devlink: Add health report functionality

Upon error discover, every driver can report it to the devlink health
mechanism via devlink_health_report function, using the appropriate
reporter registered to it. Driver can pass error specific context which
will be delivered to it as part of the dump / recovery callbacks.

Once an error is reported, devlink health will do the following actions:
* A log is being send to the kernel trace events buffer
* Health status and statistics are being updated for the reporter instance
* Object dump is being taken and stored at the reporter instance (as long
  as there is no other dump which is already stored)
* Auto recovery attempt is being done. Depends on:
  - Auto Recovery configuration
  - Grace period vs. Time since last recover

Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Moshe Shemesh <moshe@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/devlink.h

@@ -704,6 +704,8 @@ devlink_health_reporter_destroy(struct devlink_health_reporter *reporter);
 
 void *
 devlink_health_reporter_priv(struct devlink_health_reporter *reporter);
+int devlink_health_report(struct devlink_health_reporter *reporter,
+			  const char *msg, void *priv_ctx);
 
 #else
 
@@ -1173,6 +1175,13 @@ devlink_health_reporter_priv(struct devlink_health_reporter *reporter)
 {
 	return NULL;
 }
+
+static inline int
+devlink_health_report(struct devlink_health_reporter *reporter,
+		      const char *msg, void *priv_ctx)
+{
+	return 0;
+}
 #endif
 
 #if IS_REACHABLE(CONFIG_NET_DEVLINK)