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 88E6ECE8349 for ; Mon, 30 Sep 2024 13:55:01 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2E5CD10E504; Mon, 30 Sep 2024 13:55:01 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="nrt2KZaH"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) by gabe.freedesktop.org (Postfix) with ESMTPS id E85E510E3F6; Mon, 30 Sep 2024 13:54:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1727704500; x=1759240500; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=lU9Iw+9fXhpwvJ4aYxm37TuLZEitmM+DZgzjVdKPIuc=; b=nrt2KZaHVXOnozIHsw35bwiV7TBfeVlfQHWYbHNBORqBJvAjXIj1onA7 gTZufm8JoAgvkVr7JjBhVyzcsYMDMLVvsFF1IKdT9TmLUSPfhdCLlSAFF ljqR2eMVu+pYWF1SPICf66WiHnyi0ovcRJrmdkAVJCtRL7rs5lvezSmvQ nJ9bqcqqrSvsKEu7gQdjjmMsTaHKZ/Obiv1sWOgUM3gqCX9/JWYHenL24 o0/ujb8qxGjDeOO5lrO5Q1ZErwHfH2HgrkEvQcqVFM/1U9mWkbSe1ngV/ IrWRNHRBO2lMwpk0PjaqhcvfVxDdOz56BsxuAXZYGfcTJ7vzRLALR0W4L g==; X-CSE-ConnectionGUID: 3438XEd7QdCzzO/n4Evmbg== X-CSE-MsgGUID: HAHWyqRnTCyA4qGrzVFnWw== X-IronPort-AV: E=McAfee;i="6700,10204,11211"; a="44254172" X-IronPort-AV: E=Sophos;i="6.11,165,1725346800"; d="scan'208";a="44254172" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Sep 2024 06:54:59 -0700 X-CSE-ConnectionGUID: DR3IS1+qQaSdtk7Z9NGX/g== X-CSE-MsgGUID: IN5vmG/KS8CmYG8id1p+tg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,165,1725346800"; d="scan'208";a="73361272" Received: from sschumil-mobl2.ger.corp.intel.com (HELO localhost) ([10.245.246.136]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Sep 2024 06:54:56 -0700 From: Jani Nikula To: Rodrigo Vivi Cc: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, Matthew Auld , Anshuman Gupta , Andi Shyti , Nathan Chancellor , stable@vger.kernel.org Subject: Re: [PATCH v2 1/6] drm/i915/gem: fix bitwise and logical AND mixup In-Reply-To: <87r095ze2i.fsf@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <643cc0a4d12f47fd8403d42581e83b1e9c4543c7.1726680898.git.jani.nikula@intel.com> <87r095ze2i.fsf@intel.com> Date: Mon, 30 Sep 2024 16:54:43 +0300 Message-ID: <87wmitw8kc.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain 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" On Fri, 27 Sep 2024, Jani Nikula wrote: > On Thu, 26 Sep 2024, Rodrigo Vivi wrote: >> On Wed, Sep 18, 2024 at 08:35:43PM +0300, Jani Nikula wrote: >>> CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND is an int, defaulting to 250. When >>> the wakeref is non-zero, it's either -1 or a dynamically allocated >>> pointer, depending on CONFIG_DRM_I915_DEBUG_RUNTIME_PM. It's likely that >>> the code works by coincidence with the bitwise AND, but with >>> CONFIG_DRM_I915_DEBUG_RUNTIME_PM=y, there's the off chance that the >>> condition evaluates to false, and intel_wakeref_auto() doesn't get >>> called. Switch to the intended logical AND. >>> >>> v2: Use != to avoid clang -Wconstant-logical-operand (Nathan) >> >> oh, this is ugly! >> >> Wouldn't it be better then to use IS_ENABLED() macro? > > It's an int config option, not a bool. (Yes, the name is misleading.) > > IS_ENABLED(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND) would be the same as > CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND == 1. > > We're actually checking if the int value != 0, so IMO the patch at hand > is fine. Ping, r-b on this one too? BR, Jani. > > BR, > Jani. > > >> >>> >>> Fixes: ad74457a6b5a ("drm/i915/dgfx: Release mmap on rpm suspend") >>> Cc: Matthew Auld >>> Cc: Rodrigo Vivi >>> Cc: Anshuman Gupta >>> Cc: Andi Shyti >>> Cc: Nathan Chancellor >>> Cc: # v6.1+ >>> Reviewed-by: Matthew Auld # v1 >>> Reviewed-by: Andi Shyti # v1 >>> Signed-off-by: Jani Nikula >>> --- >>> drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c >>> index 5c72462d1f57..b22e2019768f 100644 >>> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c >>> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c >>> @@ -1131,7 +1131,7 @@ static vm_fault_t vm_fault_ttm(struct vm_fault *vmf) >>> GEM_WARN_ON(!i915_ttm_cpu_maps_iomem(bo->resource)); >>> } >>> >>> - if (wakeref & CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND) >>> + if (wakeref && CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND != 0) >>> intel_wakeref_auto(&to_i915(obj->base.dev)->runtime_pm.userfault_wakeref, >>> msecs_to_jiffies_timeout(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND)); >>> >>> -- >>> 2.39.2 >>> -- Jani Nikula, Intel