From patchwork Mon Jul 22 21:06:41 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas De Marchi X-Patchwork-Id: 13739100 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 8C726C3DA64 for ; Mon, 22 Jul 2024 21:07:06 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B33A610E31B; Mon, 22 Jul 2024 21:07:04 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="Eaguog1t"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.13]) by gabe.freedesktop.org (Postfix) with ESMTPS id B78DC10E31A; Mon, 22 Jul 2024 21:07:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1721682420; x=1753218420; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=cLNPe9dx4bBLrxya/4PwK4euVFfE/6NBva4Wj7GDAqc=; b=Eaguog1tN7fl8n/EN58cvKRU/ESB6g6O4wDZfuVv3wBpsiK1RPCoDciO U2E13vrLAsy65ZuaUCf94B/TUrJxIXYmLOaumLexMwAKViHgfkLgiDVjj z578V4aQAXJ8EPctc41TKsPwiAAk/4CEFuNOjeEtnTt+pwLtsGJuf7w80 +GzbyKVbkL/WWlB7nfRE1g8LgQUbjK61ORKBClcUXEViqPRyD4YYg+Qte tgJhiaxevUP96CBgVqTbsRVmkfQ58HfH2cFXBaPISTFETor4WPsY9mMK6 GijY4Cm8BQ8WLF6TXBKDWacX9JVCueuE7d70MY0yPwErHjyBFw0KNmkEZ Q==; X-CSE-ConnectionGUID: NpCj4XCuQw280wCYp03KoA== X-CSE-MsgGUID: utcUgPHVRD2YUPf1mhdHKQ== X-IronPort-AV: E=McAfee;i="6700,10204,11141"; a="30428287" X-IronPort-AV: E=Sophos;i="6.09,229,1716274800"; d="scan'208";a="30428287" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jul 2024 14:07:00 -0700 X-CSE-ConnectionGUID: ZHmecsDgS3euI2nR5IUSvg== X-CSE-MsgGUID: OAAxfdpqQkmvkBkUg97pwg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.09,229,1716274800"; d="scan'208";a="51653263" Received: from lucas-s2600cw.jf.intel.com ([10.165.21.196]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jul 2024 14:06:59 -0700 From: Lucas De Marchi To: intel-gfx@lists.freedesktop.org, linux-perf-users@vger.kernel.org Cc: Tvrtko Ursulin , dri-devel@lists.freedesktop.org, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, Lucas De Marchi Subject: [PATCH 0/7] Fix i915 pmu on bind/unbind Date: Mon, 22 Jul 2024 14:06:41 -0700 Message-ID: <20240722210648.80892-1-lucas.demarchi@intel.com> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" This is intended to fix the pmu integration in i915 when the device unbinds. I don't have the hardware to test, but I belive a similar issue occurs with any driver using perf_pmu_unregister() if they can unbind from the device - in drm subsystem, that would be the amd driver. Previous attempts I could find: 1) https://lore.kernel.org/lkml/20240115170120.662220-1-tvrtko.ursulin@linux.intel.com/ 2) https://lore.kernel.org/all/20240213180302.47266-1-umesh.nerlige.ramappa@intel.com/ I think (2) is a no-go as it tries to do everything from the i915 side by force-closing the fd. I believe this series is simpler* than (1), but that could could also be a good alternative if we want to go with that approach. First patch is to perf. The rest is to i915 that builds on that and moves the unregister bit by bit to be done later, after the last reference to i915 is dropped. Peter/Ingo, could I get your opinion on this or if (1) would be a good alternative? Thanks. * simpler, but see downside mentioned in patch 6 Lucas De Marchi (7): perf/core: Add pmu get/put drm/i915/pmu: Fix crash due to use-after-free drm/i915/pmu: Use event_to_pmu() drm/i915/pmu: Drop is_igp() drm/i915/pmu: Let resource survive unbind drm/i915/pmu: Lazy unregister drm/i915/pmu: Do not set event_init to NULL drivers/gpu/drm/i915/i915_pmu.c | 103 ++++++++++++++++---------------- include/linux/perf_event.h | 3 + kernel/events/core.c | 32 ++++++++-- 3 files changed, 81 insertions(+), 57 deletions(-)