From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 211D3C02193 for ; Tue, 28 Jan 2025 15:16:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D20EA10E689; Tue, 28 Jan 2025 15:16:41 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="P96j3VPC"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.18]) by gabe.freedesktop.org (Postfix) with ESMTPS id 75DBB10E684 for ; Tue, 28 Jan 2025 15:16:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1738077400; x=1769613400; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=qU0FWNVJtFjQ3p0jhufg3iySW0t1vlHVliwFTFJ0cbI=; b=P96j3VPC7paqtpBgj8zl8uJd6S5PoN1AUEjZI87PaP/tZVyFmYwqY/30 q7751rPqGO9ikGbLnOkw/ynwHSq7SwHApyAmCddTWug5mLugN/5ZKglov UIiHdHbZT5d6rsVpEZc2GaKq/6+igaHLimoWKxtfOKvbovJ0hV4WR7Vn4 lLRGzhxl0VnBPJ7B1S1gu963o54BhsPStAh0HmHoBkBhJE2YMz/KtakZ6 iX8Yf4OIoNvEOHSupp1UrYwHxGXioUuQpeVVTaeeYAK2VRzKS06xJZPoc h52+1xTKYV9lRGXeJPq5C8ORQABFbXmbIwkfq32QFUhZBocjQCsV74dHB w==; X-CSE-ConnectionGUID: O9al4heOSZW6tpvJQ+5/nw== X-CSE-MsgGUID: 0W5J4KiaTt2YtbaWUOOlCw== X-IronPort-AV: E=McAfee;i="6700,10204,11314"; a="38667832" X-IronPort-AV: E=Sophos;i="6.12,310,1728975600"; d="scan'208";a="38667832" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by orvoesa110.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jan 2025 07:16:37 -0800 X-CSE-ConnectionGUID: i3z27F7nSIGXcvXRZIg6Zg== X-CSE-MsgGUID: uH7hzWPfS5iz+WWa3aAKiw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.13,241,1732608000"; d="scan'208";a="113763892" Received: from hpabst-mobl.ger.corp.intel.com (HELO friendship7-home.clients.intel.com) ([10.246.21.97]) by fmviesa004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jan 2025 07:16:35 -0800 From: Peter Senna Tschudin To: igt-dev@lists.freedesktop.org Cc: Peter Senna Tschudin , ryszard.knop@intel.com, lucas.demarchi@intel.com, katarzyna.piecielska@intel.com, jonathan.cavitt@intel.com Subject: [PATCH i-g-t v4 0/2] Integrate kmemleak scans in igt_runner Date: Tue, 28 Jan 2025 16:15:35 +0100 Message-Id: <20250128151537.515639-1-peter.senna@linux.intel.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: igt-dev@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development mailing list for IGT GPU Tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: igt-dev-bounces@lists.freedesktop.org Sender: "igt-dev" This patch series introduces a library to interact with the Linux kernel's kmemleak feature and integrates it into igt_runner. If kmemleaks are detected, they will be saved in the igt_runner results directory in a file named kmemleak.txt. During testing, the size of the kmemleak.txt file varied significantly. Larger files, up to 2 MB, were observed when running i915-BAT on a Tiger Lake DUT. Conversely, smaller files, typically under 100 KB, were generated when running Xe BAT on the same DUT. Large files often contain numerous false positives, with the e1000 driver being a frequent source of noise. The time required for the Linux kernel to complete a kmemleak scan ranges from 5 to 60 seconds. This variability can cause igt_runner to slow down by a factor of 4 when using the -keach option. Transient leaks are a common phenomenon but are mostly undetected by the current version of this library. A typical transient leak occurs when pointers are reused, such as in linked lists. For example, if 10 calls to kmalloc are made, storing the address in the same variable and freeing only the final allocation, the previous 9 allocations become transient leaks. These leaks will go undetected unless the kernel thread performs continuous scanning. To enable continuous scanning: # echo scan=1 > /sys/kernel/debug/kmemleak This configures the kmemleak kernel thread to scan the memory continuously with 1 second pauses. While this may increase the likelihood of detecting transient leaks, it can significantly impact system performance. In most cases, the igt_runner slowdown remains in the 4x range, but the kernel thread will consume 100% of a CPU core, as observed with tools like top. When using scan=1, transient leaks that exist during an active scan will be detected. However, detection remains non-deterministic due to timing. It is recommended to reset the scan interval to the default value of 600 seconds after completing your tests. v4: - Cleaned-up CC list - Fixed typo in patch numbering - Fixed Reviewed-by tag - Reintroduced ',' after "results-path". It was removed by accident - Changed unit testing for calling igt_kmemleak() with and without sync. v3: - Removed '>' from the end of one of the email addresses in the cc list - Removed email addresses that no longer exist v2: - Pass igt_kmemleak_sync as a function variable to igt_kmemleak instead of keeping it stored as a global variable - igt_kmemleak_found_leaks(): Remove call to fseek() after close() - igt_kmemleak_write(): Increase retry counter when writing 0 bytes - igt_kmemleak_write(): change type to bool - Unit Testing: Move the call to igt_kmemleak_init() to a fixture. - igt_kmemleak_append_to(): Add brackets to the if statement for improved readability CC: ryszard.knop@intel.com CC: lucas.demarchi@intel.com CC: katarzyna.piecielska@intel.com CC: jonathan.cavitt@intel.com Peter Senna Tschudin (2): lib/igt_kmemleak: library to interact with kmemleak runner/executor: Integrate igt_kmemleak scans lib/igt_kmemleak.c | 274 +++++++++++++++++++++++++++++++++++++++ lib/igt_kmemleak.h | 16 +++ lib/meson.build | 1 + lib/tests/igt_kmemleak.c | 267 ++++++++++++++++++++++++++++++++++++++ lib/tests/meson.build | 1 + runner/executor.c | 25 +++- runner/runner_tests.c | 16 ++- runner/settings.c | 31 ++++- runner/settings.h | 2 + 9 files changed, 629 insertions(+), 4 deletions(-) create mode 100644 lib/igt_kmemleak.c create mode 100644 lib/igt_kmemleak.h create mode 100644 lib/tests/igt_kmemleak.c -- 2.34.1