From mboxrd@z Thu Jan 1 00:00:00 1970 From: mhiramat at kernel.org (Masami Hiramatsu) Date: Fri, 31 Aug 2018 08:35:28 +0900 Subject: [PATCH v2 22/32] selftests/ftrace: Add ringbuffer size changing testcase In-Reply-To: <20180830115055.6a28054c@gandalf.local.home> References: <153443695002.23257.13628220023468200991.stgit@devbox> <153443757416.23257.9284862385646039929.stgit@devbox> <20180824191836.305ad740@gandalf.local.home> <20180830161218.e46affa5a84abd47c9cf2a39@kernel.org> <20180830115055.6a28054c@gandalf.local.home> Message-ID: <20180831083528.ae339a660d28a71e02f03ed4@kernel.org> On Thu, 30 Aug 2018 11:50:55 -0400 Steven Rostedt wrote: > On Thu, 30 Aug 2018 16:12:18 +0900 > Masami Hiramatsu 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! Thank you, > > > -- Steve -- Masami Hiramatsu From mboxrd@z Thu Jan 1 00:00:00 1970 From: mhiramat@kernel.org (Masami Hiramatsu) Date: Fri, 31 Aug 2018 08:35:28 +0900 Subject: [PATCH v2 22/32] selftests/ftrace: Add ringbuffer size changing testcase In-Reply-To: <20180830115055.6a28054c@gandalf.local.home> References: <153443695002.23257.13628220023468200991.stgit@devbox> <153443757416.23257.9284862385646039929.stgit@devbox> <20180824191836.305ad740@gandalf.local.home> <20180830161218.e46affa5a84abd47c9cf2a39@kernel.org> <20180830115055.6a28054c@gandalf.local.home> Message-ID: <20180831083528.ae339a660d28a71e02f03ed4@kernel.org> Content-Type: text/plain; charset="UTF-8" Message-ID: <20180830233528.S515EwAp5bycVsj3Xjvlq9PgkTvxVm3JrbdZO5qiJbA@z> On Thu, 30 Aug 2018 11:50:55 -0400 Steven Rostedt wrote: > On Thu, 30 Aug 2018 16:12:18 +0900 > Masami Hiramatsu 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! Thank you, > > > -- Steve -- Masami Hiramatsu