From patchwork Wed Dec 13 01:02:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rae Moar X-Patchwork-Id: 754126 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="35b7wDiI" Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E229DD0 for ; Tue, 12 Dec 2023 17:02:27 -0800 (PST) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-db5416d0fccso4544384276.1 for ; Tue, 12 Dec 2023 17:02:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1702429347; x=1703034147; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=Q5lVM/dVKeVFErFd3K5fREWS3rUw2b6FfvKCy8RqIqw=; b=35b7wDiIAe5ALWKl2T7A/ZPjqEPfv8jasQy6+XoPJzR9nnFNYtFZOmRc2FKIa7Ypl8 VhOIkJ1MoQ2jwnuLMfmuzXfhCGM5n3kOMIqjIYx4qjwXrSGcqakVwFdiGei/HgxTuWZX HOHT+0wan4r5P9fgiwkVwGX1SZLgv7ZvcewzhoSt72c1KpB375K3O7nZsOLCk1T2KYAD IIXmxTqnSezpsTBHJiUizo9nf0ESrCMEuvRnSbF9Oj+HxkLc7/udGj/KhP2cE0Xk/eN/ BlUgpJDBlMqycWDGTRTEzEADMQw9Y5ouPQeCGJ/WsKE93kPvIkb618Uf4/muR+d4CuSG 71AA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702429347; x=1703034147; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Q5lVM/dVKeVFErFd3K5fREWS3rUw2b6FfvKCy8RqIqw=; b=i88wEmWbYi07fOpkFQla/7uzzWKPuw95RBfmxBQZolgeU63a6NjUvGGB6G/ZZuZRe4 Oh9YA3Xx3XfRXW+RPeuZOx9t5hbAa8N724EhUUSC+HacnTho08QqH5COsh5gFkayEJ4m VA08uBeDuNcVu5dsZFSLQODUSNF1ZpYTcxTqAhYAGkGNtHyS2gVT7MiS+33Ma4IyvZx0 npxobrbjWUPKfmQrPZUp84jCMs2bXxs8lGy5OSTGSGydGJ/hnL6aX7bhxaK0gv9rLuBd lORN6cSyj+LggFumt1kjM5zJ87Ut2o9kPTqOVD+v+WwTsxV9SzBi6yxHZDUD+H6Zwdya DvMw== X-Gm-Message-State: AOJu0YxY8R9ejxwtO48ZeHp2V1sSXNZyJNM0+fiteLkKDZ9/kX06/njm q8KbPRQuvgxgG2x0FTU+Eh4cBy2L4A== X-Google-Smtp-Source: AGHT+IGr1w0qw3F7kxqazx8LvpOGQye9waZfDeApENdjX5TDzrAeuVg5Q14ZVN024te9phQXIHT74WOGhg== X-Received: from rmoar-specialist.c.googlers.com ([fda3:e722:ac3:cc00:2b:7d90:c0a8:45d3]) (user=rmoar job=sendgmr) by 2002:a05:6902:f10:b0:dbc:b4dc:fdfc with SMTP id et16-20020a0569020f1000b00dbcb4dcfdfcmr15137ybb.8.1702429346872; Tue, 12 Dec 2023 17:02:26 -0800 (PST) Date: Wed, 13 Dec 2023 01:02:01 +0000 In-Reply-To: <20231213010201.1802507-1-rmoar@google.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20231213010201.1802507-1-rmoar@google.com> X-Mailer: git-send-email 2.43.0.472.g3155946c3a-goog Message-ID: <20231213010201.1802507-6-rmoar@google.com> Subject: [PATCH v4 6/6] Documentation: Add debugfs docs with run after boot From: Rae Moar To: shuah@kernel.org, davidgow@google.com, dlatypov@google.com, brendan.higgins@linux.dev, sadiyakazi@google.com Cc: keescook@chromium.org, arnd@arndb.de, linux-kselftest@vger.kernel.org, linux-arch@vger.kernel.org, kunit-dev@googlegroups.com, linux-kernel@vger.kernel.org, Rae Moar Expand the documentation on the KUnit debugfs filesystem on the run_manual.rst page. Add section describing how to access results using debugfs. Add section describing how to run tests after boot using debugfs. Signed-off-by: Rae Moar --- Changes since v3: - Change the introduction of the debugfs section - Add detail to not being able to run concurrently or run with init data Documentation/dev-tools/kunit/run_manual.rst | 51 ++++++++++++++++++-- 1 file changed, 47 insertions(+), 4 deletions(-) diff --git a/Documentation/dev-tools/kunit/run_manual.rst b/Documentation/dev-tools/kunit/run_manual.rst index e7b46421f247..699d92885075 100644 --- a/Documentation/dev-tools/kunit/run_manual.rst +++ b/Documentation/dev-tools/kunit/run_manual.rst @@ -49,9 +49,52 @@ loaded. The results will appear in TAP format in ``dmesg``. +debugfs +======= + +KUnit can be accessed from userspace via the debugfs filesystem (See more +information about debugfs at Documentation/filesystems/debugfs.rst). + +If ``CONFIG_KUNIT_DEBUGFS`` is enabled, the KUnit debugfs filesystem is +mounted at /sys/kernel/debug/kunit. You can use this filesystem to perform +the following actions. + +Retrieve Test Results +===================== + +You can use debugfs to retrieve KUnit test results. The test results are +accessible from the debugfs filesystem in the following read-only file: + +.. code-block :: bash + + /sys/kernel/debug/kunit//results + +The test results are printed in a KTAP document. Note this document is separate +to the kernel log and thus, may have different test suite numbering. + +Run Tests After Kernel Has Booted +================================= + +You can use the debugfs filesystem to trigger built-in tests to run after +boot. To run the test suite, you can use the following command to write to +the ``/sys/kernel/debug/kunit//run`` file: + +.. code-block :: bash + + echo "any string" > /sys/kernel/debugfs/kunit//run + +As a result, the test suite runs and the results are printed to the kernel +log. + +However, this feature is not available with KUnit suites that use init data, +because init data may have been discarded after the kernel boots. KUnit +suites that use init data should be defined using the +kunit_test_init_section_suites() macro. + +Also, you cannot use this feature to run tests concurrently. Instead a test +will wait to run until other tests have completed or failed. + .. note :: - If ``CONFIG_KUNIT_DEBUGFS`` is enabled, KUnit test results will - be accessible from the ``debugfs`` filesystem (if mounted). - They will be in ``/sys/kernel/debug/kunit//results``, in - TAP format. + For test authors, to use this feature, tests will need to correctly initialise + and/or clean up any data, so the test runs correctly a second time.