From patchwork Mon Aug 23 13:25:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 12452863 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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, 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 877DCC4320A for ; Mon, 23 Aug 2021 13:25:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1DB2961374 for ; Mon, 23 Aug 2021 13:25:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1DB2961374 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id B03E66B0072; Mon, 23 Aug 2021 09:25:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AB2968D0001; Mon, 23 Aug 2021 09:25:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 979D16B0074; Mon, 23 Aug 2021 09:25:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0201.hostedemail.com [216.40.44.201]) by kanga.kvack.org (Postfix) with ESMTP id 7C0176B0072 for ; Mon, 23 Aug 2021 09:25:26 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 24B0D248BB for ; Mon, 23 Aug 2021 13:25:26 +0000 (UTC) X-FDA: 78506417052.27.F643597 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf16.hostedemail.com (Postfix) with ESMTP id B5A3BF00009B for ; Mon, 23 Aug 2021 13:25:25 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id D9B9061373; Mon, 23 Aug 2021 13:25:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629725125; bh=43OttOoA+izE3bbLjhYbj+Uvn2nbLJSqbfY6UbauX60=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FwBAEvyYU68YR66QYkCvLp/UcpgFL3duRG70qZ2A4lA8BrU0x6jHAZYeGgp1amwqu afOnmIVmw98H4hHFdzx0IreEinrtA8UTYsAlnSQViHjCXz2yviZvTKEKJpFxuD8HkT DRO0N4Q6aJkHGldSsy95NrvKdouarsTMvULBQRvqt7tkskWClXqogS0ETI8k0v7fzB sEYDY1eBvfyo/fYeHuOmZU0DxvDFUmBojV6bgIMo5mrifSvG0eXqaOJ1uA1CPIOdSA q7JwncGNNyTNTOoV0OBGpIoVYmKUuP8wzh8hOe+DdeZ4fXgacQecZRDykl+utC4mov pERKRUDFUM6wg== From: Mike Rapoport To: linux-mm@kvack.org Cc: Andrew Morton , Andy Lutomirski , Dave Hansen , Ira Weiny , Kees Cook , Mike Rapoport , Mike Rapoport , Peter Zijlstra , Rick Edgecombe , Vlastimil Babka , x86@kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH 1/4] list: Support getting most recent element in list_lru Date: Mon, 23 Aug 2021 16:25:10 +0300 Message-Id: <20210823132513.15836-2-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20210823132513.15836-1-rppt@kernel.org> References: <20210823132513.15836-1-rppt@kernel.org> MIME-Version: 1.0 Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=FwBAEvyY; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf16.hostedemail.com: domain of rppt@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=rppt@kernel.org X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: B5A3BF00009B X-Stat-Signature: bxordyf919waw5459xdwifo8u8pdfxor X-HE-Tag: 1629725125-598799 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: Rick Edgecombe In future patches, some functionality will use list_lru that also needs to keep track of the most recently used element on a node. Since this information is already contained within list_lru, add a function to get it so that an additional list is not needed in the caller. Do not support memcg aware list_lru's since it is not needed by the intended caller. Signed-off-by: Rick Edgecombe --- include/linux/list_lru.h | 13 +++++++++++++ mm/list_lru.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+) diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h index 1b5fceb565df..08e07c19fd13 100644 --- a/include/linux/list_lru.h +++ b/include/linux/list_lru.h @@ -103,6 +103,19 @@ bool list_lru_add(struct list_lru *lru, struct list_head *item); */ bool list_lru_del(struct list_lru *lru, struct list_head *item); +/** + * list_lru_get_mru: gets and removes the tail from one of the node lists + * @list_lru: the lru pointer + * @nid: the node id + * + * This function removes the most recently added item from one of the node + * id specified. This function should not be used if the list_lru is memcg + * aware. + * + * Return value: The element removed + */ +struct list_head *list_lru_get_mru(struct list_lru *lru, int nid); + /** * list_lru_count_one: return the number of objects currently held by @lru * @lru: the lru pointer. diff --git a/mm/list_lru.c b/mm/list_lru.c index cd58790d0fb3..c1bec58168e1 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -156,6 +156,34 @@ bool list_lru_del(struct list_lru *lru, struct list_head *item) } EXPORT_SYMBOL_GPL(list_lru_del); +struct list_head *list_lru_get_mru(struct list_lru *lru, int nid) +{ + struct list_lru_node *nlru = &lru->node[nid]; + struct list_lru_one *l = &nlru->lru; + struct list_head *ret; + + /* This function does not attempt to search through the memcg lists */ + if (list_lru_memcg_aware(lru)) { + WARN_ONCE(1, "list_lru: %s not supported on memcg aware list_lrus", __func__); + return NULL; + } + + spin_lock(&nlru->lock); + if (list_empty(&l->list)) { + ret = NULL; + } else { + /* Get tail */ + ret = l->list.prev; + list_del_init(ret); + + l->nr_items--; + nlru->nr_items--; + } + spin_unlock(&nlru->lock); + + return ret; +} + void list_lru_isolate(struct list_lru_one *list, struct list_head *item) { list_del_init(item);