[PATCH net-next v2 06/10] devlink: add devlink_dev_driver_name() helper and use it in trace events

From: Jiri Pirko <jiri@resnulli.us>
Date: 2026-02-25 13:34:33
Also in: linux-doc, linux-rdma, linux-trace-kernel
Reply to: Jiri Pirko, 2026-02-25

From: Jiri Pirko <redacted>

In preparation to dev-less devlinks, add devlink_dev_driver_name()
that safely returns the driver name or NULL, and use it in all trace
events. The trace __string() macro handles NULL via __string_src(),
recording "(null)".

Signed-off-by: Jiri Pirko <redacted>
---
v1->v2:
- added missing symbol export
---
 include/net/devlink.h          |  1 +
 include/trace/events/devlink.h | 12 ++++++------
 net/devlink/core.c             |  8 ++++++++
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 0afb0958b910..45dec7067a8e 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h

@@ -1613,6 +1613,7 @@ struct devlink *priv_to_devlink(void *priv);
 struct device *devlink_to_dev(const struct devlink *devlink);
 const char *devlink_bus_name(const struct devlink *devlink);
 const char *devlink_dev_name(const struct devlink *devlink);
+const char *devlink_dev_driver_name(const struct devlink *devlink);
 
 /* Devlink instance explicit locking */
 void devl_lock(struct devlink *devlink);

diff --git a/include/trace/events/devlink.h b/include/trace/events/devlink.h
index 32304ce9ad15..4f8edf77dfbe 100644
--- a/include/trace/events/devlink.h
+++ b/include/trace/events/devlink.h

@@ -23,7 +23,7 @@ TRACE_EVENT(devlink_hwmsg,
 	TP_STRUCT__entry(
 		__string(bus_name, devlink_bus_name(devlink))
 		__string(dev_name, devlink_dev_name(devlink))
-		__string(driver_name, devlink_to_dev(devlink)->driver->name)
+		__string(driver_name, devlink_dev_driver_name(devlink))
 		__field(bool, incoming)
 		__field(unsigned long, type)
 		__dynamic_array(u8, buf, len)

@@ -57,7 +57,7 @@ TRACE_EVENT(devlink_hwerr,
 	TP_STRUCT__entry(
 		__string(bus_name, devlink_bus_name(devlink))
 		__string(dev_name, devlink_dev_name(devlink))
-		__string(driver_name, devlink_to_dev(devlink)->driver->name)
+		__string(driver_name, devlink_dev_driver_name(devlink))
 		__field(int, err)
 		__string(msg, msg)
 		),

@@ -87,7 +87,7 @@ TRACE_EVENT(devlink_health_report,
 	TP_STRUCT__entry(
 		__string(bus_name, devlink_bus_name(devlink))
 		__string(dev_name, devlink_dev_name(devlink))
-		__string(driver_name, devlink_to_dev(devlink)->driver->name)
+		__string(driver_name, devlink_dev_driver_name(devlink))
 		__string(reporter_name, reporter_name)
 		__string(msg, msg)
 	),

@@ -118,7 +118,7 @@ TRACE_EVENT(devlink_health_recover_aborted,
 	TP_STRUCT__entry(
 		__string(bus_name, devlink_bus_name(devlink))
 		__string(dev_name, devlink_dev_name(devlink))
-		__string(driver_name, devlink_to_dev(devlink)->driver->name)
+		__string(driver_name, devlink_dev_driver_name(devlink))
 		__string(reporter_name, reporter_name)
 		__field(bool, health_state)
 		__field(u64, time_since_last_recover)

@@ -152,7 +152,7 @@ TRACE_EVENT(devlink_health_reporter_state_update,
 	TP_STRUCT__entry(
 		__string(bus_name, devlink_bus_name(devlink))
 		__string(dev_name, devlink_dev_name(devlink))
-		__string(driver_name, devlink_to_dev(devlink)->driver->name)
+		__string(driver_name, devlink_dev_driver_name(devlink))
 		__string(reporter_name, reporter_name)
 		__field(u8, new_state)
 	),

@@ -183,7 +183,7 @@ TRACE_EVENT(devlink_trap_report,
 	TP_STRUCT__entry(
 		__string(bus_name, devlink_bus_name(devlink))
 		__string(dev_name, devlink_dev_name(devlink))
-		__string(driver_name, devlink_to_dev(devlink)->driver->name)
+		__string(driver_name, devlink_dev_driver_name(devlink))
 		__string(trap_name, metadata->trap_name)
 		__string(trap_group_name, metadata->trap_group_name)
 		__array(char, input_dev_name, IFNAMSIZ)

diff --git a/net/devlink/core.c b/net/devlink/core.c
index 2dd6d45bec18..85ea5856d523 100644
--- a/net/devlink/core.c
+++ b/net/devlink/core.c

@@ -260,6 +260,14 @@ const char *devlink_dev_name(const struct devlink *devlink)
 }
 EXPORT_SYMBOL_GPL(devlink_dev_name);
 
+const char *devlink_dev_driver_name(const struct devlink *devlink)
+{
+	struct device *dev = devlink->dev;
+
+	return dev ? dev->driver->name : NULL;
+}
+EXPORT_SYMBOL_GPL(devlink_dev_driver_name);
+
 struct net *devlink_net(const struct devlink *devlink)
 {
 	return read_pnet(&devlink->_net);

-- 
2.51.1

`h`	back out one level
`j`	next message in thread / next series-diff position
`k`	previous message in thread / previous series-diff position
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help