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-rw-r--r--Documentation/networking/netconsole.rst5
-rw-r--r--drivers/net/netconsole.c60
-rw-r--r--include/linux/netpoll.h2
-rw-r--r--net/core/netpoll.c6
4 files changed, 64 insertions, 9 deletions
diff --git a/Documentation/networking/netconsole.rst b/Documentation/networking/netconsole.rst
index d55c2a22ec7a..94c4680fdf3e 100644
--- a/Documentation/networking/netconsole.rst
+++ b/Documentation/networking/netconsole.rst
@@ -124,7 +124,7 @@ To remove a target::
The interface exposes these parameters of a netconsole target to userspace:
- ============== ================================= ============
+ =============== ================================= ============
enabled Is this target currently enabled? (read-write)
extended Extended mode enabled (read-write)
release Prepend kernel release to message (read-write)
@@ -135,7 +135,8 @@ The interface exposes these parameters of a netconsole target to userspace:
remote_ip Remote agent's IP address (read-write)
local_mac Local interface's MAC address (read-only)
remote_mac Remote agent's MAC address (read-write)
- ============== ================================= ============
+ transmit_errors Number of packet send errors (read-only)
+ =============== ================================= ============
The "enabled" attribute is also used to control whether the parameters of
a target can be updated or not -- you can modify the parameters of only
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 4ea44a2f48f7..f422a2f666ef 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -36,6 +36,7 @@
#include <linux/inet.h>
#include <linux/configfs.h>
#include <linux/etherdevice.h>
+#include <linux/u64_stats_sync.h>
#include <linux/utsname.h>
#include <linux/rtnetlink.h>
@@ -90,6 +91,12 @@ static DEFINE_MUTEX(target_cleanup_list_lock);
*/
static struct console netconsole_ext;
+struct netconsole_target_stats {
+ u64_stats_t xmit_drop_count;
+ u64_stats_t enomem_count;
+ struct u64_stats_sync syncp;
+};
+
/**
* struct netconsole_target - Represents a configured netconsole target.
* @list: Links this target into the target_list.
@@ -97,6 +104,7 @@ static struct console netconsole_ext;
* @userdata_group: Links to the userdata configfs hierarchy
* @userdata_complete: Cached, formatted string of append
* @userdata_length: String length of userdata_complete
+ * @stats: Packet send stats for the target. Used for debugging.
* @enabled: On / off knob to enable / disable target.
* Visible from userspace (read-write).
* We maintain a strict 1:1 correspondence between this and
@@ -124,6 +132,7 @@ struct netconsole_target {
char userdata_complete[MAX_USERDATA_ENTRY_LENGTH * MAX_USERDATA_ITEMS];
size_t userdata_length;
#endif
+ struct netconsole_target_stats stats;
bool enabled;
bool extended;
bool release;
@@ -262,6 +271,7 @@ static void netconsole_process_cleanups_core(void)
* | remote_ip
* | local_mac
* | remote_mac
+ * | transmit_errors
* | userdata/
* | <key>/
* | value
@@ -371,6 +381,21 @@ static ssize_t remote_mac_show(struct config_item *item, char *buf)
return sysfs_emit(buf, "%pM\n", to_target(item)->np.remote_mac);
}
+static ssize_t transmit_errors_show(struct config_item *item, char *buf)
+{
+ struct netconsole_target *nt = to_target(item);
+ u64 xmit_drop_count, enomem_count;
+ unsigned int start;
+
+ do {
+ start = u64_stats_fetch_begin(&nt->stats.syncp);
+ xmit_drop_count = u64_stats_read(&nt->stats.xmit_drop_count);
+ enomem_count = u64_stats_read(&nt->stats.enomem_count);
+ } while (u64_stats_fetch_retry(&nt->stats.syncp, start));
+
+ return sysfs_emit(buf, "%llu\n", xmit_drop_count + enomem_count);
+}
+
/*
* This one is special -- targets created through the configfs interface
* are not enabled (and the corresponding netpoll activated) by default.
@@ -842,6 +867,7 @@ CONFIGFS_ATTR(, remote_ip);
CONFIGFS_ATTR_RO(, local_mac);
CONFIGFS_ATTR(, remote_mac);
CONFIGFS_ATTR(, release);
+CONFIGFS_ATTR_RO(, transmit_errors);
static struct configfs_attribute *netconsole_target_attrs[] = {
&attr_enabled,
@@ -854,6 +880,7 @@ static struct configfs_attribute *netconsole_target_attrs[] = {
&attr_remote_ip,
&attr_local_mac,
&attr_remote_mac,
+ &attr_transmit_errors,
NULL,
};
@@ -1058,6 +1085,33 @@ static struct notifier_block netconsole_netdev_notifier = {
.notifier_call = netconsole_netdev_event,
};
+/**
+ * send_udp - Wrapper for netpoll_send_udp that counts errors
+ * @nt: target to send message to
+ * @msg: message to send
+ * @len: length of message
+ *
+ * Calls netpoll_send_udp and classifies the return value. If an error
+ * occurred it increments statistics in nt->stats accordingly.
+ * Only calls netpoll_send_udp if CONFIG_NETCONSOLE_DYNAMIC is disabled.
+ */
+static void send_udp(struct netconsole_target *nt, const char *msg, int len)
+{
+ int result = netpoll_send_udp(&nt->np, msg, len);
+
+ if (IS_ENABLED(CONFIG_NETCONSOLE_DYNAMIC)) {
+ if (result == NET_XMIT_DROP) {
+ u64_stats_update_begin(&nt->stats.syncp);
+ u64_stats_inc(&nt->stats.xmit_drop_count);
+ u64_stats_update_end(&nt->stats.syncp);
+ } else if (result == -ENOMEM) {
+ u64_stats_update_begin(&nt->stats.syncp);
+ u64_stats_inc(&nt->stats.enomem_count);
+ u64_stats_update_end(&nt->stats.syncp);
+ }
+ }
+}
+
static void send_msg_no_fragmentation(struct netconsole_target *nt,
const char *msg,
int msg_len,
@@ -1085,7 +1139,7 @@ static void send_msg_no_fragmentation(struct netconsole_target *nt,
MAX_PRINT_CHUNK - msg_len,
"%s", userdata);
- netpoll_send_udp(&nt->np, buf, msg_len);
+ send_udp(nt, buf, msg_len);
}
static void append_release(char *buf)
@@ -1178,7 +1232,7 @@ static void send_fragmented_body(struct netconsole_target *nt, char *buf,
this_offset += this_chunk;
}
- netpoll_send_udp(&nt->np, buf, this_header + this_offset);
+ send_udp(nt, buf, this_header + this_offset);
offset += this_offset;
}
}
@@ -1288,7 +1342,7 @@ static void write_msg(struct console *con, const char *msg, unsigned int len)
tmp = msg;
for (left = len; left;) {
frag = min(left, MAX_PRINT_CHUNK);
- netpoll_send_udp(&nt->np, tmp, frag);
+ send_udp(nt, tmp, frag);
tmp += frag;
left -= frag;
}
diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h
index b34301650c47..f91e50a76efd 100644
--- a/include/linux/netpoll.h
+++ b/include/linux/netpoll.h
@@ -57,7 +57,7 @@ static inline void netpoll_poll_disable(struct net_device *dev) { return; }
static inline void netpoll_poll_enable(struct net_device *dev) { return; }
#endif
-void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
+int netpoll_send_udp(struct netpoll *np, const char *msg, int len);
void netpoll_print_options(struct netpoll *np);
int netpoll_parse_options(struct netpoll *np, char *opt);
int __netpoll_setup(struct netpoll *np, struct net_device *ndev);
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 99e5aa9cc992..6f2647b000b8 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -390,7 +390,7 @@ netdev_tx_t netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
}
EXPORT_SYMBOL(netpoll_send_skb);
-void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
+int netpoll_send_udp(struct netpoll *np, const char *msg, int len)
{
int total_len, ip_len, udp_len;
struct sk_buff *skb;
@@ -414,7 +414,7 @@ void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
skb = find_skb(np, total_len + np->dev->needed_tailroom,
total_len - len);
if (!skb)
- return;
+ return -ENOMEM;
skb_copy_to_linear_data(skb, msg, len);
skb_put(skb, len);
@@ -490,7 +490,7 @@ void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
skb->dev = np->dev;
- netpoll_send_skb(np, skb);
+ return (int)netpoll_send_skb(np, skb);
}
EXPORT_SYMBOL(netpoll_send_udp);
generated by cgit (git 2.34.1) at 2025-06-14 05:12:18 +0000