From patchwork Mon Feb 21 19:54:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Zimmermann X-Patchwork-Id: 12754094 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C5B48C433FE for ; Mon, 21 Feb 2022 19:54:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233280AbiBUTyn (ORCPT ); Mon, 21 Feb 2022 14:54:43 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:35680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230327AbiBUTyi (ORCPT ); Mon, 21 Feb 2022 14:54:38 -0500 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B686A22535 for ; Mon, 21 Feb 2022 11:54:14 -0800 (PST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 62AE41F393; Mon, 21 Feb 2022 19:54:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1645473253; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=q745Q564KmJVNw2+KNdAukT4aGfTFfnZ3w3mvLB/yBI=; b=UnbayNe9KQbm/poEukp9x5SViT3pPlKxY0ogOxVGl8qIrIpeo1x9ufInDe10xfvvo74vne YMHHnlWJnOQAwGngW36sJTkLhGtMMU4EgHaq8gIeik4SbZ+dHEf54elpdoUhxOI4dPeiTC 1EaDXP0dgpFlC6eN0mI293iSmDNbrP4= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1645473253; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=q745Q564KmJVNw2+KNdAukT4aGfTFfnZ3w3mvLB/yBI=; b=FeKuXRzQ/pJVq4U81QMByWL9fordS+ipoXTH9aslkKeo+lKfyleBD7c4oc76U0zuYNJocT q6sGglrciQAr+WBA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 2D99313B78; Mon, 21 Feb 2022 19:54:13 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id iFAiCuXtE2KVPwAAMHmgww (envelope-from ); Mon, 21 Feb 2022 19:54:13 +0000 From: Thomas Zimmermann To: daniel@ffwll.ch, deller@gmx.de, javierm@redhat.com, geert@linux-m68k.org, sam@ravnborg.org, kraxel@redhat.com Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, Thomas Zimmermann Subject: [PATCH v2 5/5] drm: Add TODO item for optimizing format helpers Date: Mon, 21 Feb 2022 20:54:10 +0100 Message-Id: <20220221195410.9172-6-tzimmermann@suse.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220221195410.9172-1-tzimmermann@suse.de> References: <20220221195410.9172-1-tzimmermann@suse.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org Add a TODO item for optimizing blitting and format-conversion helpers in DRM and fbdev. There's always demand for faster graphics output. Signed-off-by: Thomas Zimmermann --- Documentation/gpu/todo.rst | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 7bf7f2111696..7f113c6a02dd 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -241,6 +241,28 @@ Contact: Thomas Zimmermann , Daniel Vetter Level: Advanced +Benchmark and optimize blitting and format-conversion function +-------------------------------------------------------------- + +Drawing to dispay memory quickly is crucial for many applications' +performance. + +On at least x86-64, sys_imageblit() is significantly slower than +cfb_imageblit(), even though both use the same blitting algorithm and +the latter is written for I/O memory. It turns out that cfb_imageblit() +uses movl instructions, while sys_imageblit apparently does not. This +seems to be a problem with gcc's optimizer. DRM's format-conversion +heleprs might be subject to similar issues. + +Benchmark and optimize fbdev's sys_() helpers and DRM's format-conversion +helpers. In cases that can be further optimized, maybe implement a different +algorithm, For micro-optimizations, use movl/movq instructions explicitly. +That might possibly require architecture specific helpers (e.g., storel() +storeq()). + +Contact: Thomas Zimmermann + +Level: Intermediate drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup -----------------------------------------------------------------