Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:50231 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751498AbaIRGEV (ORCPT ); Thu, 18 Sep 2014 02:04:21 -0400 From: NeilBrown To: Trond Myklebust , Jeff Layton Date: Thu, 18 Sep 2014 16:03:17 +1000 Subject: [PATCH 0/4] Remove possible deadlocks in nfs_release_page() - V2 Cc: linux-nfs@vger.kernel.org Message-ID: <20140918055907.23854.32118.stgit@notabene.brown> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: These two patches are updated versions of the last two patches of this series. They include the use of congestion to avoid excessive waiting. (I'm not resenting 1/4 and 2/4, they are unchanged). Without the congestion check, I've seen wait times in try_to_free_pages as long as 208 seconds. With no waiting at all in nfs_release_page() I've seen wait times as long as 1.4 seconds. With the 1 second wait, I've seen 2 seconds. These numbers will vary based on numerous factors, but it does seem to suggest that 1 second is a good ball-park number. NeilBrown --- NeilBrown (2): NFS: avoid deadlocks with loop-back mounted NFS filesystems. NFS/SUNRPC: Remove other deadlock-avoidance mechanisms in nfs_release_page() fs/nfs/file.c | 28 ++++++++++++++++++---------- fs/nfs/write.c | 7 +++++++ net/sunrpc/sched.c | 2 -- net/sunrpc/xprtrdma/transport.c | 2 -- net/sunrpc/xprtsock.c | 10 ---------- 5 files changed, 25 insertions(+), 24 deletions(-) -- Signature