Re: [PATCH v2 22/32] selftests/ftrace: Add ringbuffer size changing testcase
From: Masami Hiramatsu
Date: Thu Aug 30 2018 - 19:35:33 EST
On Thu, 30 Aug 2018 11:50:55 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> On Thu, 30 Aug 2018 16:12:18 +0900
> Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
> > > I'm fine with this, but one day I need to port over some of my other
> > > tests. I have a test that stresses the ring buffer size (basically
> > > checks to see if it can cause an oom). I need to port that to
> > > selftests. But for now...
> > Hmm, such stress test is not good for kselftest, since it can cause
> > oom and kill some test process. Maybe we should have such stresstest
> > framework (which allows test to crash kernel)
> The point of the test is to make sure that it doesn't kill
> everything :-) The ring buffer code is suppose to detect that it will
> cause an OOM, and if it does that's considered a failure.
Ah, OK, so the test itself must not cause OOM. That's reasonable. :)
> Just like any other test, if it fails, it can crash the kernel. But the
> ring buffer code is suppose to be able to keep the kernel from crashing
> (including triggering OOM) if the buffer size is stressed.
> Maybe I'll port that over today :-/
Looking forward it!
> -- Steve
Masami Hiramatsu <mhiramat@xxxxxxxxxx>