From patchwork Tue Nov 16 02:44:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: NeilBrown X-Patchwork-Id: 12621177 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F251AC433F5 for ; Tue, 16 Nov 2021 02:49:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D8E476187F for ; Tue, 16 Nov 2021 02:49:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353126AbhKPCw1 (ORCPT ); Mon, 15 Nov 2021 21:52:27 -0500 Received: from smtp-out2.suse.de ([195.135.220.29]:37462 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352459AbhKPCub (ORCPT ); Mon, 15 Nov 2021 21:50:31 -0500 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 8978E1FD6D; Tue, 16 Nov 2021 02:46:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1637030803; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bh1jN8WGzIi8TEk0QRz2HpNXbcNghbMdw1FTZGlL1Tk=; b=IOKHEEPION2gMxq6pdocbPlQV7E2toIftm5puTYicudmr2y13LSJ+3PNCZKabPzv9GYkBy ShDN3Vzj43Xssc825UNXCOZhHuP5r0NjJ1A9y8GpQeGz18U47wpB7BOnCa0nBZwxRvdVk7 PR2+5Mr3kZUsf6D7O0STIeP8q5sSIjA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1637030803; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bh1jN8WGzIi8TEk0QRz2HpNXbcNghbMdw1FTZGlL1Tk=; b=3198S1+iRUtdM6P1zaeNWvfx8gO2+zobdgNjBqrQI5VM/r6t86DSodV8TezxiF7k+9Qgag Ns9zTD98yVSLTKBw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 348B613B70; Tue, 16 Nov 2021 02:46:40 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 3QktOZAbk2EWCQAAMHmgww (envelope-from ); Tue, 16 Nov 2021 02:46:40 +0000 Subject: [PATCH 10/13] NFSv4: keep state manager thread active if swap is enabled From: NeilBrown To: Trond Myklebust , Anna Schumaker , Chuck Lever , Andrew Morton , Mel Gorman Cc: linux-nfs@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Tue, 16 Nov 2021 13:44:04 +1100 Message-ID: <163703064456.25805.6410751202807765149.stgit@noble.brown> In-Reply-To: <163702956672.25805.16457749992977493579.stgit@noble.brown> References: <163702956672.25805.16457749992977493579.stgit@noble.brown> User-Agent: StGit/0.23 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org If we are swapping over NFSv4, we may not be able to allocate memory to start the state-manager thread at the time when we need it. So keep it always running when swap is enabled, and just signal it to start. This requires updating and testing the cl_swapper count on the root rpc_clnt after following all ->cl_parent links. Signed-off-by: NeilBrown --- fs/nfs/file.c | 19 +++++++++++++++---- fs/nfs/nfs4_fs.h | 1 + fs/nfs/nfs4proc.c | 20 ++++++++++++++++++++ fs/nfs/nfs4state.c | 39 +++++++++++++++++++++++++++++++++------ include/linux/nfs_xdr.h | 2 ++ net/sunrpc/clnt.c | 2 ++ 6 files changed, 73 insertions(+), 10 deletions(-) diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 45d8180b7be3..59c271f42ea5 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -489,8 +489,10 @@ static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file, { unsigned long blocks; long long isize; - struct rpc_clnt *clnt = NFS_CLIENT(file->f_mapping->host); - struct inode *inode = file->f_mapping->host; + struct inode *inode = file_inode(file); + struct rpc_clnt *clnt = NFS_CLIENT(inode); + struct nfs_client *cl = NFS_SERVER(inode)->nfs_client; + int ret; spin_lock(&inode->i_lock); blocks = inode->i_blocks; @@ -503,14 +505,23 @@ static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file, *span = sis->pages; - return rpc_clnt_swap_activate(clnt); + ret = rpc_clnt_swap_activate(clnt); + + if (ret == 0 && cl->rpc_ops->enable_swap) + cl->rpc_ops->enable_swap(inode); + + return ret; } static void nfs_swap_deactivate(struct file *file) { - struct rpc_clnt *clnt = NFS_CLIENT(file->f_mapping->host); + struct inode *inode = file_inode(file); + struct rpc_clnt *clnt = NFS_CLIENT(inode); + struct nfs_client *cl = NFS_SERVER(inode)->nfs_client; rpc_clnt_swap_deactivate(clnt); + if (cl->rpc_ops->disable_swap) + cl->rpc_ops->disable_swap(file_inode(file)); } const struct address_space_operations nfs_file_aops = { diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h index ed5eaca6801e..8a9ce0f42efd 100644 --- a/fs/nfs/nfs4_fs.h +++ b/fs/nfs/nfs4_fs.h @@ -42,6 +42,7 @@ enum nfs4_client_state { NFS4CLNT_LEASE_MOVED, NFS4CLNT_DELEGATION_EXPIRED, NFS4CLNT_RUN_MANAGER, + NFS4CLNT_MANAGER_AVAILABLE, NFS4CLNT_RECALL_RUNNING, NFS4CLNT_RECALL_ANY_LAYOUT_READ, NFS4CLNT_RECALL_ANY_LAYOUT_RW, diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index ee3bc79f6ca3..ab6382f9cbf0 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -10347,6 +10347,24 @@ static ssize_t nfs4_listxattr(struct dentry *dentry, char *list, size_t size) return error + error2 + error3; } +static void nfs4_enable_swap(struct inode *inode) +{ + /* The state manager thread must always be running. + * It will notice the client is a swapper, and stay put. + */ + struct nfs_client *clp = NFS_SERVER(inode)->nfs_client; + + nfs4_schedule_state_manager(clp); +} + +static void nfs4_disable_swap(struct inode *inode) +{ + /* The state manager thread will now exit once it is + * woken. + */ + wake_up_var(&NFS_SERVER(inode)->nfs_client->cl_state); +} + static const struct inode_operations nfs4_dir_inode_operations = { .create = nfs_create, .lookup = nfs_lookup, @@ -10423,6 +10441,8 @@ const struct nfs_rpc_ops nfs_v4_clientops = { .free_client = nfs4_free_client, .create_server = nfs4_create_server, .clone_server = nfs_clone_server, + .enable_swap = nfs4_enable_swap, + .disable_swap = nfs4_disable_swap, }; static const struct xattr_handler nfs4_xattr_nfs4_acl_handler = { diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index ecc4594299d6..2408e9b98f68 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1205,10 +1205,17 @@ void nfs4_schedule_state_manager(struct nfs_client *clp) { struct task_struct *task; char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1]; + struct rpc_clnt *cl = clp->cl_rpcclient; + + while (cl != cl->cl_parent) + cl = cl->cl_parent; set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state); - if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0) + if (test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state) != 0) { + wake_up_var(&clp->cl_state); return; + } + set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state); __module_get(THIS_MODULE); refcount_inc(&clp->cl_count); @@ -1224,6 +1231,7 @@ void nfs4_schedule_state_manager(struct nfs_client *clp) printk(KERN_ERR "%s: kthread_run: %ld\n", __func__, PTR_ERR(task)); nfs4_clear_state_manager_bit(clp); + clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state); nfs_put_client(clp); module_put(THIS_MODULE); } @@ -2661,11 +2669,8 @@ static void nfs4_state_manager(struct nfs_client *clp) clear_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state); } - /* Did we race with an attempt to give us more work? */ - if (!test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state)) - return; - if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0) - return; + return; + } while (refcount_read(&clp->cl_count) > 1 && !signalled()); goto out_drain; @@ -2685,9 +2690,31 @@ static void nfs4_state_manager(struct nfs_client *clp) static int nfs4_run_state_manager(void *ptr) { struct nfs_client *clp = ptr; + struct rpc_clnt *cl = clp->cl_rpcclient; + + while (cl != cl->cl_parent) + cl = cl->cl_parent; allow_signal(SIGKILL); +again: + set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state); nfs4_state_manager(clp); + if (atomic_read(&cl->cl_swapper)) { + wait_var_event_interruptible(&clp->cl_state, + test_bit(NFS4CLNT_RUN_MANAGER, + &clp->cl_state)); + if (atomic_read(&cl->cl_swapper) && + test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state)) + goto again; + /* Either no longer a swapper, or were signalled */ + } + clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state); + + if (refcount_read(&clp->cl_count) > 1 && !signalled() && + test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) && + !test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state)) + goto again; + nfs_put_client(clp); module_put_and_exit(0); return 0; diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index 967a0098f0a9..04cf3a8fb949 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -1795,6 +1795,8 @@ struct nfs_rpc_ops { struct nfs_server *(*create_server)(struct fs_context *); struct nfs_server *(*clone_server)(struct nfs_server *, struct nfs_fh *, struct nfs_fattr *, rpc_authflavor_t); + void (*enable_swap)(struct inode *inode); + void (*disable_swap)(struct inode *inode); }; /* diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index cb76fbea3ed5..4cb403a0f334 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -3066,6 +3066,8 @@ rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, int rpc_clnt_swap_activate(struct rpc_clnt *clnt) { + while (clnt != clnt->cl_parent) + clnt = clnt->cl_parent; if (atomic_inc_return(&clnt->cl_swapper) == 1) return rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_swap_activate_callback, NULL);