From patchwork Thu Feb 27 21:18:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Simmons X-Patchwork-Id: 11410851 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 998361580 for ; Thu, 27 Feb 2020 21:48:21 +0000 (UTC) Received: from pdx1-mailman02.dreamhost.com (pdx1-mailman02.dreamhost.com [64.90.62.194]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 81D7C24690 for ; Thu, 27 Feb 2020 21:48:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 81D7C24690 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lustre-devel-bounces@lists.lustre.org Received: from pdx1-mailman02.dreamhost.com (localhost [IPv6:::1]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id CA39034A3ED; Thu, 27 Feb 2020 13:38:34 -0800 (PST) X-Original-To: lustre-devel@lists.lustre.org Delivered-To: lustre-devel-lustre.org@pdx1-mailman02.dreamhost.com Received: from smtp3.ccs.ornl.gov (smtp3.ccs.ornl.gov [160.91.203.39]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id 9278721FDDE for ; Thu, 27 Feb 2020 13:21:32 -0800 (PST) Received: from star.ccs.ornl.gov (star.ccs.ornl.gov [160.91.202.134]) by smtp3.ccs.ornl.gov (Postfix) with ESMTP id 8CFA0A167; Thu, 27 Feb 2020 16:18:20 -0500 (EST) Received: by star.ccs.ornl.gov (Postfix, from userid 2004) id 8B6E047C; Thu, 27 Feb 2020 16:18:20 -0500 (EST) From: James Simmons To: Andreas Dilger , Oleg Drokin , NeilBrown Date: Thu, 27 Feb 2020 16:18:08 -0500 Message-Id: <1582838290-17243-621-git-send-email-jsimmons@infradead.org> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> References: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> Subject: [lustre-devel] [PATCH 620/622] lustre: handle: discard h_lock. X-BeenThere: lustre-devel@lists.lustre.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "For discussing Lustre software development." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lustre Development List MIME-Version: 1.0 Errors-To: lustre-devel-bounces@lists.lustre.org Sender: "lustre-devel" From: NeilBrown The h_lock spinlock is now only taken while bucket->lock is held. As a handle is associated with precisely one bucket, this means that h_lock can never be contended, so it isn't needed. So discard h_lock. Also discard an increasingly irrelevant comment in the declaration of struct portals_handle. WC-bug-id: https://jira.whamcloud.com/browse/LU-12542 Lustre-commit: 6acafe7ac4ef ("LU-12542 handle: discard h_lock.") Signed-off-by: NeilBrown Reviewed-on: https://review.whamcloud.com/35863 Reviewed-by: Neil Brown Reviewed-by: Shaun Tancheff Reviewed-by: Oleg Drokin Signed-off-by: James Simmons --- fs/lustre/include/lustre_handles.h | 3 --- fs/lustre/obdclass/lustre_handles.c | 7 ------- 2 files changed, 10 deletions(-) diff --git a/fs/lustre/include/lustre_handles.h b/fs/lustre/include/lustre_handles.h index afdade7..9dbe7c9 100644 --- a/fs/lustre/include/lustre_handles.h +++ b/fs/lustre/include/lustre_handles.h @@ -62,10 +62,7 @@ struct portals_handle { u64 h_cookie; const char *h_owner; refcount_t h_ref; - - /* newly added fields to handle the RCU issue. -jxiong */ struct rcu_head h_rcu; - spinlock_t h_lock; }; /* handles.c */ diff --git a/fs/lustre/obdclass/lustre_handles.c b/fs/lustre/obdclass/lustre_handles.c index 0048036..7ecd15ad3 100644 --- a/fs/lustre/obdclass/lustre_handles.c +++ b/fs/lustre/obdclass/lustre_handles.c @@ -85,7 +85,6 @@ void class_handle_hash(struct portals_handle *h, const char *owner) spin_unlock(&handle_base_lock); h->h_owner = owner; - spin_lock_init(&h->h_lock); bucket = &handle_hash[h->h_cookie & HANDLE_HASH_MASK]; spin_lock(&bucket->lock); @@ -108,13 +107,7 @@ static void class_handle_unhash_nolock(struct portals_handle *h) CDEBUG(D_INFO, "removing object %p with handle %#llx from hash\n", h, h->h_cookie); - spin_lock(&h->h_lock); - if (hlist_unhashed(&h->h_link)) { - spin_unlock(&h->h_lock); - return; - } hlist_del_init_rcu(&h->h_link); - spin_unlock(&h->h_lock); } void class_handle_unhash(struct portals_handle *h)