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 X-Spam-Level: X-Spam-Status: No, score=-4.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D53AAC433ED for ; Wed, 14 Apr 2021 13:46:38 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 6FC6461164 for ; Wed, 14 Apr 2021 13:46:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6FC6461164 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 149956E7E6; Wed, 14 Apr 2021 13:46:36 +0000 (UTC) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id B99016E7E6 for ; Wed, 14 Apr 2021 13:46:35 +0000 (UTC) IronPort-SDR: m6+vccKHMElqQ2kHleJFA+GzrYAPvGRZRj6vweGswluFpE9hRBgrj3+r1mPlizMyhUU8EYotTG cseFx5hTQNRA== X-IronPort-AV: E=McAfee;i="6200,9189,9954"; a="174139127" X-IronPort-AV: E=Sophos;i="5.82,222,1613462400"; d="scan'208";a="174139127" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2021 06:46:32 -0700 IronPort-SDR: xOXBuiFgwZPtUvoQb+KJtT/F4y4VXHNCT97vcv+yfacKb38ebWHZ9Tc4y9ldX11i3ncV6ToRLo LkB09xygzGNA== X-IronPort-AV: E=Sophos;i="5.82,222,1613462400"; d="scan'208";a="418327228" Received: from bdebhal-mobl.ger.corp.intel.com (HELO [10.213.205.119]) ([10.213.205.119]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2021 06:46:30 -0700 To: Jani Nikula , Lucas De Marchi , intel-gfx@lists.freedesktop.org References: <20210413051002.92589-1-lucas.demarchi@intel.com> <20210413051002.92589-9-lucas.demarchi@intel.com> <2216c8a6-003d-5240-d983-8c162872fd66@linux.intel.com> <87v98pdn60.fsf@intel.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc Message-ID: <319004ad-55cd-3058-3836-cc0bcb26e95c@linux.intel.com> Date: Wed, 14 Apr 2021 14:46:26 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <87v98pdn60.fsf@intel.com> Content-Language: en-US Subject: Re: [Intel-gfx] [PATCH v2 08/12] drm/i915: finish removal of gen_mask 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: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 14/04/2021 14:13, Jani Nikula wrote: > On Wed, 14 Apr 2021, Tvrtko Ursulin wrote: >> On 13/04/2021 06:09, Lucas De Marchi wrote: >>> Now that it's not used anywhere, remove it from struct >>> intel_device_info. To allow a period in which code will be converted to >>> the new macro, keep IS_GEN_RANGE() around, just redefining it to use >>> the new fields. The size advantage from IS_GEN_RANGE() using a mask is >>> not that big as it has pretty limited use througout the driver: >>> >>> text data bss dec hex filename >>> 2758497 95965 6496 2860958 2ba79e drivers/gpu/drm/i915/i915.ko.old >>> 2758586 95953 6496 2861035 2ba7eb drivers/gpu/drm/i915/i915.ko.new >> >> This delta refers to this patch - I mean this point in the series? >> Asking because it may not be 100% representative since some of the >> previous patches have already removed some gen mask usages. >> >> While I am here, I am a bit fond of the mask approach and wonder if >> using it for all (gt/media/whatelse) new fields would still make sense. >> >> Presence of the range check helpers suggests that it might, but I >> haven't looked at how prevalent their usage ends up after the series is >> done. So just in principle, I don't see why not still go with masks >> since that guarantees elegant check at each range check site. It would >> be all hidden in the macro implementation so easy. >> >> Also for historical reference, another reason why I went for masks >> everywhere approach is that at some point we had a feature request to >> allow compiling out platforms/gens. I *think* that was much easier to do >> with masking and in experiments back then I was able for instance to >> build just for Gen9+ and drop like 30% of the binary size. >> >> Oh I found the branch now.. The reason for IS_GEN(p, v) was also in that >> series. I don't know if I ever RFC-ed or trybotted it.. google suggests >> no and I neither can find it in my mailboxes. I could send out the old >> patches for reference? But to be honest I have no idea if this feature >> request (targeted driver builds) will ever resurface.. > > I completely agreed with the direction of using the masks way back when, > especially with the goal of the conditional/targeted compilation. > > I think the question now is whether we want to keep maintaining them > just for the sake of the masks. Keeping them means having three masks > instead of one. And we wouldn't be using most of the benefits with them, > we'd mostly just get the downsides. > > Having the masks per se is not such a big deal, but they're also not > such a big deal to add back later on if needed. It's the codebase all > over that's the hard part. And arguably it's not getting that much > different with the series at hand; the direct uses of INTEL_GEN() and > DISPLAY_VER() vastly outnumber IS_GEN(), IS_GEN_RANGE() and > IS_DISPLAY_RANGE() which could benefit from the mask. > > We'd still be retaining the range macros as IS_GRAPHICS_VER(), > IS_MEDIA_VER() and IS_DISPLAY_VER(), although more for clarity than for > any other reason. Adding masks later would not a big deal, but another cycle of changing "xxx_VER == n" to "IS_xxx_VER(n)" is a churn which could presumably be avoided. It is moot yes, but I don't see a clear case for doing the reversal as part of this series. With a disclaimer that I only glanced over the commit messages today for the first time. So I think from me its neither ack or nack, at least since I don't understand the attractiveness of using the "ver == n" and numerical range check forms everywhere. As said, if we are churning I'd rather go the other direction. But that's a soft objection only so feel free to proceed. Regards, Tvrtko _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx