Return-Path: Received: from mx2.suse.de ([195.135.220.15]:38731 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750771AbeD3EcE (ORCPT ); Mon, 30 Apr 2018 00:32:04 -0400 From: NeilBrown To: "Paul E. McKenney" , Trond Myklebust , Mathieu Desnoyers , Anna Schumaker Date: Mon, 30 Apr 2018 14:31:30 +1000 Subject: [PATCH 1/4] NFS: slight optimization for walking list for delegations Cc: linux-nfs@vger.kernel.org, Lai Jiangshan , Josh Triplett , Steven Rostedt , linux-kernel@vger.kernel.org Message-ID: <152506269054.7246.3941740801391514623.stgit@noble> In-Reply-To: <152506256513.7246.13171564155614823841.stgit@noble> References: <152506256513.7246.13171564155614823841.stgit@noble> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: There are 3 places where we walk the list of delegations for an nfs_client. In each case there are two nested loops, one for nfs_servers and one for nfs_delegations. When we find an interesting delegation we try to get an active reference to the server. If that fails, it is pointless to continue to look at the other delegation for the server as we will never be able to get an active reference. So instead of continuing in the inner loop, break out and continue in the outer loop. --- fs/nfs/delegation.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index 1819d0d0ba4b..af32365894c8 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -495,7 +495,7 @@ int nfs_client_return_marked_delegations(struct nfs_client *clp) if (!nfs_delegation_need_return(delegation)) continue; if (!nfs_sb_active(server->super)) - continue; + break; inode = nfs_delegation_grab_inode(delegation); if (inode == NULL) { rcu_read_unlock(); @@ -887,7 +887,7 @@ void nfs_delegation_reap_unclaimed(struct nfs_client *clp) &delegation->flags) == 0) continue; if (!nfs_sb_active(server->super)) - continue; + break; inode = nfs_delegation_grab_inode(delegation); if (inode == NULL) { rcu_read_unlock(); @@ -995,7 +995,7 @@ void nfs_reap_expired_delegations(struct nfs_client *clp) &delegation->flags) == 0) continue; if (!nfs_sb_active(server->super)) - continue; + break; inode = nfs_delegation_grab_inode(delegation); if (inode == NULL) { rcu_read_unlock();