Re: [PATCH] tracing: use ring_buffer_record_is_set_on() in tracer_tracing_is_on()

From: Steven Rostedt
Date: Wed Feb 07 2024 - 06:10:03 EST


On Wed, 07 Feb 2024 06:50:59 +0100
Sven Schnelle <svens@xxxxxxxxxxxxx> wrote:

> Hi Steven,

> Not sure whether that is enough, have to test. However, it's not really
> a fix, it would just require a bit more load and the test would fail
> again. The fundamental problem is that even after disabling tracing
> there might be some tracing line added due to the lockless nature of
> the ringbuffer. This might then replace some existing cmdline entry.
> So maybe we should change the test to ignore the program name when
> calculating the checksums.

Have you figured out what caused the cmdlines to change when tracing is
off. It shouldn't be updated even with just 128 entries.

I'm also looking into a way to keep more of a LRU command lines around,
but nothing concrete yet.

-- Steve