From nobody Fri Jun 19 22:36:47 2026 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 893A0C433F5 for ; Mon, 28 Mar 2022 02:48:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237670AbiC1CuR (ORCPT ); Sun, 27 Mar 2022 22:50:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237657AbiC1CuP (ORCPT ); Sun, 27 Mar 2022 22:50:15 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F84027CD8 for ; Sun, 27 Mar 2022 19:48:35 -0700 (PDT) Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4KRcXx0j6xzfZHX; Mon, 28 Mar 2022 10:46:57 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Mon, 28 Mar 2022 10:48:33 +0800 Received: from use12-sp2.huawei.com (10.67.189.20) by dggpemm500007.china.huawei.com (7.185.36.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Mon, 28 Mar 2022 10:48:33 +0800 From: Jubin Zhong To: , CC: , , , , , , Subject: [PATCH v2 RESEND] kbuild: Enable armthumb BCJ filter for Thumb-2 kernel Date: Mon, 28 Mar 2022 10:48:31 +0800 Message-ID: <1648435711-95240-1-git-send-email-zhongjubin@huawei.com> X-Mailer: git-send-email 1.8.5.6 In-Reply-To: <20220326203516.1ddb6492@kaneli> References: <20220326203516.1ddb6492@kaneli> MIME-Version: 1.0 X-Originating-IP: [10.67.189.20] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" xz_wrap.sh use $SRCARCH to detect the BCJ filter. However, assigning arm BCJ filter to Thumb-2 kernel is not optimal. In my case, about 5% decrease of image size is observed with armthumb BCJ filter: Test results: hardware: QEMU emulator version 3.1.0 config: vexpress_defconfig with THUMB2_KERNEL & KERNEL_XZ on arm BCJ: 4029808 armthumb BCJ: 3827280 Choose armthumb BCJ filter for Thumb-2 kernel to make smaller images. Signed-off-by: Jubin Zhong Acked-by: Lasse Collin ---- v1: https://lore.kernel.org/lkml/1637323647-19988-1-git-send-email-zhongjubin@h= uawei.com/ --- lib/decompress_unxz.c | 6 +++++- scripts/xz_wrap.sh | 6 ++++++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/lib/decompress_unxz.c b/lib/decompress_unxz.c index 9f4262e..9d9cb48 100644 --- a/lib/decompress_unxz.c +++ b/lib/decompress_unxz.c @@ -129,7 +129,11 @@ # define XZ_DEC_POWERPC #endif #ifdef CONFIG_ARM -# define XZ_DEC_ARM +# ifdef CONFIG_THUMB2_KERNEL +# define XZ_DEC_ARMTHUMB +# else +# define XZ_DEC_ARM +# endif #endif #ifdef CONFIG_IA64 # define XZ_DEC_IA64 diff --git a/scripts/xz_wrap.sh b/scripts/xz_wrap.sh index 76e9cbc..3824fdf 100755 --- a/scripts/xz_wrap.sh +++ b/scripts/xz_wrap.sh @@ -9,6 +9,8 @@ # You can do whatever you want with this file. # =20 +. include/config/auto.conf + BCJ=3D LZMA2OPTS=3D =20 @@ -20,4 +22,8 @@ case $SRCARCH in sparc) BCJ=3D--sparc ;; esac =20 +if [ -n "${CONFIG_THUMB2_KERNEL}" ]; then + BCJ=3D--armthumb +fi + exec $XZ --check=3Dcrc32 $BCJ --lzma2=3D$LZMA2OPTS,dict=3D32MiB --=20 1.8.5.6