From mboxrd@z Thu Jan 1 00:00:00 1970 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 C3C8CCE79CE for ; Wed, 20 Sep 2023 11:55:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234638AbjITLz2 (ORCPT ); Wed, 20 Sep 2023 07:55:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234834AbjITLz1 (ORCPT ); Wed, 20 Sep 2023 07:55:27 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9B4ED7 for ; Wed, 20 Sep 2023 04:55:20 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2BEFAC433CA; Wed, 20 Sep 2023 11:55:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695210920; bh=gyJo1wT2TvXs8kbyhTBBgu17yQ+hzKBHvPevIiS4f5I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DAeagGtHKG4nE81o8uwEtPyblZUx6HpB0+JLZwxTJqsOh6GZqKLjwgmno/8drMvWX qrz8quV8lEA35P5H+Oo+Lpuq0wzkYoRLvTw4NEv7TAIVDZtZTM+SWnYMDHmogoPWK0 Xg2pAKcO2dxSezdCtvvblT0DI+0qx1OV7jny37SM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zqiang , "Paul E. McKenney" , Sasha Levin Subject: [PATCH 6.1 006/139] rcuscale: Move rcu_scale_writer() schedule_timeout_uninterruptible() to _idle() Date: Wed, 20 Sep 2023 13:29:00 +0200 Message-ID: <20230920112835.810847954@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230920112835.549467415@linuxfoundation.org> References: <20230920112835.549467415@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zqiang [ Upstream commit e60c122a1614b4f65b29a7bef9d83b9fd30e937a ] The rcuscale.holdoff module parameter can be used to delay the start of rcu_scale_writer() kthread. However, the hung-task timeout will trigger when the timeout specified by rcuscale.holdoff is greater than hung_task_timeout_secs: runqemu kvm nographic slirp qemuparams="-smp 4 -m 2048M" bootparams="rcuscale.shutdown=0 rcuscale.holdoff=300" [ 247.071753] INFO: task rcu_scale_write:59 blocked for more than 122 seconds. [ 247.072529] Not tainted 6.4.0-rc1-00134-gb9ed6de8d4ff #7 [ 247.073400] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 247.074331] task:rcu_scale_write state:D stack:30144 pid:59 ppid:2 flags:0x00004000 [ 247.075346] Call Trace: [ 247.075660] [ 247.075965] __schedule+0x635/0x1280 [ 247.076448] ? __pfx___schedule+0x10/0x10 [ 247.076967] ? schedule_timeout+0x2dc/0x4d0 [ 247.077471] ? __pfx_lock_release+0x10/0x10 [ 247.078018] ? enqueue_timer+0xe2/0x220 [ 247.078522] schedule+0x84/0x120 [ 247.078957] schedule_timeout+0x2e1/0x4d0 [ 247.079447] ? __pfx_schedule_timeout+0x10/0x10 [ 247.080032] ? __pfx_rcu_scale_writer+0x10/0x10 [ 247.080591] ? __pfx_process_timeout+0x10/0x10 [ 247.081163] ? __pfx_sched_set_fifo_low+0x10/0x10 [ 247.081760] ? __pfx_rcu_scale_writer+0x10/0x10 [ 247.082287] rcu_scale_writer+0x6b1/0x7f0 [ 247.082773] ? mark_held_locks+0x29/0xa0 [ 247.083252] ? __pfx_rcu_scale_writer+0x10/0x10 [ 247.083865] ? __pfx_rcu_scale_writer+0x10/0x10 [ 247.084412] kthread+0x179/0x1c0 [ 247.084759] ? __pfx_kthread+0x10/0x10 [ 247.085098] ret_from_fork+0x2c/0x50 [ 247.085433] This commit therefore replaces schedule_timeout_uninterruptible() with schedule_timeout_idle(). Signed-off-by: Zqiang Signed-off-by: Paul E. McKenney Signed-off-by: Sasha Levin --- kernel/rcu/rcuscale.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c index 7854dc3226e1b..0b88d96511adc 100644 --- a/kernel/rcu/rcuscale.c +++ b/kernel/rcu/rcuscale.c @@ -423,7 +423,7 @@ rcu_scale_writer(void *arg) sched_set_fifo_low(current); if (holdoff) - schedule_timeout_uninterruptible(holdoff * HZ); + schedule_timeout_idle(holdoff * HZ); /* * Wait until rcu_end_inkernel_boot() is called for normal GP tests -- 2.40.1