[Crash-utility] [PATCH 04/12] crash-trace-command: load id for different kernels

[Lai Jiangshan]

The id field of struct ftrace_event_call is different for kernels:

Old kernel uses ftrace_event_call.id
newer kernel uses ftrace_event_call.event.type

Change ftrace_get_event_type_id() and make it serves for different kernels.

Signed-off-by: Lai Jiangshan <laijs at cn.fujitsu.com>
---
diff --git a/extensions/trace.c b/extensions/trace.c
index 3697108..1ad53c1 100755
--- a/extensions/trace.c
+++ b/extensions/trace.c
@@ -878,6 +878,15 @@ int ftrace_get_event_type_id(ulong call, int *id)
 	if (!inited) {
 		inited = 1;
 		id_offset = MEMBER_OFFSET("ftrace_event_call", "id");
+
+		if (id_offset < 0) {
+			/* id = call->event.type */
+			int f1 = MEMBER_OFFSET("ftrace_event_call", "event");
+			int f2 = MEMBER_OFFSET("trace_event", "type");
+
+			if (f1 >= 0 && f2 >= 0)
+				id_offset = f1 + f2;
+		}
 	}
 
 	if (id_offset < 0)