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 C2213CD11C2 for ; Wed, 10 Apr 2024 11:09:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 66B9A11262B; Wed, 10 Apr 2024 11:09:04 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; secure) header.d=linutronix.de header.i=@linutronix.de header.b="hZyAfTue"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="vBgl9VBm"; dkim-atps=neutral Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2680D11262B; Wed, 10 Apr 2024 11:09:01 +0000 (UTC) Date: Wed, 10 Apr 2024 13:08:57 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1712747338; 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: in-reply-to:in-reply-to:references:references; bh=z4akau/w263RG4XtBCzgos4oOxf54v/WcYbiwj1itwE=; b=hZyAfTuewM1PgRpu/coMJ/K+VIhCWWXdNdCd7yAt+HHWuAhdn6jXMpEv8YbxZl65apDb+/ I5Yh+60NFylyUJDT8Wz5OUJzTFXZ+uvz67QOIs1iCrAOVIUQ5VHvjGyi4n4+hJnLp0GU2v CrLuNAy/Ttj+Gbktp7hreHIW2bEmg41eO1VrHHCkO7wR5ZmqTKQPFZBqIttOletyYRIfG+ s35WSRv1ypME5VYxudq7jg3JI9B5zuIAAJ2iGg1h3rYjkbbQiS0cBXgqY89G5e55g8UC1o O3Kph43X8D4PfHc7H/KcP2VrEI4XOTtYxrobKtSlPBfdRa3ZfapiFyJy4fWaDw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1712747338; 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: in-reply-to:in-reply-to:references:references; bh=z4akau/w263RG4XtBCzgos4oOxf54v/WcYbiwj1itwE=; b=vBgl9VBmebm9MuzLiR9PER31trEHxde3zLQJInLVIGJuYoMv4NytP1X8DUEQYwgCih1FNU exdvYNhPfIEHpMBg== From: Sebastian Andrzej Siewior To: Steven Rostedt Cc: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Thomas Gleixner , Tvrtko Ursulin Subject: Re: [PATCH 05/10] drm/i915: skip DRM_I915_LOW_LEVEL_TRACEPOINTS with NOTRACE Message-ID: <20240410110857.BBV2fQYP@linutronix.de> References: <20240405142737.920626-1-bigeasy@linutronix.de> <20240405142737.920626-6-bigeasy@linutronix.de> <20240408130650.6f9c1e1c@rorschach.local.home> <20240409110601.FWFqmGjM@linutronix.de> <20240409115533.7c84b283@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20240409115533.7c84b283@gandalf.local.home> X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On 2024-04-09 11:55:33 [-0400], Steven Rostedt wrote: > I believe you need to do it in the .c file: >=20 > Can you try something like this? >=20 =E2=80=A6 > ? I tried and nothing changed because the lowlevel config option isn't the problem. What about I drop this and replace 4/10 from this series with the patch below? After enabling all tracing I don't see any events in events/i915. Sebastian --------------------->8---------------------------- =46rom: Sebastian Andrzej Siewior Date: Thu, 6 Dec 2018 09:52:20 +0100 Subject: [PATCH] drm/i915: Disable tracing points on PREEMPT_RT Luca Abeni reported this: | BUG: scheduling while atomic: kworker/u8:2/15203/0x00000003 | CPU: 1 PID: 15203 Comm: kworker/u8:2 Not tainted 4.19.1-rt3 #10 | Call Trace: | rt_spin_lock+0x3f/0x50 | gen6_read32+0x45/0x1d0 [i915] | g4x_get_vblank_counter+0x36/0x40 [i915] | trace_event_raw_event_i915_pipe_update_start+0x7d/0xf0 [i915] The tracing events use trace_i915_pipe_update_start() among other events use functions acquire spinlock_t locks which are transformed into sleeping locks on PREEMPT_RT. A few trace points use intel_get_crtc_scanline(), others use ->get_vblank_counter() wich also might acquire a sleeping locks on PREEMPT_RT. At the time the arguments are evaluated within trace point, preemption is disabled and so the locks must not be acquired on PREEMPT_RT. Based on this I don't see any other way than disable trace points on PREMPT_RT. Reported-by: Luca Abeni Cc: Steven Rostedt Signed-off-by: Sebastian Andrzej Siewior --- drivers/gpu/drm/i915/display/intel_display_trace.h | 4 ++++ drivers/gpu/drm/i915/i915_trace.h | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_display_trace.h b/drivers/g= pu/drm/i915/display/intel_display_trace.h index 7862e7cefe027..e4608d855bfba 100644 --- a/drivers/gpu/drm/i915/display/intel_display_trace.h +++ b/drivers/gpu/drm/i915/display/intel_display_trace.h @@ -9,6 +9,10 @@ #if !defined(__INTEL_DISPLAY_TRACE_H__) || defined(TRACE_HEADER_MULTI_READ) #define __INTEL_DISPLAY_TRACE_H__ =20 +#ifdef CONFIG_PREEMPT_RT +#define NOTRACE +#endif + #include #include #include diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_= trace.h index ce1cbee1b39dd..c54653cf72c95 100644 --- a/drivers/gpu/drm/i915/i915_trace.h +++ b/drivers/gpu/drm/i915/i915_trace.h @@ -6,6 +6,10 @@ #if !defined(_I915_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ) #define _I915_TRACE_H_ =20 +#ifdef CONFIG_PREEMPT_RT +#define NOTRACE +#endif + #include #include #include --=20 2.43.0