From patchwork Mon May 20 12:51:04 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Simmons X-Patchwork-Id: 10951053 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0CBA116C1 for ; Mon, 20 May 2019 12:52:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F067D28844 for ; Mon, 20 May 2019 12:52:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E4FC328795; Mon, 20 May 2019 12:52:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from pdx1-mailman02.dreamhost.com (pdx1-mailman02.dreamhost.com [64.90.62.194]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A06F826B39 for ; Mon, 20 May 2019 12:52:40 +0000 (UTC) Received: from pdx1-mailman02.dreamhost.com (localhost [IPv6:::1]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id 01B5B21FAE6; Mon, 20 May 2019 05:52:00 -0700 (PDT) X-Original-To: lustre-devel@lists.lustre.org Delivered-To: lustre-devel-lustre.org@pdx1-mailman02.dreamhost.com Received: from smtp4.ccs.ornl.gov (smtp4.ccs.ornl.gov [160.91.203.40]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id 5FA0B21F468 for ; Mon, 20 May 2019 05:51:22 -0700 (PDT) Received: from star.ccs.ornl.gov (star.ccs.ornl.gov [160.91.202.134]) by smtp4.ccs.ornl.gov (Postfix) with ESMTP id 86D241005243; Mon, 20 May 2019 08:51:13 -0400 (EDT) Received: by star.ccs.ornl.gov (Postfix, from userid 2004) id 85B4A2B7; Mon, 20 May 2019 08:51:13 -0400 (EDT) From: James Simmons To: Andreas Dilger , Oleg Drokin , NeilBrown Date: Mon, 20 May 2019 08:51:04 -0400 Message-Id: <1558356671-29599-23-git-send-email-jsimmons@infradead.org> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1558356671-29599-1-git-send-email-jsimmons@infradead.org> References: <1558356671-29599-1-git-send-email-jsimmons@infradead.org> Subject: [lustre-devel] [PATCH v2 22/29] lustre: portals_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" X-Virus-Scanned: ClamAV using ClamSMTP 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. Signed-off-by: NeilBrown --- 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 a4aeac8..d0fefcb 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 343d575..d9ab9ed 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)