From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cyril Hrubis Date: Mon, 14 Aug 2017 15:33:51 +0200 Subject: [LTP] [PATCH V2 1/2] ltp: Add the ability to specify the latency constraint In-Reply-To: References: <337916262.70548323.1502450718721.JavaMail.zimbra@redhat.com> <1502456086-14696-1-git-send-email-daniel.lezcano@linaro.org> <20170811140905.GB3341@rei.lan> <20170811152855.GA14152@rei.lan> Message-ID: <20170814133351.GA11524@rei> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it Hi! > > tests that should end up > > using the same timer with the same slack formula in kernel and hence > > should fail in the very same way. And possibly rest of the timer > > testcases should likely fail as well since these are not that > > different either. > > The latencies introduced by the kernel energy saving framework can make > these tests to fail and it is impossible to get rid of that, except by > setting the latency to zero when running specific test cases. > > > > Are you, by any chance, using latest stable release? Since we had > > rewritten all the timer precision tests recently in: > > > > https://github.com/linux-test-project/ltp/commit/c459654db64cd29177a382ab178fdd5ad59664e4 > > Yes, I am. That explains it. Previously each of the timer testcases had it's own PASS/FAIL criteria and each of them was slightly different. We got rid of that mess recetly and so the latest git has a timer measurement library and the test only defines a sampling function now. We also did quite a lot of testing to make sure that the test are stable now. And because of that we take more samples and apply discarded mean to get rid of random outliners. But we did most of the testing on x86 hardware so it's possible that it still needs some adjustements. Can you, please, try with the latest git to see if these tests works for you now? And then, in a case that they stil fail, we will figure out how to fix them. Most likely we will patch the timer test library, either to loosen the crieria or to keep the cpu_dma_latecy open while we sample the timers. -- Cyril Hrubis chrubis@suse.cz