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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1AA9DC46475 for ; Tue, 23 Oct 2018 22:45:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E0D5120671 for ; Tue, 23 Oct 2018 22:45:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0D5120671 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729058AbeJXHLC (ORCPT ); Wed, 24 Oct 2018 03:11:02 -0400 Received: from mx2.suse.de ([195.135.220.15]:36228 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725787AbeJXHLC (ORCPT ); Wed, 24 Oct 2018 03:11:02 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 012D5AEAD; Tue, 23 Oct 2018 22:45:35 +0000 (UTC) From: NeilBrown To: Jeff Layton , Alexander Viro Date: Wed, 24 Oct 2018 09:43:54 +1100 Subject: [PATCH 0/9 v3] locks: avoid thundering-herd wake-ups Cc: "J. Bruce Fields" , Martin Wilck , linux-fsdevel@vger.kernel.org, Frank Filz , linux-kernel@vger.kernel.org Message-ID: <154033435272.29542.13985568983074440924.stgit@noble> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This took longer that I had wanted, due to various reasons - sorry. And I'm now posting it in a merge window, which is not ideal. I don't expect it to be included in this merge window and I won't be at all impatient for review, but I didn't want to delay it further. Testing found some problems, particularly the need to use locks_copy_lock in NFS. And there was a small thinko in there that effectively removed all the speed gains :-( But this version: - shows excellent scalability with lots of threads on lots of CPUs contending on a single file - avoids the problems that Bruce found - seems to work. Thanks, NeilBrown --- NeilBrown (9): fs/locks: rename some lists and pointers. fs/locks: split out __locks_wake_up_blocks(). NFS: use locks_copy_lock() to copy locks. fs/locks: allow a lock request to block other requests. fs/locks: always delete_block after waiting. fs/locks: change all *_conflict() functions to return bool. fs/locks: create a tree of dependent requests. locks: merge posix_unblock_lock() and locks_delete_block() VFS: locks: remove unnecessary white space. fs/cifs/file.c | 4 - fs/lockd/svclock.c | 2 fs/locks.c | 231 ++++++++++++++++++++++----------------- fs/nfs/nfs4proc.c | 6 + fs/nfsd/nfs4state.c | 6 + include/linux/fs.h | 11 +- include/trace/events/filelock.h | 16 +-- 7 files changed, 153 insertions(+), 123 deletions(-) -- Signature