From patchwork Wed Jul 10 13:01:53 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 168800 Delivered-To: patch@linaro.org Received: by 2002:a92:4782:0:0:0:0:0 with SMTP id e2csp9937464ilk; Wed, 10 Jul 2019 06:02:49 -0700 (PDT) X-Google-Smtp-Source: APXvYqwBpTAyXSD0pu25LywFaT+iM6qeJAPFrS2WAzAmhoqqQ7Re7jdHCUB7fmMAoP+yKsaRXhNN X-Received: by 2002:a63:500e:: with SMTP id e14mr37519001pgb.11.1562763768848; Wed, 10 Jul 2019 06:02:48 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1562763768; cv=none; d=google.com; s=arc-20160816; b=DbwYTKGoyzykjzcmlXLx0FcCYTXMmwTkKgc6QK84fbtZAkd5jwIemgJstQsieliDSo J3vGO77BNeFsl0/DE8BBHSsp3BB8RGud66gcekJPn8FSrEYUOr+onp4yQCV0L0NR/28b wnL3dRuJRevSkiFfddPmCKYz+EqvMarMjHQQbexiEV3Nlhqr7gnmwnNwxnecWtdrWnJT zzq3g27O6rOso9POnmTnpwjmwFKue1p9GO2x0RKHm7QlgUxHzaOCltRguRBoqMDKlE03 +5ptRWp4LPEwkHfWZjXiuCrU3WsdKLzCC4KdNwZ905sUj5k+kHqdnc+uiBD2ShQGJyXI ob1A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from; bh=3qsmrnnqcK4GW6U1nqWiNhtp/Go1DzXmb5MLQuKXavs=; b=Ctx8NC4+Cq7Or6BPuHDfmeW4L8/f4E+fJQL6Ag4ENgTvZjS3mS10MF2uBxLhdcJU0k WhAfoVIAqmA81Q0/VMTPuxl4Dm/AxhJvBoOy+p9Z+AvhIzIGXjA9Zrsr2JEVX+VUT+b8 yQjk78a1u7XsehTapuV9q7i+UPjcFPJz6zJWWsOfuGXNVJvlFNOmdXpNMDsDOkwoH571 jxlACRGAI2mI87sEZL0sBDfGtV6nFKwSHAib05vjVcic/fm6XRM/ucH7WyFyqL/b1+Fr UNOHT8HGSclA3yUWFPRUoDVVIU74houozqZYq4TJOfOz2eL4XUQ++dMLSTLl+Mz1cABS PHUw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id v15si2184889pfm.238.2019.07.10.06.02.48; Wed, 10 Jul 2019 06:02:48 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727221AbfGJNCr (ORCPT + 30 others); Wed, 10 Jul 2019 09:02:47 -0400 Received: from mout.kundenserver.de ([212.227.17.24]:39281 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726080AbfGJNCq (ORCPT ); Wed, 10 Jul 2019 09:02:46 -0400 Received: from threadripper.lan ([149.172.19.189]) by mrelayeu.kundenserver.de (mreue106 [212.227.15.145]) with ESMTPA (Nemesis) id 1MfqGN-1iQbak3EYz-00gD3I; Wed, 10 Jul 2019 15:02:11 +0200 From: Arnd Bergmann To: Andy Lutomirski , Thomas Gleixner , Vincenzo Frascino Cc: Arnd Bergmann , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-kselftest@vger.kernel.org, Catalin Marinas , Will Deacon , Russell King , Ralf Baechle , Paul Burton , Daniel Lezcano , Mark Salyzyn , Peter Collingbourne , Shuah Khan , Dmitry Safonov <0x7f454c46@gmail.com>, Rasmus Villemoes , Huw Davies , linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com Subject: [PATCH] vsyscall: use __iter_div_u64_rem() Date: Wed, 10 Jul 2019 15:01:53 +0200 Message-Id: <20190710130206.1670830-1-arnd@arndb.de> X-Mailer: git-send-email 2.20.0 MIME-Version: 1.0 X-Provags-ID: V03:K1:VYafebV/Q7CLTnWZ3vcfCq05iJn/NVcnt1G0HsD21yoEzIkoekE GowoTPqBzup5f7V7xMLaEhy9kYVbaCnEXVORNGnVIa8I2H78SDiMxn8HQmhjaxAcq4M75O3 n1F8e1rj/DWTM3EUk68i9Xc0Ao0x514ZBgN+xP1ILeAPJqVS+IE7IlGj8Aqn56bIoG9A/Xg UepIr9PkVYqdrblAse6ww== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1; V03:K0:JDc5rbPPiV4=:XAvQ8JJ5XLRK8GSkrUMuz/ HWUwAcw/PhALur/u6/ttxc3cm9gdCqtsTNP52XyBncxE2HOTgoKvR3otYj/sts/ORoquxdGsz BxR0NKAzNwmYughjAVvXKClqjgD9SEX8zpODX2NZzeOWv5JayFghv5E6qGgaoqyGUzUp2zsL3 AFfZQWAAKs9U8Doq+EnhblZnFZbJYXw8DnzdtvE0+a0EI+0oJvQPPU6CQqkYAjNkYiDj8QDQX GPT2vGHj479BaPHnNRIyBq+aXw6GOQ70W/+rZFZqFpbNf7bjKtYCMBl6OTswrpqXDQp+/coNl BZopxI79m2Xxes8/GmUJYF4p8qmEYfePM39/G1O/ErJ5kzOaAOjI8gw4OiuEwN1z53/Fu09dN nH48rqsKfJVRCo3Fh0FlcWNbVVn23+3YoQOKj8/hkTeZD7tbcwbAEEniEIIFFeKeY6ZHmFkmm UGmKiaWSa2GilVF0BbvBv/m3EQ9PF61lukpTnI2cpAaXzUdFAOciz6he839Bk8PRkm/Gg4LgQ fL+LlDYge+e1k0KnTuY/I5ckYX8WuOZHZtN87AgdBPO9qsV8jeh6AjhErOfyeMSU0hUhP0KuZ DJ4x+nwBH3akGdENlotFLEuh8ogcq2IIk+eB9ge4Krbd/CjIhHt2VKGP7uZEuQR1Qv0qwqMTP kkZ6QFe/kMFjoAGKoKyw75KK4IjiMwWixw0j5uI706+1CfzNH3T3rEvOMoYcU4flZYNW+Ztej tMj9T/hBrnPCeLPBBi8Mb8K0S8H8UPmwftlyZA== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 32-bit x86 when building with clang-9, the loop gets turned back into an inefficient division that causes a link error: kernel/time/vsyscall.o: In function `update_vsyscall': vsyscall.c:(.text+0xe3): undefined reference to `__udivdi3' Use the provided __iter_div_u64_rem() function that is meant to address the same case in other files. Fixes: 44f57d788e7d ("timekeeping: Provide a generic update_vsyscall() implementation") Signed-off-by: Arnd Bergmann --- kernel/time/vsyscall.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) -- 2.20.0 Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Signed-off-by: Arnd Bergmann diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c index a80893180826..8cf3596a4ce6 100644 --- a/kernel/time/vsyscall.c +++ b/kernel/time/vsyscall.c @@ -104,11 +104,7 @@ void update_vsyscall(struct timekeeper *tk) vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec; nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift; nsec = nsec + tk->wall_to_monotonic.tv_nsec; - while (nsec >= NSEC_PER_SEC) { - nsec = nsec - NSEC_PER_SEC; - vdso_ts->sec++; - } - vdso_ts->nsec = nsec; + vdso_ts->sec += __iter_div_u64_rem(nsec, NSEC_PER_SEC, &vdso_ts->nsec); if (__arch_use_vsyscall(vdata)) update_vdso_data(vdata, tk);