 1];
-extern const struct nla_policy ethnl_stats_get_policy[ETHTOOL_A_STATS_GROUPS + 1];
+extern const struct nla_policy ethnl_stats_get_policy[ETHTOOL_A_STATS_SRC + 1];
extern const struct nla_policy ethnl_phc_vclocks_get_policy[ETHTOOL_A_PHC_VCLOCKS_HEADER + 1];
extern const struct nla_policy ethnl_module_get_policy[ETHTOOL_A_MODULE_HEADER + 1];
extern const struct nla_policy ethnl_module_set_policy[ETHTOOL_A_MODULE_POWER_MODE_POLICY + 1];
diff --git a/net/ethtool/pause.c b/net/ethtool/pause.c
index a8c113d244db..e2be9e89c9d9 100644
--- a/net/ethtool/pause.c
+++ b/net/ethtool/pause.c
@@ -5,8 +5,12 @@

struct pause_req_info {
struct ethnl_req_info base;
+ enum ethtool_mac_stats_src src;
};

+#define PAUSE_REQINFO(__req_base) \
+ container_of(__req_base, struct pause_req_info, base)
+
struct pause_reply_data {
struct ethnl_reply_data base;
struct ethtool_pauseparam pauseparam;
@@ -19,13 +23,40 @@ struct pause_reply_data {
const struct nla_policy ethnl_pause_get_policy[] = {
[ETHTOOL_A_PAUSE_HEADER] =
NLA_POLICY_NESTED(ethnl_header_policy_stats),
+ [ETHTOOL_A_PAUSE_STATS_SRC] =
+ NLA_POLICY_MAX(NLA_U32, ETHTOOL_MAC_STATS_SRC_PMAC),
};

+static int pause_parse_request(struct ethnl_req_info *req_base,
+ struct nlattr **tb,
+ struct netlink_ext_ack *extack)
+{
+ enum ethtool_mac_stats_src src = ETHTOOL_MAC_STATS_SRC_AGGREGATE;
+ struct pause_req_info *req_info = PAUSE_REQINFO(req_base);
+
+ if (tb[ETHTOOL_A_PAUSE_STATS_SRC]) {
+ if (!(req_base->flags & ETHTOOL_FLAG_STATS)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "ETHTOOL_FLAG_STATS must be set when requesting a source of stats");
+ return -EINVAL;
+ }
+
+ src = nla_get_u32(tb[ETHTOOL_A_PAUSE_STATS_SRC]);
+ }
+
+ req_info->src = src;
+
+ return 0;
+}
+
static int pause_prepare_data(const struct ethnl_req_info *req_base,
struct ethnl_reply_data *reply_base,
struct genl_info *info)
{
+ const struct pause_req_info *req_info = PAUSE_REQINFO(req_base);
struct pause_reply_data *data = PAUSE_REPDATA(reply_base);
+ enum ethtool_mac_stats_src src = req_info->src;
+ struct netlink_ext_ack *extack = info->extack;
struct net_device *dev = reply_base->dev;
int ret;

@@ -34,14 +65,26 @@ static int pause_prepare_data(const struct ethnl_req_info *req_base,

ethtool_stats_init((u64 *)&data->pausestat,
sizeof(data->pausestat) / 8);
+ data->pausestat.src = src;

ret = ethnl_ops_begin(dev);
if (ret < 0)
return ret;
+
+ if ((src == ETHTOOL_MAC_STATS_SRC_EMAC ||
+ src == ETHTOOL_MAC_STATS_SRC_PMAC) &&
+ !__ethtool_dev_mm_supported(dev)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Device does not support MAC merge layer");
+ ethnl_ops_complete(dev);
+ return -EOPNOTSUPP;
+ }
+
dev->ethtool_ops->get_pauseparam(dev, &data->pauseparam);
if (req_base->flags & ETHTOOL_FLAG_STATS &&
dev->ethtool_ops->get_pause_stats)
dev->ethtool_ops->get_pause_stats(dev, &data->pausestat);
+
ethnl_ops_complete(dev);

return 0;
@@ -56,6 +99,7 @@ static int pause_reply_size(const struct ethnl_req_info *req_base,

if (req_base->flags & ETHTOOL_FLAG_STATS)
n += nla_total_size(0) + /* _PAUSE_STATS */
+ nla_total_size(sizeof(u32)) + /* _PAUSE_STATS_SRC */
nla_total_size_64bit(sizeof(u64)) * ETHTOOL_PAUSE_STAT_CNT;
return n;
}
@@ -77,6 +121,9 @@ static int pause_put_stats(struct sk_buff *skb,
const u16 pad = ETHTOOL_A_PAUSE_STAT_PAD;
struct nlattr *nest;

+ if (nla_put_u32(skb, ETHTOOL_A_PAUSE_STATS_SRC, pause_stats->src))
+ return -EMSGSIZE;
+
nest = nla_nest_start(skb, ETHTOOL_A_PAUSE_STATS);
if (!nest)
return -EMSGSIZE;
@@ -121,6 +168,7 @@ const struct ethnl_request_ops ethnl_pause_request_ops = {
.req_info_size = sizeof(struct pause_req_info),
.reply_data_size = sizeof(struct pause_reply_data),

+ .parse_request = pause_parse_request,
.prepare_data = pause_prepare_data,
.reply_size = pause_reply_size,
.fill_reply = pause_fill_reply,
diff --git a/net/ethtool/stats.c b/net/ethtool/stats.c
index a20e0a24ff61..26a70320e01d 100644
--- a/net/ethtool/stats.c
+++ b/net/ethtool/stats.c
@@ -7,6 +7,7 @@
struct stats_req_info {
struct ethnl_req_info base;
DECLARE_BITMAP(stat_mask, __ETHTOOL_STATS_CNT);
+ enum ethtool_mac_stats_src src;
};

#define STATS_REQINFO(__req_base) \
@@ -75,16 +76,19 @@ const char stats_rmon_names[__ETHTOOL_A_STATS_RMON_CNT][ETH_GSTRING_LEN] = {
[ETHTOOL_A_STATS_RMON_JABBER] = "etherStatsJabbers",
};

-const struct nla_policy ethnl_stats_get_policy[ETHTOOL_A_STATS_GROUPS + 1] = {
+const struct nla_policy ethnl_stats_get_policy[ETHTOOL_A_STATS_SRC + 1] = {
[ETHTOOL_A_STATS_HEADER] =
NLA_POLICY_NESTED(ethnl_header_policy),
[ETHTOOL_A_STATS_GROUPS] = { .type = NLA_NESTED },
+ [ETHTOOL_A_STATS_SRC] =
+ NLA_POLICY_MAX(NLA_U32, ETHTOOL_MAC_STATS_SRC_PMAC),
};

static int stats_parse_request(struct ethnl_req_info *req_base,
struct nlattr **tb,
struct netlink_ext_ack *extack)
{
+ enum ethtool_mac_stats_src src = ETHTOOL_MAC_STATS_SRC_AGGREGATE;
struct stats_req_info *req_info = STATS_REQINFO(req_base);
bool mod = false;
int err;
@@ -100,6 +104,11 @@ static int stats_parse_request(struct ethnl_req_info *req_base,
return -EINVAL;
}

+ if (tb[ETHTOOL_A_STATS_SRC])
+ src = nla_get_u32(tb[ETHTOOL_A_STATS_SRC]);
+
+ req_info->src = src;
+
return 0;
}

@@ -109,6 +118,8 @@ static int stats_prepare_data(const struct ethnl_req_info *req_base,
{
const struct stats_req_info *req_info = STATS_REQINFO(req_base);
struct stats_reply_data *data = STATS_REPDATA(reply_base);
+ enum ethtool_mac_stats_src src = req_info->src;
+ struct netlink_ext_ack *extack = info->extack;
struct net_device *dev = reply_base->dev;
int ret;

@@ -116,11 +127,25 @@ static int stats_prepare_data(const struct ethnl_req_info *req_base,
if (ret < 0)
return ret;

+ if ((src == ETHTOOL_MAC_STATS_SRC_EMAC ||
+ src == ETHTOOL_MAC_STATS_SRC_PMAC) &&
+ !__ethtool_dev_mm_supported(dev)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Device does not support MAC merge layer");
+ ethnl_ops_complete(dev);
+ return -EOPNOTSUPP;
+ }
+
/* Mark all stats as unset (see ETHTOOL_STAT_NOT_SET) to prevent them
* from being reported to user space in case driver did not set them.
*/
memset(&data->stats, 0xff, sizeof(data->stats));

+ data->phy_stats.src = src;
+ data->mac_stats.src = src;
+ data->ctrl_stats.src = src;
+ data->rmon_stats.src = src;
+
if (test_bit(ETHTOOL_STATS_ETH_PHY, req_info->stat_mask) &&
dev->ethtool_ops->get_eth_phy_stats)
dev->ethtool_ops->get_eth_phy_stats(dev, &data->phy_stats);
@@ -146,6 +171,8 @@ static int stats_reply_size(const struct ethnl_req_info *req_base,
unsigned int n_grps = 0, n_stats = 0;
int len = 0;

+ len += nla_total_size(sizeof(u32)); /* _STATS_SRC */
+
if (test_bit(ETHTOOL_STATS_ETH_PHY, req_info->stat_mask)) {
n_stats += sizeof(struct ethtool_eth_phy_stats) / sizeof(u64);
n_grps++;
@@ -379,6 +406,9 @@ static int stats_fill_reply(struct sk_buff *skb,
const struct stats_reply_data *data = STATS_REPDATA(reply_base);
int ret = 0;

+ if (nla_put_u32(skb, ETHTOOL_A_STATS_SRC, req_info->src))
+ return -EMSGSIZE;
+
if (!ret && test_bit(ETHTOOL_STATS_ETH_PHY, req_info->stat_mask))
ret = stats_put_stats(skb, data, ETHTOOL_STATS_ETH_PHY,
ETH_SS_STATS_ETH_PHY,
--
2.34.1