From: Chuck Lever Subject: [PATCH 3/3] NLM/NFS: Use cached nlm_host when calling nlmclnt_proc() Date: Wed, 09 Jan 2008 12:20:25 -0500 Message-ID: <20080109172025.7067.59204.stgit@manray.1015granger.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Cc: linux-nfs@vger.kernel.org To: trond.myklebust@fys.uio.no Return-path: Received: from flpi195.sbcis.sbc.com ([207.115.20.197]:44177 "EHLO flpi195.prodigy.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752810AbYAIRUb (ORCPT ); Wed, 9 Jan 2008 12:20:31 -0500 Sender: linux-nfs-owner@vger.kernel.org List-ID: Now that each NFS mount point caches its own nlm_host structure, it can be passed to nlmclnt_proc() for each lock request. By pinning an nlm_host for each mount point, we trade the overhead of looking up or creating a fresh nlm_host struct during every NLM procedure call for a little extra memory. We also restrict the nlmclnt_proc symbol to limit the use of this call to in-tree modules. Note that nlm_lookup_host() (just removed from the client's per-request NLM processing) could also trigger an nlm_host garbage collection. Now client-side nlm_host garbage collection occurs only during NFS mount processing. Since the NFS client now holds a reference on these nlm_host structures, they wouldn't have been affected by garbage collection anyway. Given that nlm_lookup_host() reorders the global nlm_host chain after every successful lookup, and that a garbage collection could be triggered during the call, we've removed a significant amount of per-NLM-request CPU processing overhead. Sidebar: there are only a few remaining references to the internals of NFS inodes in the client-side NLM code. The only references I found are related to extracting or comparing the inode's file handle via NFS_FH(). One is in nlmclnt_grant(); the other is in nlmclnt_setlockargs(). Signed-off-by: Chuck Lever --- fs/lockd/clntproc.c | 33 ++++++++++----------------------- fs/nfs/nfs3proc.c | 4 +++- fs/nfs/proc.c | 4 +++- include/linux/lockd/bind.h | 3 ++- 4 files changed, 18 insertions(+), 26 deletions(-) diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c index a10343b..b1a4dba 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -145,34 +145,21 @@ static void nlmclnt_release_lockargs(struct nlm_rqst *req) BUG_ON(req->a_args.lock.fl.fl_ops != NULL); } -/* - * This is the main entry point for the NLM client. +/** + * nlmclnt_proc - Perform a single client-side lock request + * @host: address of a valid nlm_host context representing the NLM server + * @cmd: fcntl-style file lock operation to perform + * @fl: address of arguments for the lock operation + * */ -int -nlmclnt_proc(struct inode *inode, int cmd, struct file_lock *fl) +int nlmclnt_proc(struct nlm_host *host, int cmd, struct file_lock *fl) { - struct rpc_clnt *client = NFS_CLIENT(inode); - struct sockaddr_in addr; - struct nfs_server *nfssrv = NFS_SERVER(inode); - struct nlm_host *host; struct nlm_rqst *call; sigset_t oldset; unsigned long flags; - int status, vers; - - vers = (NFS_PROTO(inode)->version == 3) ? 4 : 1; - if (NFS_PROTO(inode)->version > 3) { - printk(KERN_NOTICE "NFSv4 file locking not implemented!\n"); - return -ENOLCK; - } - - rpc_peeraddr(client, (struct sockaddr *) &addr, sizeof(addr)); - host = nlmclnt_lookup_host(&addr, client->cl_xprt->prot, vers, - nfssrv->nfs_client->cl_hostname, - strlen(nfssrv->nfs_client->cl_hostname)); - if (host == NULL) - return -ENOLCK; + int status; + nlm_get_host(host); call = nlm_alloc_call(host); if (call == NULL) return -ENOMEM; @@ -219,7 +206,7 @@ nlmclnt_proc(struct inode *inode, int cmd, struct file_lock *fl) dprintk("lockd: clnt proc returns %d\n", status); return status; } -EXPORT_SYMBOL(nlmclnt_proc); +EXPORT_SYMBOL_GPL(nlmclnt_proc); /* * Allocate an NLM RPC call struct diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c index 4cdc236..c11bb6a 100644 --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -796,7 +796,9 @@ static void nfs3_proc_commit_setup(struct nfs_write_data *data, int how) static int nfs3_proc_lock(struct file *filp, int cmd, struct file_lock *fl) { - return nlmclnt_proc(filp->f_path.dentry->d_inode, cmd, fl); + struct inode *inode = filp->f_path.dentry->d_inode; + + return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl); } const struct nfs_rpc_ops nfs_v3_clientops = { diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c index 4f80d88..c3fe1bc 100644 --- a/fs/nfs/proc.c +++ b/fs/nfs/proc.c @@ -609,7 +609,9 @@ nfs_proc_commit_setup(struct nfs_write_data *data, int how) static int nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl) { - return nlmclnt_proc(filp->f_path.dentry->d_inode, cmd, fl); + struct inode *inode = filp->f_path.dentry->d_inode; + + return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl); } diff --git a/include/linux/lockd/bind.h b/include/linux/lockd/bind.h index 372c8df..59d51f1 100644 --- a/include/linux/lockd/bind.h +++ b/include/linux/lockd/bind.h @@ -42,7 +42,8 @@ extern struct nlm_host *nlmclnt_init(struct sockaddr *server_address, unsigned short protocol); extern void nlmclnt_done(struct nlm_host *host); -extern int nlmclnt_proc(struct inode *, int, struct file_lock *); +extern int nlmclnt_proc(struct nlm_host *host, int cmd, + struct file_lock *fl); extern int lockd_up(int proto); extern void lockd_down(void);