From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BE95C54E4B for ; Tue, 12 May 2020 06:42:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5190320733 for ; Tue, 12 May 2020 06:42:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5190320733 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E559D900097; Tue, 12 May 2020 02:42:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E06C0900036; Tue, 12 May 2020 02:42:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D1CE7900097; Tue, 12 May 2020 02:42:47 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0062.hostedemail.com [216.40.44.62]) by kanga.kvack.org (Postfix) with ESMTP id B7C7A900036 for ; Tue, 12 May 2020 02:42:47 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 663D4485A for ; Tue, 12 May 2020 06:42:47 +0000 (UTC) X-FDA: 76807123974.07.flame96_6f703307fcc59 X-HE-Tag: flame96_6f703307fcc59 X-Filterd-Recvd-Size: 2398 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by imf20.hostedemail.com (Postfix) with ESMTP for ; Tue, 12 May 2020 06:42:45 +0000 (UTC) IronPort-SDR: t+uBPzFdl5XsLnCRgbSjIkwxckM0YwoK8+ggeE5L5Qu5VnvNVnnyPRBl/EVFrP3vgbOhXK9oeh kq/Vnlky3+Jg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 May 2020 23:42:44 -0700 IronPort-SDR: 1tiEiWhxupsymV5zFEjn4Lx/KOB/N5fKsP5Dv6VPZaVYK01KcefeemHtX/AAofvKteE/wX5Igv fGBE7U9tTxrw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,382,1583222400"; d="scan'208";a="371468310" Received: from liming1-mobl1.ccr.corp.intel.com (HELO yhuang-mobile.ccr.corp.intel.com) ([10.254.212.233]) by fmsmga001.fm.intel.com with ESMTP; 11 May 2020 23:42:42 -0700 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Michal Hocko , Minchan Kim , Tim Chen , Hugh Dickins Subject: [PATCH] mm, swap: Use prandom_u32_max() Date: Tue, 12 May 2020 14:41:46 +0800 Message-Id: <20200512064147.514493-1-ying.huang@intel.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: To improve the code readability and get random number with higher quality. Signed-off-by: "Huang, Ying" Cc: Michal Hocko Cc: Minchan Kim Cc: Tim Chen Cc: Hugh Dickins --- mm/swapfile.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index a0a123e59ce6..2ec8b21201d6 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3220,7 +3220,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specia= lfile, int, swap_flags) * select a random position to start with to help wear leveling * SSD */ - p->cluster_next =3D 1 + (prandom_u32() % p->highest_bit); + p->cluster_next =3D 1 + prandom_u32_max(p->highest_bit); nr_cluster =3D DIV_ROUND_UP(maxpages, SWAPFILE_CLUSTER); =20 cluster_info =3D kvcalloc(nr_cluster, sizeof(*cluster_info), --=20 2.26.2