From patchwork Mon Mar 4 06:31:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: NeilBrown X-Patchwork-Id: 10837363 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 0E6591399 for ; Mon, 4 Mar 2019 06:35:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EA45B289BC for ; Mon, 4 Mar 2019 06:35:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D8B9B29D79; Mon, 4 Mar 2019 06:35:10 +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 553D0289BC for ; Mon, 4 Mar 2019 06:35:10 +0000 (UTC) Received: from pdx1-mailman02.dreamhost.com (localhost [IPv6:::1]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id 1F5266828D5; Sun, 3 Mar 2019 22:35:10 -0800 (PST) X-Original-To: lustre-devel@lists.lustre.org Delivered-To: lustre-devel-lustre.org@pdx1-mailman02.dreamhost.com Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id 67CAF6827E8 for ; Sun, 3 Mar 2019 22:35:08 -0800 (PST) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 8804DAC9C; Mon, 4 Mar 2019 06:35:07 +0000 (UTC) From: NeilBrown To: Andreas Dilger , James Simmons , Oleg Drokin Date: Mon, 04 Mar 2019 17:31:38 +1100 Message-ID: <155168109869.31333.7012632326385947412.stgit@noble.brown> In-Reply-To: <155168107971.31333.14345309795939467246.stgit@noble.brown> References: <155168107971.31333.14345309795939467246.stgit@noble.brown> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Subject: [lustre-devel] [PATCH 17/28] 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 Errors-To: lustre-devel-bounces@lists.lustre.org Sender: "lustre-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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 and increasingly irrelevant comment in the declaration of struct portals_handle. Signed-off-by: NeilBrown --- .../staging/lustre/lustre/include/lustre_handles.h | 3 --- .../lustre/lustre/obdclass/lustre_handles.c | 7 ------- 2 files changed, 10 deletions(-) diff --git a/drivers/staging/lustre/lustre/include/lustre_handles.h b/drivers/staging/lustre/lustre/include/lustre_handles.h index cc433f48d367..ef3a6ec55403 100644 --- a/drivers/staging/lustre/lustre/include/lustre_handles.h +++ b/drivers/staging/lustre/lustre/include/lustre_handles.h @@ -62,10 +62,7 @@ struct portals_handle { u64 h_cookie; 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/drivers/staging/lustre/lustre/obdclass/lustre_handles.c b/drivers/staging/lustre/lustre/obdclass/lustre_handles.c index 72de668c879b..c6e0ca3ddf3a 100644 --- a/drivers/staging/lustre/lustre/obdclass/lustre_handles.c +++ b/drivers/staging/lustre/lustre/obdclass/lustre_handles.c @@ -85,7 +85,6 @@ void class_handle_hash(struct portals_handle *h, 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)