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 DD288C433F5 for ; Mon, 7 Mar 2022 14:45:50 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7BB1110E146; Mon, 7 Mar 2022 14:45:49 +0000 (UTC) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1F8AC10E13C; Mon, 7 Mar 2022 14:45:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1646664348; x=1678200348; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=KYdedZKsN/8uGL6jG2r23x2DKqGVvfmm8ZNk9lQLr4c=; b=aHP3P0PjjPqwklhnENNdh0drIaGj2q3pxxql9uNCfUUdhc/d5E/zwh8W g1tPLhxfi6QsQbz1nCSdqH/gty/DudfYlXAmilYjPzofwf3MWog6WxEKi kLM2fHISit/5p7eU1192TonjZLv4E9lBQiORAqKlPYh/KrOmMGYeHvNNv ZBkm4R0SYeEQoX1OyGAfHgmURYqvKAc5/3AvuI4j9brVbgsOmqmrx2YBH CpggIkMiLCRmUgEzVqwxfgFjx2c6u13c1gAi+C0L7GZr+6r3OC/+bMkk5 vJkLhvH5EPdzF55rdXy7wpy5DJhWD6nlmUtr6kNmigL/wQTkLDZzVUoDZ w==; X-IronPort-AV: E=McAfee;i="6200,9189,10278"; a="254596046" X-IronPort-AV: E=Sophos;i="5.90,162,1643702400"; d="scan'208";a="254596046" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Mar 2022 06:45:47 -0800 X-IronPort-AV: E=Sophos;i="5.90,162,1643702400"; d="scan'208";a="643270081" Received: from hazimham-mobl.ger.corp.intel.com (HELO localhost) ([10.252.27.252]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Mar 2022 06:45:44 -0800 From: Jani Nikula To: Arunpravin , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Subject: Re: [Intel-gfx] [PATCH] drm: remove min_order BUG_ON check In-Reply-To: <20220307143707.3687-1-Arunpravin.PaneerSelvam@amd.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20220307143707.3687-1-Arunpravin.PaneerSelvam@amd.com> Date: Mon, 07 Mar 2022 16:45:37 +0200 Message-ID: <874k493jou.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: alexander.deucher@amd.com, matthew.auld@intel.com, christian.koenig@amd.com, Arunpravin Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, 07 Mar 2022, Arunpravin wrote: > place BUG_ON(order < min_order) outside do..while > loop as it fails Unigine Heaven benchmark. > > Unigine Heaven has buffer allocation requests for > example required pages are 161 and alignment request > is 128. To allocate the remaining 33 pages, continues > the iteration to find the order value which is 5 and > when it compares with min_order = 7, enables the > BUG_ON(). To avoid this problem, placed the BUG_ON > check outside of do..while loop. How about turning these BUG_ON()s to WARN_ON()s with an error return? What's the point in oopsing? BR, Jani. > > Signed-off-by: Arunpravin > --- > drivers/gpu/drm/drm_buddy.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c > index 72f52f293249..ed94c56b720f 100644 > --- a/drivers/gpu/drm/drm_buddy.c > +++ b/drivers/gpu/drm/drm_buddy.c > @@ -669,10 +669,11 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm, > order = fls(pages) - 1; > min_order = ilog2(min_page_size) - ilog2(mm->chunk_size); > > + BUG_ON(order < min_order); > + > do { > order = min(order, (unsigned int)fls(pages) - 1); > BUG_ON(order > mm->max_order); > - BUG_ON(order < min_order); > > do { > if (flags & DRM_BUDDY_RANGE_ALLOCATION) > > base-commit: 8025c79350b90e5a8029234d433578f12abbae2b -- Jani Nikula, Intel Open Source Graphics Center