From patchwork Thu Mar 30 22:47:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 13195013 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 493C2C7619A for ; Thu, 30 Mar 2023 22:49:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231295AbjC3WtK (ORCPT ); Thu, 30 Mar 2023 18:49:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231304AbjC3WsJ (ORCPT ); Thu, 30 Mar 2023 18:48:09 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E81CC9; Thu, 30 Mar 2023 15:47:55 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 2367FB82A6B; Thu, 30 Mar 2023 22:47:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DAA3C43443; Thu, 30 Mar 2023 22:47:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680216449; bh=BGO1b8NtiaH39dX3EQtGPIpQm+szueNs/o3Qv7qj9XA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EP5v8NQwsl9ACrUnDx4NiTZkfRkpW82qKELLxm3Pdd7z0UWzwHj4lH6tR42X+x9LG o0E/uBm2C7vdQb8qqr783QZzmNpYbXE03RR3y/9OIS8xfFymHzTILRHzhd/MwPLdiU pD/OFqORgvpskQJSpzUEBL3c/6pPrC7w764TYJCmv1DtJVaW2yW2hmGnvMZfY4L3Uc P/nW4FeKWnewhFXrM2spAP2n01pBbjDC0nnWu6wvv2t5TqYtRqBQTUHOYwcZ72rDqp 20RThlRYEBWEZfqo2d8bdWqhAPPKTUNrSYqFCtfdZrqT0XEV5RYy97RklVV3QSNKwL Xvt8i18ezgpDg== Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id 418C41540490; Thu, 30 Mar 2023 15:47:28 -0700 (PDT) From: "Paul E. McKenney" To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org, hch@lst.de, "Paul E. McKenney" , Sachin Sant , "Zhang, Qiang1" Subject: [PATCH rcu 20/20] srcu: Fix long lines in srcu_funnel_gp_start() Date: Thu, 30 Mar 2023 15:47:26 -0700 Message-Id: <20230330224726.662344-20-paulmck@kernel.org> X-Mailer: git-send-email 2.40.0.rc2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org This commit creates an srcu_usage pointer named "sup" as a shorter synonym for the "ssp->srcu_sup" that was bloating several lines of code. Cc: Christoph Hellwig Tested-by: Sachin Sant Tested-by: "Zhang, Qiang1" Signed-off-by: Paul E. McKenney --- kernel/rcu/srcutree.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index f661a0f6bc0d..a887cfc89894 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -1004,9 +1004,10 @@ static void srcu_funnel_gp_start(struct srcu_struct *ssp, struct srcu_data *sdp, struct srcu_node *snp; struct srcu_node *snp_leaf; unsigned long snp_seq; + struct srcu_usage *sup = ssp->srcu_sup; /* Ensure that snp node tree is fully initialized before traversing it */ - if (smp_load_acquire(&ssp->srcu_sup->srcu_size_state) < SRCU_SIZE_WAIT_BARRIER) + if (smp_load_acquire(&sup->srcu_size_state) < SRCU_SIZE_WAIT_BARRIER) snp_leaf = NULL; else snp_leaf = sdp->mynode; @@ -1014,7 +1015,7 @@ static void srcu_funnel_gp_start(struct srcu_struct *ssp, struct srcu_data *sdp, if (snp_leaf) /* Each pass through the loop does one level of the srcu_node tree. */ for (snp = snp_leaf; snp != NULL; snp = snp->srcu_parent) { - if (WARN_ON_ONCE(rcu_seq_done(&ssp->srcu_sup->srcu_gp_seq, s)) && snp != snp_leaf) + if (WARN_ON_ONCE(rcu_seq_done(&sup->srcu_gp_seq, s)) && snp != snp_leaf) return; /* GP already done and CBs recorded. */ spin_lock_irqsave_rcu_node(snp, flags); snp_seq = snp->srcu_have_cbs[idx]; @@ -1041,20 +1042,20 @@ static void srcu_funnel_gp_start(struct srcu_struct *ssp, struct srcu_data *sdp, /* Top of tree, must ensure the grace period will be started. */ spin_lock_irqsave_ssp_contention(ssp, &flags); - if (ULONG_CMP_LT(ssp->srcu_sup->srcu_gp_seq_needed, s)) { + if (ULONG_CMP_LT(sup->srcu_gp_seq_needed, s)) { /* * Record need for grace period s. Pair with load * acquire setting up for initialization. */ - smp_store_release(&ssp->srcu_sup->srcu_gp_seq_needed, s); /*^^^*/ + smp_store_release(&sup->srcu_gp_seq_needed, s); /*^^^*/ } - if (!do_norm && ULONG_CMP_LT(ssp->srcu_sup->srcu_gp_seq_needed_exp, s)) - WRITE_ONCE(ssp->srcu_sup->srcu_gp_seq_needed_exp, s); + if (!do_norm && ULONG_CMP_LT(sup->srcu_gp_seq_needed_exp, s)) + WRITE_ONCE(sup->srcu_gp_seq_needed_exp, s); /* If grace period not already in progress, start it. */ - if (!WARN_ON_ONCE(rcu_seq_done(&ssp->srcu_sup->srcu_gp_seq, s)) && - rcu_seq_state(ssp->srcu_sup->srcu_gp_seq) == SRCU_STATE_IDLE) { - WARN_ON_ONCE(ULONG_CMP_GE(ssp->srcu_sup->srcu_gp_seq, ssp->srcu_sup->srcu_gp_seq_needed)); + if (!WARN_ON_ONCE(rcu_seq_done(&sup->srcu_gp_seq, s)) && + rcu_seq_state(sup->srcu_gp_seq) == SRCU_STATE_IDLE) { + WARN_ON_ONCE(ULONG_CMP_GE(sup->srcu_gp_seq, sup->srcu_gp_seq_needed)); srcu_gp_start(ssp); // And how can that list_add() in the "else" clause @@ -1063,12 +1064,12 @@ static void srcu_funnel_gp_start(struct srcu_struct *ssp, struct srcu_data *sdp, // can only be executed during early boot when there is only // the one boot CPU running with interrupts still disabled. if (likely(srcu_init_done)) - queue_delayed_work(rcu_gp_wq, &ssp->srcu_sup->work, + queue_delayed_work(rcu_gp_wq, &sup->work, !!srcu_get_delay(ssp)); - else if (list_empty(&ssp->srcu_sup->work.work.entry)) - list_add(&ssp->srcu_sup->work.work.entry, &srcu_boot_list); + else if (list_empty(&sup->work.work.entry)) + list_add(&sup->work.work.entry, &srcu_boot_list); } - spin_unlock_irqrestore_rcu_node(ssp->srcu_sup, flags); + spin_unlock_irqrestore_rcu_node(sup, flags); } /*