netconsole: add taskname to extradata entry count

New SYSDATA_TASKNAME feature flag to track when taskname append is enabled.

Additional check in count_extradata_entries() to include taskname in
total, counting it as an entry in extradata. This function is used to
check if we are not overflowing the number of extradata items.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/netconsole.c

@@ -104,6 +104,8 @@ struct netconsole_target_stats  {
 enum sysdata_feature {
 	/* Populate the CPU that sends the message */
 	SYSDATA_CPU_NR = BIT(0),
+	/* Populate the task name (as in current->comm) in sysdata */
+	SYSDATA_TASKNAME = BIT(1),
 };
 
 /**
@@ -701,6 +703,8 @@ static size_t count_extradata_entries(struct netconsole_target *nt)
 	/* Plus sysdata entries */
 	if (nt->sysdata_fields & SYSDATA_CPU_NR)
 		entries += 1;
+	if (nt->sysdata_fields & SYSDATA_TASKNAME)
+		entries += 1;
 
 	return entries;
 }