From patchwork Fri Aug 11 21:51:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhangjin Wu X-Patchwork-Id: 712990 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 BC2A8C0015E for ; Fri, 11 Aug 2023 21:52:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236570AbjHKVwO (ORCPT ); Fri, 11 Aug 2023 17:52:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235401AbjHKVwO (ORCPT ); Fri, 11 Aug 2023 17:52:14 -0400 Received: from bg4.exmail.qq.com (bg4.exmail.qq.com [43.155.65.254]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E957271B; Fri, 11 Aug 2023 14:52:10 -0700 (PDT) X-QQ-mid: bizesmtp69t1691790715t2l3imm8 Received: from linux-lab-host.localdomain ( [116.30.128.116]) by bizesmtp.qq.com (ESMTP) with id ; Sat, 12 Aug 2023 05:51:53 +0800 (CST) X-QQ-SSF: 01200000000000E0X000000A0000000 X-QQ-FEAT: jGGC4gWX7WFEuWrQD10QYevA6rKFR5eyLN27zADU7mMJyUa1X6F5wj5b8c1PO ER8oXLqoaZcj68vp2XW1IvvzWMXYjLid4rTDbWxcHY9+xK0LZ6TboYz9xrN1UuKrfZPeivH Xhx+frlWCSJTPIl4qTvNiv+IIPg62gxZBtdjgSzG1OWsfAsHQZwMgx7V1TgW3uPw9evoaY9 f/3qSx8aKzolxDdGprJ9lCbNnqC8BdKQhSeoDf1ZVL0vz1omtIq9sC7KeFcpXHcLENpcFN+ ZEMfFnvLJZED4528TgM/+SpuC2OxOWzKeNxwVnytS785YBa97JXf5RSeKCPgFQkYpErIUmN JyXdyk2gkVM2i9Ad6ukNE5KRQK4tVquu5jqDZvRRUNb6m1LNpMtGj4GfqQLSUQA0SHWLMTn X-QQ-GoodBg: 0 X-BIZMAIL-ID: 14313426769615256479 From: Zhangjin Wu To: w@1wt.eu Cc: falcon@tinylab.org, david.laight@aculab.com, arnd@arndb.de, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, tanyuan@tinylab.org, thomas@t-8ch.de Subject: [PATCH v6 2/2] tools/nolibc: fix up size inflate regression Date: Sat, 12 Aug 2023 05:51:53 +0800 Message-Id: <96624cc918092737d35dd539d184de06dba7a9b8.1691788036.git.falcon@tinylab.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:tinylab.org:qybglogicsvrgz:qybglogicsvrgz5a-1 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org As reported and suggested by Willy, the inline __sysret() helper introduces three types of conversions and increases the size: (1) the "unsigned long" argument to __sysret() forces a sign extension from all sys_* functions that used to return 'int' (2) the comparison with the error range now has to be performed on a 'unsigned long' instead of an 'int' (3) the return value from __sysret() is a 'long' (note, a signed long) which then has to be turned back to an 'int' before being returned by the caller to satisfy the caller's prototype. To fix up this, firstly, let's use macro instead of inline function to preserves the input type and avoids these useless conversions (1), (3). Secondly, since all of the sys_* functions have been converted to return integer, now, it is able to remove comparison to a 'unsigned long' -MAX_ERRNO (2) and restore the simple sign comparison as before. Suggested-by: Willy Tarreau Link: https://lore.kernel.org/lkml/20230806095846.GB10627@1wt.eu/ Signed-off-by: Zhangjin Wu --- tools/include/nolibc/sys.h | 27 ++++++++++----------------- 1 file changed, 10 insertions(+), 17 deletions(-) diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index a28e7fbff448..e0b68d3532b6 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -27,23 +27,16 @@ #include "errno.h" #include "types.h" - -/* Syscall return helper for library routines, set errno as -ret when ret is in - * range of [-MAX_ERRNO, -1] - * - * Note, No official reference states the errno range here aligns with musl - * (src/internal/syscall_ret.c) and glibc (sysdeps/unix/sysv/linux/sysdep.h) - */ - -static __inline__ __attribute__((unused, always_inline)) -long __sysret(unsigned long ret) -{ - if (ret >= (unsigned long)-MAX_ERRNO) { - SET_ERRNO(-(long)ret); - return -1; - } - return ret; -} +/* Syscall return helper, set errno as -ret when ret < 0 */ +#define __sysret(arg) \ +({ \ + __typeof__(arg) __ret = (arg); \ + if (__ret < 0) { \ + SET_ERRNO(-__ret); \ + __ret = -1L; \ + } \ + __ret; \ +}) /* Functions in this file only describe syscalls. They're declared static so * that the compiler usually decides to inline them while still being allowed