From patchwork Thu Feb 17 10:34:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Zimmermann X-Patchwork-Id: 543508 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 9DBDBC433EF for ; Thu, 17 Feb 2022 10:34:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234991AbiBQKe1 (ORCPT ); Thu, 17 Feb 2022 05:34:27 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:38724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231827AbiBQKeZ (ORCPT ); Thu, 17 Feb 2022 05:34:25 -0500 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46E1010610D for ; Thu, 17 Feb 2022 02:34:09 -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 E5E3F1F383; Thu, 17 Feb 2022 10:34:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1645094047; 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=F4LK7D/i/q6AMJCHtRDXYS+MysU4b1EGJIuXtJxR1iI=; b=R8Mr+jVBiWde+vWeGGEgGnpmI2luBW5LXkXuBFqDdHXB3IOSryCOJ2DnsG1Pa1CSVYYzfQ +S2z9lY5I5dZza7wFJRd9xb8cRDMqcTxTgTdv/loQOnvywLbvdg7o3X+mpP7BBy6n8OJ4P 6sMEFsBE+icDnWm4bgdbDl94cJbZWzo= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1645094047; 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=F4LK7D/i/q6AMJCHtRDXYS+MysU4b1EGJIuXtJxR1iI=; b=9J04Mw3ixS1TpB/Jj2TD8ZmjsSclYtFzfe1DGti86s3VTFadJIUuvmzCK4x9CYEQtprBuJ h3hTF/MN5hY1ACAg== 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 B903E13DD8; Thu, 17 Feb 2022 10:34:07 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id sBTOK58kDmLQQgAAMHmgww (envelope-from ); Thu, 17 Feb 2022 10:34:07 +0000 From: Thomas Zimmermann To: daniel@ffwll.ch, deller@gmx.de, javierm@redhat.com, geert@linux-m68k.org Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, Thomas Zimmermann Subject: [PATCH 1/2] fbdev: Improve performance of sys_fillrect() Date: Thu, 17 Feb 2022 11:34:04 +0100 Message-Id: <20220217103405.26492-2-tzimmermann@suse.de> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220217103405.26492-1-tzimmermann@suse.de> References: <20220217103405.26492-1-tzimmermann@suse.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org Improve the performance of sys_fillrect() by using word-aligned 32/64-bit mov instructions. While the code tried to implement this, the compiler failed to create fast instructions. The resulting binary instructions were even slower than cfb_fillrect(), which uses the same algorithm, but operates on I/O memory. A microbenchmark measures the average number of CPU cycles for sys_fillrect() after a stabilizing period of a few minutes (i7-4790, FullHD, simpledrm, kernel with debugging). The value for CFB is given as a reference. sys_fillrect(), new: 26586 cycles sys_fillrect(), old: 166603 cycles cfb_fillrect(): 41012 cycles In the optimized case, sys_fillrect() is now ~6x faster than before and ~1.5x faster than the CFB implementation. Signed-off-by: Thomas Zimmermann Reviewed-by: Sam Ravnborg --- drivers/video/fbdev/core/sysfillrect.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/drivers/video/fbdev/core/sysfillrect.c b/drivers/video/fbdev/core/sysfillrect.c index 33ee3d34f9d2..bcdcaeae6538 100644 --- a/drivers/video/fbdev/core/sysfillrect.c +++ b/drivers/video/fbdev/core/sysfillrect.c @@ -50,19 +50,9 @@ bitfill_aligned(struct fb_info *p, unsigned long *dst, int dst_idx, /* Main chunk */ n /= bits; - while (n >= 8) { - *dst++ = pat; - *dst++ = pat; - *dst++ = pat; - *dst++ = pat; - *dst++ = pat; - *dst++ = pat; - *dst++ = pat; - *dst++ = pat; - n -= 8; - } - while (n--) - *dst++ = pat; + memset_l(dst, pat, n); + dst += n; + /* Trailing bits */ if (last) *dst = comp(pat, *dst, last);