From patchwork Tue Feb 19 00:09:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: NeilBrown X-Patchwork-Id: 10819101 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 899EE1399 for ; Tue, 19 Feb 2019 00:15:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 741E02B65E for ; Tue, 19 Feb 2019 00:15:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 614542BDE4; Tue, 19 Feb 2019 00:15:04 +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 0D9232B65E for ; Tue, 19 Feb 2019 00:15:04 +0000 (UTC) Received: from pdx1-mailman02.dreamhost.com (localhost [IPv6:::1]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id 713084E31E9; Mon, 18 Feb 2019 16:15:03 -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 3EDBF4E31B8 for ; Mon, 18 Feb 2019 16:15:01 -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 58649ACC1; Tue, 19 Feb 2019 00:15:00 +0000 (UTC) From: NeilBrown To: James Simmons , Andreas Dilger , Oleg Drokin Date: Tue, 19 Feb 2019 11:09:07 +1100 Message-ID: <155053494690.24125.10261783071575748633.stgit@noble.brown> In-Reply-To: <155053473693.24125.6976971762921761309.stgit@noble.brown> References: <155053473693.24125.6976971762921761309.stgit@noble.brown> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Subject: [lustre-devel] [PATCH 35/37] 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 17aee8ea63ac..d07b0a498bff 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; void *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 78c1ca52fc77..88a65a19785c 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, void *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)