From patchwork Thu Jul 27 08:04:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 13329672 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 E220CC001DC for ; Thu, 27 Jul 2023 08:27:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233990AbjG0I1S (ORCPT ); Thu, 27 Jul 2023 04:27:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34424 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233965AbjG0I0i (ORCPT ); Thu, 27 Jul 2023 04:26:38 -0400 Received: from mail-pf1-x431.google.com (mail-pf1-x431.google.com [IPv6:2607:f8b0:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 456044EEB for ; Thu, 27 Jul 2023 01:14:04 -0700 (PDT) Received: by mail-pf1-x431.google.com with SMTP id d2e1a72fcca58-686f74a8992so78331b3a.1 for ; Thu, 27 Jul 2023 01:14:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1690445600; x=1691050400; 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=f+7Rjo519K3FhaZ9jqPWNUITMom2L2BqSXFVMuCYJXE=; b=iCbLBUqUt9Nmpfx9vnMv71z6ZoxeAA3Kwx+3hOoXd1GaTMzDfIKBdQZJLnwkBZI0pa Lp64e3iwzE/rImCGGIb1ibgUBPxOPSIGFFuuYRtSxlo+aqH0+DTZDA4mGtoxEeFwJjn7 eVXRc7yr9jM32bf+/xn99rZxVedfvtJlhFw9fGMGNkAD3ORupJUg3X+ANXG24/AH/vl7 jpmLaXt1oCEYJ/yvLZ0XDwvzYMWndPPs0hfwCexWDUJDE/XQyc02dMzlI6K63u7Ep8SN XNSeVfJxqvuXvz57tL/Yxcln+9J35CIKIXgWOW2mH/cpcfLsA9vX9cNULDu6wCRYP4Zg 0nEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690445600; x=1691050400; 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=f+7Rjo519K3FhaZ9jqPWNUITMom2L2BqSXFVMuCYJXE=; b=krmRL6/Tkdi/9pO/JQKmX/mBBX4NeacbFzoztZF8H4Ir/uNCPVR1jPe6QThj9ESUBM eSlquwN03XVAClL/W75i41M3Yf9NY5KQ6NHBeS/U8CV/65RN96sYGdjM5xL14Q4d9fUl YbWCOSJBoF3OsqZH/pMipPX+hjWL5jXEYjUC8+YWoRKbccygjernTNgAA6SEFM+Mmzme QvcNoiklyLABSvZkLpq2DwBbHX+etpJHDr1m5Fp0nEId2ERSHDv6PAdiHvRQbf9ZC9bh 4tGiDACUmgDGMgwLTOZCFCO4sKWYHVpsxA1NQGX0OYpumD72lnUAZM5qZG2GQLwkxH/+ krQQ== X-Gm-Message-State: ABy/qLY0+1MZy9kv04iZHKaUZ2vMA/0f4xU3flBrOVJVKDW8EGZLItGR 57+zgVEyLgzEffh4Bmbn3W0lTQ== X-Google-Smtp-Source: APBJJlFVIfpGcg6LJptv9vKKDXXp5NoXAxRgeIF2Co73Rpi3BTRYlDiWRgj+jM16dBQ5q2UaSpGRNg== X-Received: by 2002:a05:6a20:729a:b0:100:b92b:e8be with SMTP id o26-20020a056a20729a00b00100b92be8bemr5583609pzk.2.1690445600629; Thu, 27 Jul 2023 01:13:20 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([203.208.167.147]) by smtp.gmail.com with ESMTPSA id j8-20020aa78d08000000b006828e49c04csm885872pfe.75.2023.07.27.01.13.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 Jul 2023 01:13:20 -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, x86@kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, linux-erofs@lists.ozlabs.org, linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com, linux-nfs@vger.kernel.org, linux-mtd@lists.infradead.org, rcu@vger.kernel.org, netdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, dm-devel@redhat.com, linux-raid@vger.kernel.org, linux-bcache@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, Qi Zheng , Chuck Lever , Jeff Layton Subject: [PATCH v3 37/49] nfsd: dynamically allocate the nfsd-reply shrinker Date: Thu, 27 Jul 2023 16:04:50 +0800 Message-Id: <20230727080502.77895-38-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230727080502.77895-1-zhengqi.arch@bytedance.com> References: <20230727080502.77895-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the nfsd-reply shrinker, so that it can be freed asynchronously using kfree_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 --- 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; - struct shrinker nfsd_reply_cache_shrinker; + struct shrinker *nfsd_reply_cache_shrinker; /* 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 = 0; nn->max_drc_entries = nfsd_cache_size_limit(); atomic_set(&nn->num_drc_entries, 0); hashsize = nfsd_hashsize(nn->max_drc_entries); nn->maskbits = ilog2(hashsize); - nn->nfsd_reply_cache_shrinker.scan_objects = nfsd_reply_cache_scan; - nn->nfsd_reply_cache_shrinker.count_objects = nfsd_reply_cache_count; - nn->nfsd_reply_cache_shrinker.seeks = 1; - status = register_shrinker(&nn->nfsd_reply_cache_shrinker, - "nfsd-reply:%s", nn->nfsd_name); - if (status) - return status; - nn->drc_hashtbl = kvzalloc(array_size(hashsize, sizeof(*nn->drc_hashtbl)), GFP_KERNEL); if (!nn->drc_hashtbl) + return -ENOMEM; + + nn->nfsd_reply_cache_shrinker = shrinker_alloc(0, "nfsd-reply:%s", + nn->nfsd_name); + if (!nn->nfsd_reply_cache_shrinker) goto out_shrinker; + nn->nfsd_reply_cache_shrinker->scan_objects = nfsd_reply_cache_scan; + nn->nfsd_reply_cache_shrinker->count_objects = nfsd_reply_cache_count; + nn->nfsd_reply_cache_shrinker->seeks = 1; + nn->nfsd_reply_cache_shrinker->private_data = nn; + + shrinker_register(nn->nfsd_reply_cache_shrinker); + for (i = 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) 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; - unregister_shrinker(&nn->nfsd_reply_cache_shrinker); + shrinker_free(nn->nfsd_reply_cache_shrinker); for (i = 0; i < nn->drc_hashsize; i++) { struct list_head *head = &nn->drc_hashtbl[i].lru_head; @@ -323,8 +326,7 @@ nfsd_prune_bucket_locked(struct nfsd_net *nn, struct nfsd_drc_bucket *b, static unsigned long nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc) { - struct nfsd_net *nn = container_of(shrink, - struct nfsd_net, nfsd_reply_cache_shrinker); + struct nfsd_net *nn = shrink->private_data; 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 = container_of(shrink, - struct nfsd_net, nfsd_reply_cache_shrinker); + struct nfsd_net *nn = shrink->private_data; unsigned long freed = 0; LIST_HEAD(dispose); unsigned int i;