https://chrisarges.net/tags/testing/Recent content in Testing on Chris J ArgesHugoenThu, 13 Nov 2014 09:45:00 -0800https://chrisarges.net/posts/2014-11-13-using-gcovlcov-with-linux-kernel/Thu, 13 Nov 2014 09:45:00 -0800https://chrisarges.net/posts/2014-11-13-using-gcovlcov-with-linux-kernel/<p>GCOV/LCOV are amazing tools to figure out code coverage in the Linux kernel. It is fairly trivial to setup on your own machine. First, enable the following in your kernel configuration:</p> <div class="highlight"><pre tabindex="0" style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;-webkit-text-size-adjust:none;"><code class="language-bash" data-lang="bash"><span style="display:flex;"><span>CONFIG_GCOV_KERNEL<span style="color:#f92672">=</span>y </span></span><span style="display:flex;"><span>CONFIG_GCOV_PROFILE_ALL<span style="color:#f92672">=</span>y </span></span><span style="display:flex;"><span>CONFIG_GCOV_FORMAT_AUTODETECT<span style="color:#f92672">=</span>y </span></span></code></pre></div><p>Build the kernel and install headers/debug/images to your machine. Note there may be issues if you run this on a separate machine so consult the official <a href="https://www.kernel.org/doc/Documentation/gcov.txt" title="gcov docs">documentation</a> for additional information.</p> <p>Boot the machine with the instrumented kernel and use the following to verify GCOV_KERNEL was setup properly:</p>