xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

tracing: Add an 'overwrite' trace_option.

Browse Source 
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>
This commit is contained in:
David Sharp
2010-12-08 13:46:47 -08:00
committed by Steven Rostedt
parent 2a8247a260
commit 750912fa36
5 changed files with 30 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
include/linux/ring_buffer.h
View File

@@ -100,6 +100,8 @@ void ring_buffer_free(struct ring_buffer *buffer);
int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size);
void ring_buffer_change_overwrite(struct ring_buffer *buffer, int val);
struct ring_buffer_event *ring_buffer_lock_reserve(struct ring_buffer *buffer,
unsigned long length);
int ring_buffer_unlock_commit(struct ring_buffer *buffer,