[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <20221028012719.2702267-1-kuba@kernel.org>
Date: Thu, 27 Oct 2022 18:27:19 -0700
From: Jakub Kicinski <kuba@...nel.org>
To: davem@...emloft.net
Cc: netdev@...r.kernel.org, edumazet@...gle.com, pabeni@...hat.com,
Jakub Kicinski <kuba@...nel.org>, corbet@....net,
michael.chan@...adcom.com, andrew@...n.ch, hkallweit1@...il.com,
linux@...linux.org.uk, huangguangbin2@...wei.com,
chenhao288@...ilicon.com, moshet@...dia.com,
linux@...pel-privat.de, linux-doc@...r.kernel.org
Subject: [PATCH net-next v2] ethtool: linkstate: add a statistic for PHY down events
The previous attempt to augment carrier_down (see Link)
was not met with much enthusiasm so let's do the simple
thing of exposing what some devices already maintain.
Add a common ethtool statistic for link going down.
Currently users have to maintain per-driver mapping
to extract the right stat from the vendor-specific ethtool -S
stats. carrier_down does not fit the bill because it counts
a lot of software related false positives.
Add the statistic to the extended link state API to steer
vendors towards implementing all of it.
Implement for bnxt and all Linux-controlled PHYs. mlx5 and (possibly)
enic also have a counter for this but I leave the implementation
to their maintainers.
Link: https://lore.kernel.org/r/20220520004500.2250674-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@...nel.org>
---
The Linux PHY part is compile-tested only. Could anyone
(who's not at netdev conf?) help testing it?
v2:
- add the support for all Linux-driven PHYs
- LinkDownEvents -> link_down_events
v1: https://lore.kernel.org/all/20221026020948.1913777-1-kuba@kernel.org/
---
CC: corbet@....net
CC: michael.chan@...adcom.com
CC: andrew@...n.ch
CC: hkallweit1@...il.com
CC: linux@...linux.org.uk
CC: huangguangbin2@...wei.com
CC: chenhao288@...ilicon.com
CC: moshet@...dia.com
CC: linux@...pel-privat.de
CC: linux-doc@...r.kernel.org
---
Documentation/networking/ethtool-netlink.rst | 1 +
.../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 15 +++++++++++
drivers/net/phy/phy.c | 1 +
include/linux/ethtool.h | 14 +++++++++++
include/linux/phy.h | 3 +++
include/uapi/linux/ethtool_netlink.h | 2 ++
net/ethtool/linkstate.c | 25 ++++++++++++++++++-
7 files changed, 60 insertions(+), 1 deletion(-)
diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index d578b8bcd8a4..5454aa6c013c 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -491,6 +491,7 @@ any attributes.
``ETHTOOL_A_LINKSTATE_SQI_MAX`` u32 Max support SQI value
``ETHTOOL_A_LINKSTATE_EXT_STATE`` u8 link extended state
``ETHTOOL_A_LINKSTATE_EXT_SUBSTATE`` u8 link extended substate
+ ``ETHTOOL_A_LINKSTATE_EXT_DOWN_CNT`` u64 count of link down events
==================================== ====== ============================
For most NIC drivers, the value of ``ETHTOOL_A_LINKSTATE_LINK`` returns
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index cc89e5eabcb9..d8f0351df954 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -4112,6 +4112,20 @@ static void bnxt_get_rmon_stats(struct net_device *dev,
*ranges = bnxt_rmon_ranges;
}
+static void bnxt_get_link_ext_stats(struct net_device *dev,
+ struct ethtool_link_ext_stats *stats)
+{
+ struct bnxt *bp = netdev_priv(dev);
+ u64 *rx;
+
+ if (BNXT_VF(bp) || !(bp->flags & BNXT_FLAG_PORT_STATS_EXT))
+ return;
+
+ rx = bp->rx_port_stats_ext.sw_stats;
+ stats->link_down_events =
+ *(rx + BNXT_RX_STATS_EXT_OFFSET(link_down_events));
+}
+
void bnxt_ethtool_free(struct bnxt *bp)
{
kfree(bp->test_info);
@@ -4161,6 +4175,7 @@ const struct ethtool_ops bnxt_ethtool_ops = {
.get_eeprom = bnxt_get_eeprom,
.set_eeprom = bnxt_set_eeprom,
.get_link = bnxt_get_link,
+ .get_link_ext_stats = bnxt_get_link_ext_stats,
.get_eee = bnxt_get_eee,
.set_eee = bnxt_set_eee,
.get_module_info = bnxt_get_module_info,
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index e741d8aebffe..e5b6cb1a77f9 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -67,6 +67,7 @@ static void phy_link_down(struct phy_device *phydev)
{
phydev->phy_link_change(phydev, false);
phy_led_trigger_change_speed(phydev);
+ WRITE_ONCE(phydev->link_down_events, phydev->link_down_events + 1);
}
static const char *phy_pause_str(struct phy_device *phydev)
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 99dc7bfbcd3c..fa8e0d52dd30 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -125,6 +125,17 @@ struct ethtool_link_ext_state_info {
};
};
+struct ethtool_link_ext_stats {
+ /* Custom Linux statistic for PHY level link down events.
+ * In a simpler world it should be equal to netdev->carrier_down_count
+ * unfortunately netdev also counts local reconfigurations which don't
+ * actually take the physical link down, not to mention NC-SI which,
+ * if present, keeps the link up regardless of host state.
+ * This statistic counts when PHY _actually_ went down, or lost link.
+ */
+ u64 link_down_events;
+};
+
/**
* ethtool_rxfh_indir_default - get default value for RX flow hash indirection
* @index: Index in RX flow hash indirection table
@@ -481,6 +492,7 @@ struct ethtool_module_power_mode_params {
* do not attach ext_substate attribute to netlink message). If link_ext_state
* and link_ext_substate are unknown, return -ENODATA. If not implemented,
* link_ext_state and link_ext_substate will not be sent to userspace.
+ * @get_link_ext_stats: Read extra link-related counters.
* @get_eeprom_len: Read range of EEPROM addresses for validation of
* @get_eeprom and @set_eeprom requests.
* Returns 0 if device does not support EEPROM access.
@@ -652,6 +664,8 @@ struct ethtool_ops {
u32 (*get_link)(struct net_device *);
int (*get_link_ext_state)(struct net_device *,
struct ethtool_link_ext_state_info *);
+ void (*get_link_ext_stats)(struct net_device *,
+ struct ethtool_link_ext_stats *);
int (*get_eeprom_len)(struct net_device *);
int (*get_eeprom)(struct net_device *,
struct ethtool_eeprom *, u8 *);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index ddf66198f751..9a3752c0c444 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -600,6 +600,7 @@ struct macsec_ops;
* @psec: Pointer to Power Sourcing Equipment control struct
* @lock: Mutex for serialization access to PHY
* @state_queue: Work queue for state machine
+ * @link_down_events: Number of times link was lost
* @shared: Pointer to private data shared by phys in one package
* @priv: Pointer to driver private data
*
@@ -723,6 +724,8 @@ struct phy_device {
int pma_extable;
+ unsigned int link_down_events;
+
void (*phy_link_change)(struct phy_device *phydev, bool up);
void (*adjust_link)(struct net_device *dev);
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index bb57084ac524..8167848983d0 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -262,6 +262,8 @@ enum {
ETHTOOL_A_LINKSTATE_SQI_MAX, /* u32 */
ETHTOOL_A_LINKSTATE_EXT_STATE, /* u8 */
ETHTOOL_A_LINKSTATE_EXT_SUBSTATE, /* u8 */
+ ETHTOOL_A_LINKSTATE_PAD,
+ ETHTOOL_A_LINKSTATE_EXT_DOWN_CNT, /* u64 */
/* add new constants above here */
__ETHTOOL_A_LINKSTATE_CNT,
diff --git a/net/ethtool/linkstate.c b/net/ethtool/linkstate.c
index fb676f349455..7276ff752b80 100644
--- a/net/ethtool/linkstate.c
+++ b/net/ethtool/linkstate.c
@@ -13,6 +13,7 @@ struct linkstate_reply_data {
int link;
int sqi;
int sqi_max;
+ struct ethtool_link_ext_stats link_stats;
bool link_ext_state_provided;
struct ethtool_link_ext_state_info ethtool_link_ext_state_info;
};
@@ -22,7 +23,7 @@ struct linkstate_reply_data {
const struct nla_policy ethnl_linkstate_get_policy[] = {
[ETHTOOL_A_LINKSTATE_HEADER] =
- NLA_POLICY_NESTED(ethnl_header_policy),
+ NLA_POLICY_NESTED(ethnl_header_policy_stats),
};
static int linkstate_get_sqi(struct net_device *dev)
@@ -107,6 +108,19 @@ static int linkstate_prepare_data(const struct ethnl_req_info *req_base,
goto out;
}
+ ethtool_stats_init((u64 *)&data->link_stats,
+ sizeof(data->link_stats) / 8);
+
+ if (req_base->flags & ETHTOOL_FLAG_STATS) {
+ if (dev->phydev)
+ data->link_stats.link_down_events =
+ READ_ONCE(dev->phydev->link_down_events);
+
+ if (dev->ethtool_ops->get_link_ext_stats)
+ dev->ethtool_ops->get_link_ext_stats(dev,
+ &data->link_stats);
+ }
+
ret = 0;
out:
ethnl_ops_complete(dev);
@@ -134,6 +148,9 @@ static int linkstate_reply_size(const struct ethnl_req_info *req_base,
if (data->ethtool_link_ext_state_info.__link_ext_substate)
len += nla_total_size(sizeof(u8)); /* LINKSTATE_EXT_SUBSTATE */
+ if (data->link_stats.link_down_events != ETHTOOL_STAT_NOT_SET)
+ len += nla_total_size_64bit(sizeof(u64));
+
return len;
}
@@ -166,6 +183,12 @@ static int linkstate_fill_reply(struct sk_buff *skb,
return -EMSGSIZE;
}
+ if (data->link_stats.link_down_events != ETHTOOL_STAT_NOT_SET)
+ if (nla_put_u64_64bit(skb, ETHTOOL_A_LINKSTATE_EXT_DOWN_CNT,
+ data->link_stats.link_down_events,
+ ETHTOOL_A_LINKSTATE_PAD))
+ return -EMSGSIZE;
+
return 0;
}
--
2.37.3
Powered by blists - more mailing lists