From patchwork Wed Oct 19 22:51:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 13012453 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 2026CC433FE for ; Wed, 19 Oct 2022 22:51:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229644AbiJSWvm (ORCPT ); Wed, 19 Oct 2022 18:51:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51062 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229525AbiJSWvl (ORCPT ); Wed, 19 Oct 2022 18:51:41 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18F71F0347; Wed, 19 Oct 2022 15:51:41 -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 B8702B8260A; Wed, 19 Oct 2022 22:51:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6945FC433D6; Wed, 19 Oct 2022 22:51:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1666219898; bh=UST9akqGgKijeYQNO4FdueU2YnDxTO/0ttUDn2X6T0k=; h=Date:From:To:Cc:Subject:Reply-To:From; b=XRA5wehRbgkjjZI0HyFSLboyDaeS0AORi+2YzUGqE7fbtosJpSNcrFqZNLw4KImbc 0Ifjf/GfKGGvoTjr1SK+0cZ3UWtIqOWWhGnnjq3g+mc+19QKlREXdXjk0IFRT6GceS COGATVhSXmn0XowNFSYqQZNVSmnTmgnf4ydLNQLEMqyQLCvDsOyZQlWgebK+pb1WSr R50BkbxU1lJU6s95lKy751zOuKkr/dK8K/JEcsc4kcnylzLQaMPnAdACNnX+WLnMzT j/b/AoQ85gY/xNhEjMMStHDLYF7qyOcDUlns3N8TPnwzmEu0y2he7ApD+n6IJlZBbA Ruca7DChvaLBA== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 0ABE15C06B4; Wed, 19 Oct 2022 15:51:38 -0700 (PDT) Date: Wed, 19 Oct 2022 15:51:38 -0700 From: "Paul E. McKenney" To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, rostedt@goodmis.org Subject: [PATCH rcu 0/14] Lazy call_rcu() updates for v6.2 Message-ID: <20221019225138.GA2499943@paulmck-ThinkPad-P17-Gen-1> Reply-To: paulmck@kernel.org MIME-Version: 1.0 Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org Hello! This series provides energy efficiency for nearly-idle systems by making call_rcu() more lazy. Several NOCB changes come along for the ride: 1. Simplify rcu_init_nohz() cpumask handling, courtesy of Zhen Lei. 2. Fix late wakeup when flush of bypass cblist happens, courtesy of "Joel Fernandes (Google)". 3. Fix missing nocb gp wake on rcu_barrier(), courtesy of Frederic Weisbecker. 4. Make call_rcu() lazy to save power, courtesy of "Joel Fernandes (Google)". 5. Refactor code a bit in rcu_nocb_do_flush_bypass(), courtesy of "Joel Fernandes (Google)". 6. Shrinker for lazy rcu, courtesy of Vineeth Pillai. 7. Add laziness and kfree tests, courtesy of "Joel Fernandes (Google)". 8. percpu-refcount: Use call_rcu_flush() for atomic switch, courtesy of "Joel Fernandes (Google)". 9. Use call_rcu_flush() instead of call_rcu, courtesy of "Joel Fernandes (Google)". 10. Use call_rcu_flush() for async reader test, courtesy of "Joel Fernandes (Google)". 11. Use call_rcu_flush() where needed, courtesy of "Joel Fernandes (Google)". 12. scsi/scsi_error: Use call_rcu_flush() instead of call_rcu(), courtesy of Uladzislau Rezki. 13. Make queue_rcu_work() use call_rcu_flush(), courtesy of Uladzislau Rezki. 14. Use call_rcu_flush() instead of call_rcu(), courtesy of "Joel Fernandes (Google)". Thanx, Paul ------------------------------------------------------------------------ b/drivers/scsi/scsi_error.c | 2 b/include/linux/rcupdate.h | 9 + b/kernel/rcu/Kconfig | 8 + b/kernel/rcu/rcu.h | 8 + b/kernel/rcu/rcuscale.c | 68 +++++++++++- b/kernel/rcu/rcutorture.c | 16 +- b/kernel/rcu/sync.c | 2 b/kernel/rcu/tiny.c | 2 b/kernel/rcu/tree.c | 11 + b/kernel/rcu/tree.h | 1 b/kernel/rcu/tree_exp.h | 2 b/kernel/rcu/tree_nocb.h | 34 +----- b/kernel/workqueue.c | 2 b/lib/percpu-refcount.c | 3 b/net/rxrpc/conn_object.c | 2 kernel/rcu/rcuscale.c | 2 kernel/rcu/tree.c | 129 +++++++++++++++-------- kernel/rcu/tree.h | 11 + kernel/rcu/tree_nocb.h | 243 ++++++++++++++++++++++++++++++++++++-------- 19 files changed, 424 insertions(+), 131 deletions(-)