From nobody Thu Sep 11 22:30:52 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3700DCA0ED7 for ; Mon, 11 Sep 2023 21:38:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348971AbjIKVcA (ORCPT ); Mon, 11 Sep 2023 17:32:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56228 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236086AbjIKJuh (ORCPT ); Mon, 11 Sep 2023 05:50:37 -0400 Received: from mail-pl1-x630.google.com (mail-pl1-x630.google.com [IPv6:2607:f8b0:4864:20::630]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F5E5E40 for ; Mon, 11 Sep 2023 02:50:12 -0700 (PDT) Received: by mail-pl1-x630.google.com with SMTP id d9443c01a7336-1c3aa44c0faso1787945ad.1 for ; Mon, 11 Sep 2023 02:50:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1694425812; x=1695030612; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=iZYFEziqHKQTs36ii9IxaHzQyRy7+HnptX1eUkyxsok=; b=WZBENGkSXaOlhHMO5LTxiUcRjhu4geO0M8eetJgadZ9CGfhrcI19ti6aOWT02a9vRm zrXlYh2qg9j1QfwHpRifi/g/K66enkGSJUf7fStZgWMRAasTMKBvhuWzUj0ZB41lrY9F lMjT3MH5zJOwjiBIEI/7xYhZFeS714kq6ci13hhN+O/ftKzbj/Z4ePCgeMqpb6fcKfpn u8JBWiXo94n41UwLigv9QwRhXiKy5v6m42mn2YjeCbgDf2l2jD9/Ev37pAQYF1UROlWy 6U1/fJ0/JpEuXYzT5hwoAv4Qw1JggqVi7K2aR2nBquQfcj6Abt78wj0mSZcxz8yAUQYj SQ3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694425812; x=1695030612; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=iZYFEziqHKQTs36ii9IxaHzQyRy7+HnptX1eUkyxsok=; b=H0DTjsWhna/1xmRVj59Kj4A0NqpnUmYXTag3knESNa8LSA023Yvyh+RwOa5aWShDW2 BTcqucL5W+wo45VNOqZWUifcGKE2FsWQ/NUInhkJETZ2DrVbN2Pbb4OJdcHeG4F6n0Qf e/zOU8yDfss8fQPvXawxx39L5qihreChAx+QhLpe0ijpBKhY8iBb4LfnqViIWdNO5zlW SgWq9kiXO5Ov7SF0+ehpeh9HJ2l64nKcLqtsHJmcTo9hHcWZk2vqKmY1eoZjboXtHyA9 ML8OWB9KZopj+L1RG0GI1eO9mW3Ndi694zFHaNGpyUGn1ePOjWaLBmvmuT9CO8vKoRKC CAxw== X-Gm-Message-State: AOJu0Yx2uRdN8kPJuqyW54kebhBuTWy1kLi/bKmn7+/cDxW9gd+t40KM rNnKKDFMqQRtnC10ba+wXVKBxQ== X-Google-Smtp-Source: AGHT+IFx01yGZSAgnlbIN2EmaqAGM45aSzdAGkHUGYMQpSItramkO401wN4MdrY4LUd5pZ7aoS8pCA== X-Received: by 2002:a17:902:e84c:b0:1bf:349f:b85c with SMTP id t12-20020a170902e84c00b001bf349fb85cmr11526001plg.1.1694425811998; Mon, 11 Sep 2023 02:50:11 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([203.208.167.146]) by smtp.gmail.com with ESMTPSA id az7-20020a170902a58700b001bdc2fdcf7esm5988188plb.129.2023.09.11.02.50.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Sep 2023 02:50:11 -0700 (PDT) From: Qi Zheng To: akpm@linux-foundation.org, david@fromorbit.com, tkhai@ya.ru, vbabka@suse.cz, roman.gushchin@linux.dev, djwong@kernel.org, brauner@kernel.org, paulmck@kernel.org, tytso@mit.edu, steven.price@arm.com, cel@kernel.org, senozhatsky@chromium.org, yujie.liu@intel.com, gregkh@linuxfoundation.org, muchun.song@linux.dev Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Qi Zheng , Chuck Lever , Jeff Layton , Neil Brown , Olga Kornievskaia , Dai Ngo , Tom Talpey , linux-nfs@vger.kernel.org Subject: [PATCH v6 33/45] nfsd: dynamically allocate the nfsd-reply shrinker Date: Mon, 11 Sep 2023 17:44:32 +0800 Message-Id: <20230911094444.68966-34-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230911094444.68966-1-zhengqi.arch@bytedance.com> References: <20230911094444.68966-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the nfsd-reply shrinker, so that it can be freed asynchronously via RCU. Then it doesn't need to wait for RCU read-side critical section when releasing the struct nfsd_net. Signed-off-by: Qi Zheng Acked-by: Chuck Lever Acked-by: Jeff Layton CC: Neil Brown CC: Olga Kornievskaia CC: Dai Ngo CC: Tom Talpey CC: linux-nfs@vger.kernel.org --- fs/nfsd/netns.h | 2 +- fs/nfsd/nfscache.c | 31 ++++++++++++++++--------------- 2 files changed, 17 insertions(+), 16 deletions(-) diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h index f669444d5336..ab303a8b77d5 100644 --- a/fs/nfsd/netns.h +++ b/fs/nfsd/netns.h @@ -177,7 +177,7 @@ struct nfsd_net { /* size of cache when we saw the longest hash chain */ unsigned int longest_chain_cachesize; =20 - struct shrinker nfsd_reply_cache_shrinker; + struct shrinker *nfsd_reply_cache_shrinker; =20 /* tracking server-to-server copy mounts */ spinlock_t nfsd_ssc_lock; diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c index 80621a709510..fd56a52aa5fb 100644 --- a/fs/nfsd/nfscache.c +++ b/fs/nfsd/nfscache.c @@ -201,26 +201,29 @@ int nfsd_reply_cache_init(struct nfsd_net *nn) { unsigned int hashsize; unsigned int i; - int status =3D 0; =20 nn->max_drc_entries =3D nfsd_cache_size_limit(); atomic_set(&nn->num_drc_entries, 0); hashsize =3D nfsd_hashsize(nn->max_drc_entries); nn->maskbits =3D ilog2(hashsize); =20 - nn->nfsd_reply_cache_shrinker.scan_objects =3D nfsd_reply_cache_scan; - nn->nfsd_reply_cache_shrinker.count_objects =3D nfsd_reply_cache_count; - nn->nfsd_reply_cache_shrinker.seeks =3D 1; - status =3D register_shrinker(&nn->nfsd_reply_cache_shrinker, - "nfsd-reply:%s", nn->nfsd_name); - if (status) - return status; - nn->drc_hashtbl =3D kvzalloc(array_size(hashsize, sizeof(*nn->drc_hashtbl)), GFP_KERNEL); if (!nn->drc_hashtbl) + return -ENOMEM; + + nn->nfsd_reply_cache_shrinker =3D shrinker_alloc(0, "nfsd-reply:%s", + nn->nfsd_name); + if (!nn->nfsd_reply_cache_shrinker) goto out_shrinker; =20 + nn->nfsd_reply_cache_shrinker->scan_objects =3D nfsd_reply_cache_scan; + nn->nfsd_reply_cache_shrinker->count_objects =3D nfsd_reply_cache_count; + nn->nfsd_reply_cache_shrinker->seeks =3D 1; + nn->nfsd_reply_cache_shrinker->private_data =3D nn; + + shrinker_register(nn->nfsd_reply_cache_shrinker); + for (i =3D 0; i < hashsize; i++) { INIT_LIST_HEAD(&nn->drc_hashtbl[i].lru_head); spin_lock_init(&nn->drc_hashtbl[i].cache_lock); @@ -229,7 +232,7 @@ int nfsd_reply_cache_init(struct nfsd_net *nn) =20 return 0; out_shrinker: - unregister_shrinker(&nn->nfsd_reply_cache_shrinker); + kvfree(nn->drc_hashtbl); printk(KERN_ERR "nfsd: failed to allocate reply cache\n"); return -ENOMEM; } @@ -239,7 +242,7 @@ void nfsd_reply_cache_shutdown(struct nfsd_net *nn) struct nfsd_cacherep *rp; unsigned int i; =20 - unregister_shrinker(&nn->nfsd_reply_cache_shrinker); + shrinker_free(nn->nfsd_reply_cache_shrinker); =20 for (i =3D 0; i < nn->drc_hashsize; i++) { struct list_head *head =3D &nn->drc_hashtbl[i].lru_head; @@ -323,8 +326,7 @@ nfsd_prune_bucket_locked(struct nfsd_net *nn, struct nf= sd_drc_bucket *b, static unsigned long nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc) { - struct nfsd_net *nn =3D container_of(shrink, - struct nfsd_net, nfsd_reply_cache_shrinker); + struct nfsd_net *nn =3D shrink->private_data; =20 return atomic_read(&nn->num_drc_entries); } @@ -343,8 +345,7 @@ nfsd_reply_cache_count(struct shrinker *shrink, struct = shrink_control *sc) static unsigned long nfsd_reply_cache_scan(struct shrinker *shrink, struct shrink_control *sc) { - struct nfsd_net *nn =3D container_of(shrink, - struct nfsd_net, nfsd_reply_cache_shrinker); + struct nfsd_net *nn =3D shrink->private_data; unsigned long freed =3D 0; LIST_HEAD(dispose); unsigned int i; --=20 2.30.2