From patchwork Thu Jul 1 01:50:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12353183 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED 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 73F71C11F66 for ; Thu, 1 Jul 2021 01:50:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2B0B36146D for ; Thu, 1 Jul 2021 01:50:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2B0B36146D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A388A8D0212; Wed, 30 Jun 2021 21:50:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9E89E8D0202; Wed, 30 Jun 2021 21:50:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8B1088D0212; Wed, 30 Jun 2021 21:50:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0056.hostedemail.com [216.40.44.56]) by kanga.kvack.org (Postfix) with ESMTP id 650758D0202 for ; Wed, 30 Jun 2021 21:50:32 -0400 (EDT) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 3848E25F5A for ; Thu, 1 Jul 2021 01:50:32 +0000 (UTC) X-FDA: 78312339504.31.382C11C Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf22.hostedemail.com (Postfix) with ESMTP id E55411983 for ; Thu, 1 Jul 2021 01:50:31 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 140BA61468; Thu, 1 Jul 2021 01:50:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1625104231; bh=bMZghlfwKOQnCH7xwNfRdzA6t6/oFT5kgSFzQsMvzLU=; h=Date:From:To:Subject:In-Reply-To:From; b=h70G1lb7JeJ6TBPZyfMTFkVEsiQ5fC8NEni3BBtOjpm+A7KMHmmPnPWSDJqXEg7wf IpFWWcDSqUD+NdSq5+bW2HyztgBYAKisFbfTk8LCq4OPar7lV7wEm9TRlIX66APfu2 Xhyfmb7EBkctktQyyplQblvNp/Sg6IJVQ0zpVrRo= Date: Wed, 30 Jun 2021 18:50:30 -0700 From: Andrew Morton To: akpm@linux-foundation.org, hdanton@sina.com, linmiaohe@huawei.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, vitaly.wool@konsulko.com Subject: [patch 062/192] mm/z3fold: remove magic number in z3fold_create_pool() Message-ID: <20210701015030.igMLYc0-G%akpm@linux-foundation.org> In-Reply-To: <20210630184624.9ca1937310b0dd5ce66b30e7@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: E55411983 X-Stat-Signature: wy9tjgc8ys9nihtk9bnxrojfzh7tsqks Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=h70G1lb7; dmarc=none; spf=pass (imf22.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-HE-Tag: 1625104231-136727 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: From: Miaohe Lin Subject: mm/z3fold: remove magic number in z3fold_create_pool() It's meaningless to pass a magic number 2 to __alloc_percpu() as there is a minimum alignment size of PCPU_MIN_ALLOC_SIZE (> 2) in it. Also there is no special alignment requirement for unbuddied. So we could replace this magic number with nature alignment, i.e. __alignof__(struct list_head), to improve readability. Link: https://lkml.kernel.org/r/20210619093151.1492174-4-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Reviewed-by: Vitaly Wool Cc: Hillf Danton Signed-off-by: Andrew Morton --- mm/z3fold.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/z3fold.c~mm-z3fold-remove-magic-number-in-z3fold_create_pool +++ a/mm/z3fold.c @@ -998,7 +998,8 @@ static struct z3fold_pool *z3fold_create goto out_c; spin_lock_init(&pool->lock); spin_lock_init(&pool->stale_lock); - pool->unbuddied = __alloc_percpu(sizeof(struct list_head)*NCHUNKS, 2); + pool->unbuddied = __alloc_percpu(sizeof(struct list_head) * NCHUNKS, + __alignof__(struct list_head)); if (!pool->unbuddied) goto out_pool; for_each_possible_cpu(cpu) {