From nobody Sun Apr 12 00:29:54 2026 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 36E81C19F2B for ; Thu, 4 Aug 2022 08:42:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239539AbiHDImJ (ORCPT ); Thu, 4 Aug 2022 04:42:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239386AbiHDIlp (ORCPT ); Thu, 4 Aug 2022 04:41:45 -0400 Received: from mail-pl1-x635.google.com (mail-pl1-x635.google.com [IPv6:2607:f8b0:4864:20::635]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0623A66125 for ; Thu, 4 Aug 2022 01:41:03 -0700 (PDT) Received: by mail-pl1-x635.google.com with SMTP id w14so5668983plp.9 for ; Thu, 04 Aug 2022 01:41:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc; bh=JYtx0gSEzUyP9tNNW1dyx5vOU7phI7IefN54Dq4Qn2I=; b=nPH69jq36PE5OSDqSsRcVNcq3kxLmc0zvtGfIflRk9S3woqyXqCymAOCoLVA80yOAv RRxjrJpwbytrD3aB12lEra/NWYQ/GSZGYdbm6tbMl3hS5cQS8mPJX5YK56zjt7hZhUTD 3HmDvXLtBv9/QWCxGv4CNz9rwUlPE/t7wxXUY9a7muEOO1/ysTqB9PETUCQjn9QjaxDS 7VIU8hYOz4sx6TceGzZxffzuOw7I1cw4CwrXG71pEo1EgrVMtldTuyFKfQpf86BCoxBn 6zlXds1v8kBDQGQ5RB+VCF1VzdpbkK3N75b7hgnH+FeNZjDWm8FJrE4C5jDie80AA1Nc h5UQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc; bh=JYtx0gSEzUyP9tNNW1dyx5vOU7phI7IefN54Dq4Qn2I=; b=l2+1HmGqSJSkrRocXX8yE3lue0x0s7QGt2Hk85sBIvZ0Oy5xDhvzqgpITFhoa0uQ/K 0xJ6gV6WppCANKDxz005ewtikOGma4H/o7PFDKHmn95s+nqLLgZ35GUGFiT4+WpCgOp2 Wm/9a9GC7C5HFgVZCyFXKz75tcRqxwlwShYwEW7++ywYhrE8d6rBeBPaISYC/8zp16xZ vupUVDhqXZMr9LSka6K2wyn1RiagMaMZyNiDEAsiS4+m747/RLKQMyGqkhLM0jz9TQxX e2U4BCsgYAw1dOlIoMJCCYtq7I/dSwSaGGY1SZO0TGSbqnD09kphWEUYbOESaA+idHjh Mk3Q== X-Gm-Message-State: ACgBeo0Wl5J5OPyApcpvKdwhq9nTm34T1yRAeN0uopDffA6m2MqF4p6R PSeNrZc2gx3dKkY9aDUQ1qnMenIutYI= X-Google-Smtp-Source: AA6agR5VwKqCPDcRPZSLIdxQMKZkjNmhgeyswq844jixfkWUVrC/JiSV5Mt6SMfvDmSeXyKUnLfCaA== X-Received: by 2002:a17:902:ac97:b0:16e:eb08:fb15 with SMTP id h23-20020a170902ac9700b0016eeb08fb15mr941051plr.7.1659602462293; Thu, 04 Aug 2022 01:41:02 -0700 (PDT) Received: from localhost ([47.89.225.180]) by smtp.gmail.com with ESMTPSA id b27-20020aa78edb000000b0052b6277df9esm354103pfr.43.2022.08.04.01.41.01 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 04 Aug 2022 01:41:01 -0700 (PDT) From: Lai Jiangshan To: linux-kernel@vger.kernel.org Cc: Lai Jiangshan , Tejun Heo , Lai Jiangshan Subject: [RFC PATCH 6/8] workqueue: Simplify the starting of the newly created worker Date: Thu, 4 Aug 2022 16:41:33 +0800 Message-Id: <20220804084135.92425-7-jiangshanlai@gmail.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20220804084135.92425-1-jiangshanlai@gmail.com> References: <20220804084135.92425-1-jiangshanlai@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Lai Jiangshan There is no point for the newly created worker entering and leaving idle in the same pool->lock held region and checking WORKER_DIE because it has not added to idle_list before the lock. Avoid the code in the starting of the newly created worker and move those code to the end of the worker_thread(). Signed-off-by: Lai Jiangshan --- kernel/workqueue.c | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index afe62649fb3a..64dc1833d11a 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -2383,31 +2383,16 @@ static int worker_thread(void *__worker) =20 raw_spin_lock_irq(&pool->lock); worker->pool->nr_workers++; - worker_enter_idle(worker); complete(&pool->created); -woke_up: - - /* am I supposed to die? */ - if (unlikely(worker->flags & WORKER_DIE)) { - raw_spin_unlock_irq(&pool->lock); - WARN_ON_ONCE(!list_empty(&worker->entry)); - - set_task_comm(worker->task, "kworker/dying"); - ida_free(&pool->worker_ida, worker->id); - worker_detach_from_pool(worker); - kfree(worker); - return 0; - } =20 - worker_leave_idle(worker); -recheck: +loop: /* no more worker necessary? */ if (!need_more_worker(pool)) goto sleep; =20 /* do we need to manage? */ if (unlikely(!may_start_working(pool)) && manage_workers(worker)) - goto recheck; + goto loop; =20 /* * ->scheduled list can only be filled while a worker is @@ -2457,7 +2442,21 @@ static int worker_thread(void *__worker) raw_spin_unlock_irq(&pool->lock); schedule(); raw_spin_lock_irq(&pool->lock); - goto woke_up; + + /* am I supposed to die? */ + if (unlikely(worker->flags & WORKER_DIE)) { + raw_spin_unlock_irq(&pool->lock); + WARN_ON_ONCE(!list_empty(&worker->entry)); + + set_task_comm(worker->task, "kworker/dying"); + ida_free(&pool->worker_ida, worker->id); + worker_detach_from_pool(worker); + kfree(worker); + return 0; + } + + worker_leave_idle(worker); + goto loop; } =20 /** --=20 2.19.1.6.gb485710b