From patchwork Mon Apr 5 20:37:09 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Edgecombe, Rick P" X-Patchwork-Id: 12183579 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 0E448C433ED for ; Mon, 5 Apr 2021 20:41:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9423F613CD for ; Mon, 5 Apr 2021 20:41:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9423F613CD 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 60B596B0073; Mon, 5 Apr 2021 16:41:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 56A016B0078; Mon, 5 Apr 2021 16:41:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 348206B0075; Mon, 5 Apr 2021 16:41:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0227.hostedemail.com [216.40.44.227]) by kanga.kvack.org (Postfix) with ESMTP id 07CE06B0073 for ; Mon, 5 Apr 2021 16:41:40 -0400 (EDT) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id AD265C5CF for ; Mon, 5 Apr 2021 20:41:39 +0000 (UTC) X-FDA: 77999484318.04.85DA205 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by imf11.hostedemail.com (Postfix) with ESMTP id EC44C200024C for ; Mon, 5 Apr 2021 20:41:34 +0000 (UTC) IronPort-SDR: bjlRtkNrAUCesQIz9Ygj/ky3nzRorXHzbMA0R0MBv59qu2kOaE/V1YpRcOg/fi0Ivrx5njmPOn T0qXVIYeXOrQ== X-IronPort-AV: E=McAfee;i="6000,8403,9945"; a="278169238" X-IronPort-AV: E=Sophos;i="5.81,307,1610438400"; d="scan'208";a="278169238" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Apr 2021 13:41:33 -0700 IronPort-SDR: 7hHX1k0TTTvyZ4h8v4pVehE9bJvBiBYeYp/nm8oyolTxqnhRDfifj408AeFJeZmPojn84F2N+v tGkGPIYMXECg== X-IronPort-AV: E=Sophos;i="5.81,307,1610438400"; d="scan'208";a="418078027" Received: from rpedgeco-mobl3.amr.corp.intel.com (HELO localhost.intel.com) ([10.212.230.218]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Apr 2021 13:41:32 -0700 From: Rick Edgecombe To: akpm@linux-foundation.org, linux-mm@kvack.org, bpf@vger.kernel.org, dave.hansen@linux.intel.com, peterz@infradead.org, luto@kernel.org, jeyu@kernel.org Cc: linux-kernel@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, hch@infradead.org, x86@kernel.org, Rick Edgecombe Subject: [RFC 1/3] list: Support getting most recent element in list_lru Date: Mon, 5 Apr 2021 13:37:09 -0700 Message-Id: <20210405203711.1095940-2-rick.p.edgecombe@intel.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210405203711.1095940-1-rick.p.edgecombe@intel.com> References: <20210405203711.1095940-1-rick.p.edgecombe@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: EC44C200024C X-Stat-Signature: t8oxmxdxh13cochs8ge4yum33ohwssn5 X-Rspamd-Server: rspam02 Received-SPF: none (intel.com>: No applicable sender policy available) receiver=imf11; identity=mailfrom; envelope-from=""; helo=mga05.intel.com; client-ip=192.55.52.43 X-HE-DKIM-Result: none/none X-HE-Tag: 1617655294-410895 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: 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 9dcaa3e582c9..4bde44a5024b 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 fe230081690b..a18d9ed8abd5 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);