From patchwork Fri Mar 24 00:19:37 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: 13186201 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 19912C74A5B for ; Fri, 24 Mar 2023 00:20:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231359AbjCXAUI (ORCPT ); Thu, 23 Mar 2023 20:20:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231355AbjCXAT7 (ORCPT ); Thu, 23 Mar 2023 20:19:59 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0994A2E0E3; Thu, 23 Mar 2023 17:19:51 -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 E0F84B822B8; Fri, 24 Mar 2023 00:19:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC604C433B3; Fri, 24 Mar 2023 00:19:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679617181; bh=n01ySLfbpYhus3Mob79To2m1LPQToRsdp4kgb/5Hf30=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VLuPzNlCYuKg3TaBy/0difG1UhzPlTqt2rEuEtkPtyAaxZU3H0ZuprO6BsoMhLNyO JgmqxDdZPk1h4spbzVRTjjafiVD1bpQgETQMit9Yq/zxc38SrF0/L00TowiAQynwZG pZBIR5nIrrraXyhU6ix/xtC7+oNqcPvAOzaIr93nZoPw8xy7d3BpvRcqo7oZtUkU8k fG14zhuZxOjNsVd+iJ79V6TqA9+K2z4M+pAEjR777LowwZfgJs66XvQGKX0po4GDmz vvGqZfamClj6Hm6Yndi+TOlCftlntgYK8FFRMYfOppX2GpaDvFmjRchmttFNv30oU4 KSVTmaCeasItA== Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id C78F315403AB; Thu, 23 Mar 2023 17:19:40 -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" Subject: [PATCH RFC rcu 18/19] srcu: Fix long lines in srcu_funnel_gp_start() Date: Thu, 23 Mar 2023 17:19:37 -0700 Message-Id: <20230324001938.3443499-18-paulmck@kernel.org> X-Mailer: git-send-email 2.40.0.rc2 In-Reply-To: <3db82572-f156-4a5d-b711-841aa28bd996@paulmck-laptop> References: <3db82572-f156-4a5d-b711-841aa28bd996@paulmck-laptop> 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. Signed-off-by: Paul E. McKenney Cc: Christoph Hellwig --- 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 fcb2bac7bb4b..61dd47981b40 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); } /*