From mboxrd@z Thu Jan 1 00:00:00 1970 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 BA37FC0015E for ; Mon, 24 Jul 2023 12:18:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230368AbjGXMST (ORCPT ); Mon, 24 Jul 2023 08:18:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbjGXMSS (ORCPT ); Mon, 24 Jul 2023 08:18:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 32FCA170D; Mon, 24 Jul 2023 05:17:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8A55C61124; Mon, 24 Jul 2023 12:17:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE84DC433C7; Mon, 24 Jul 2023 12:17:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690201064; bh=QrEpSq7cPtZ3cWIhHPElPK38cx6jwtPbdBU+j7U7fKM=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=lFo5/uyfnIZhAXSNnfYH/zs0wLPvsdGmMHFPu1gPwZUyuOP10nfFnm2e23E9mVHox RPTdsfQNauiU49m1hBahLSzV9+gtG/J7umAiMCAj2AameE5Kr8rrBCOJ9W6HPjIMkc lBp1NfEAIBufJmTKwy4+ZdRStOdLezK2HhFQXgRbYXDnNec/zH0oZOEiZUwOk3URR0 CwbOA3I9uES6cdgV2JXRUz8O/MvIwDzgSFlH2Jg5PAfwuqtmwK87bHc16vNtVYlbJG hfzmJLudml4J90E2WDeTwJcjuLZaZewiSQ45z8+KBeEkpGI5axaDFLzZmilBUDvalQ cGU58i/dTyQGA== Message-ID: <01e8445d033314b6d9cd67bece74ca1c3ce89945.camel@kernel.org> Subject: Re: [PATCH v2 34/47] nfsd: dynamically allocate the nfsd-client shrinker From: Jeff Layton To: Qi Zheng , 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, Chuck Lever Date: Mon, 24 Jul 2023 08:17:39 -0400 In-Reply-To: <20230724094354.90817-35-zhengqi.arch@bytedance.com> References: <20230724094354.90817-1-zhengqi.arch@bytedance.com> <20230724094354.90817-35-zhengqi.arch@bytedance.com> Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.48.4 (3.48.4-1.fc38) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, 2023-07-24 at 17:43 +0800, Qi Zheng wrote: > In preparation for implementing lockless slab shrink, use new APIs to > dynamically allocate the nfsd-client 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. >=20 > Acked-by: Chuck Lever > Signed-off-by: Qi Zheng > --- > fs/nfsd/netns.h | 2 +- > fs/nfsd/nfs4state.c | 20 ++++++++++++-------- > 2 files changed, 13 insertions(+), 9 deletions(-) >=20 > diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h > index ec49b200b797..f669444d5336 100644 > --- a/fs/nfsd/netns.h > +++ b/fs/nfsd/netns.h > @@ -195,7 +195,7 @@ struct nfsd_net { > int nfs4_max_clients; > =20 > atomic_t nfsd_courtesy_clients; > - struct shrinker nfsd_client_shrinker; > + struct shrinker *nfsd_client_shrinker; > struct work_struct nfsd_shrinker_work; > }; > =20 > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index 3339177f8e2f..c7a4616cd866 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -4388,8 +4388,7 @@ static unsigned long > nfsd4_state_shrinker_count(struct shrinker *shrink, struct shrink_contro= l *sc) > { > int count; > - struct nfsd_net *nn =3D container_of(shrink, > - struct nfsd_net, nfsd_client_shrinker); > + struct nfsd_net *nn =3D shrink->private_data; > =20 > count =3D atomic_read(&nn->nfsd_courtesy_clients); > if (!count) > @@ -8125,12 +8124,17 @@ static int nfs4_state_create_net(struct net *net) > INIT_WORK(&nn->nfsd_shrinker_work, nfsd4_state_shrinker_worker); > get_net(net); > =20 > - nn->nfsd_client_shrinker.scan_objects =3D nfsd4_state_shrinker_scan; > - nn->nfsd_client_shrinker.count_objects =3D nfsd4_state_shrinker_count; > - nn->nfsd_client_shrinker.seeks =3D DEFAULT_SEEKS; > - > - if (register_shrinker(&nn->nfsd_client_shrinker, "nfsd-client")) > + nn->nfsd_client_shrinker =3D shrinker_alloc(0, "nfsd-client"); > + if (!nn->nfsd_client_shrinker) > goto err_shrinker; > + > + nn->nfsd_client_shrinker->scan_objects =3D nfsd4_state_shrinker_scan; > + nn->nfsd_client_shrinker->count_objects =3D nfsd4_state_shrinker_count; > + nn->nfsd_client_shrinker->seeks =3D DEFAULT_SEEKS; > + nn->nfsd_client_shrinker->private_data =3D nn; > + > + shrinker_register(nn->nfsd_client_shrinker); > + > return 0; > =20 > err_shrinker: > @@ -8228,7 +8232,7 @@ nfs4_state_shutdown_net(struct net *net) > struct list_head *pos, *next, reaplist; > struct nfsd_net *nn =3D net_generic(net, nfsd_net_id); > =20 > - unregister_shrinker(&nn->nfsd_client_shrinker); > + shrinker_unregister(nn->nfsd_client_shrinker); > cancel_work(&nn->nfsd_shrinker_work); > cancel_delayed_work_sync(&nn->laundromat_work); > locks_end_grace(&nn->nfsd4_manager); Acked-by: Jeff Layton