From patchwork Fri Jun 28 12:57:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 13716095 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 C680FC30658 for ; Fri, 28 Jun 2024 13:06:09 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1EF6710E0EE; Fri, 28 Jun 2024 13:06:09 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; secure) header.d=linutronix.de header.i=@linutronix.de header.b="LtIn4lJ0"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="549x4V07"; dkim-atps=neutral Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1198410E0EE; Fri, 28 Jun 2024 13:06:08 +0000 (UTC) From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1719579966; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=t2PWw8MLm+wjqtXPAY7SGj8voS96oKHhcy6AwpKo7W4=; b=LtIn4lJ0ofrurDpY1J6etY31vKU0obLKYgPoqVr0DPHIJrkWArqxIN5MhAaQR/i16gpCDl 1aJ7PmxamTvSFegKFtT2U7SZ7c5xce1BTB2H2bM5JdeBmuAHoAVpk5lUDvqZ1TYKj3IAJ9 ugcdZOYeq1VWFmKvL9R0KvzIyrZFV4QbBp2bCXu3hBRy/Mm9SMKk1FfWXYsDqvSV4H4ZC/ 0OTvPTYl5hBPIB2YcV5MVVacp29xWe6X7BkmDuEcTlfhEFB61meu2O22iiG3xEodh6JfDP kEnF0mYILMFjf5zxrTiea6RXHaeoQUEXgxCcfEdKO7s50F/IBrXgLqj+o0/BKw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1719579966; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=t2PWw8MLm+wjqtXPAY7SGj8voS96oKHhcy6AwpKo7W4=; b=549x4V07YJ2UzC3xmfXJc+i6PNDsk/W951YloPu6z3HnMIZP/YBaPQl1bdYbf8TaL27bVr Gwp5wqo9kCIfuGCA== To: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Cc: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Thomas Gleixner , Tvrtko Ursulin Subject: [PATCH v3 0/8] drm/i915: PREEMPT_RT related fixups. Date: Fri, 28 Jun 2024 14:57:59 +0200 Message-ID: <20240628130601.1772849-1-bigeasy@linutronix.de> 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" Hi, The following patches are from the PREEMPT_RT queue. It is mostly about disabling interrupts/preemption which leads to problems. Unfortunately DRM_I915_LOW_LEVEL_TRACEPOINTS had to be disabled because it acquires locks from within trace points. Making the lock a raw_spinlock_t led to higher latencies during video playback https://lore.kernel.org/all/20211006164628.s2mtsdd2jdbfyf7g@linutronix.de/ and I'm not sure if I hit the worse case here. I tested it on a SandyBridge with built-in i915 by using X, OpenGL and playing videos without noticing any warnings. However, some code paths were not entered. I carry them for some time now and most issues were reported by other people and they reported that things work for them since. v2…v3 https://lore.kernel.org/all/20240613102818.4056866-1-bigeasy@linutronix.de/ - Collected tags. - Added comment to 3/8 explaining why RT is excluded from the test. v1…v2: - The tracing disable bits (4/8) have been reworked after Steven pointed out that something isn't right. - The irq_work() bits have been dropped because they are no longer needed. Sebastian