tree bb8e5cd1444a74ea283e3fa55607225e7fda4d70
parent 2a8247a2600c3e087a568fc68a6ec4eedac27ef1
author David Sharp <dhsharp@google.com> 1291844807 -0800
committer Steven Rostedt <rostedt@goodmis.org> 1299696747 -0500

tracing: Add an 'overwrite' trace_option.

Add an "overwrite" trace_option for ftrace to control whether the buffer should
be overwritten on overflow or not. The default remains to overwrite old events
when the buffer is full. This patch adds the option to instead discard newest
events when the buffer is full. This is useful to get a snapshot of traces just
after enabling traces. Dropping the current event is also a simpler code path.

Signed-off-by: David Sharp <dhsharp@google.com>
LKML-Reference: <1291844807-15481-1-git-send-email-dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>