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 X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CFA1C432BE for ; Mon, 16 Aug 2021 13:25:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3559963282 for ; Mon, 16 Aug 2021 13:25:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240463AbhHPN0Y (ORCPT ); Mon, 16 Aug 2021 09:26:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:37182 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239294AbhHPNQJ (ORCPT ); Mon, 16 Aug 2021 09:16:09 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D31166115A; Mon, 16 Aug 2021 13:12:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1629119573; bh=8RfsVLE/13D9ne70jDeXISXvLMSX+mhrYS90ZcUzqfk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y8DH9OdzhpFqPG6vPeRTHJtSJu1BhTLW4krrRNDb+7KJWi7yW1HyKE3jvwS+5tLNH k/voW2eIrBaAJACt9PMpsBCcXJgxmt0llRxRsGqNL0sDfwMDHzSLAZNHoDAVIng+WC PRjd20u6XdEO9gPGWEGWYpvyVRtj8T6SBCLB0qkY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hao Xu , Jens Axboe , Sasha Levin Subject: [PATCH 5.13 078/151] io-wq: fix bug of creating io-wokers unconditionally Date: Mon, 16 Aug 2021 15:01:48 +0200 Message-Id: <20210816125446.649235369@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210816125444.082226187@linuxfoundation.org> References: <20210816125444.082226187@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Hao Xu [ Upstream commit 49e7f0c789add1330b111af0b7caeb0e87df063e ] The former patch to add check between nr_workers and max_workers has a bug, which will cause unconditionally creating io-workers. That's because the result of the check doesn't affect the call of create_io_worker(), fix it by bringing in a boolean value for it. Fixes: 21698274da5b ("io-wq: fix lack of acct->nr_workers < acct->max_workers judgement") Signed-off-by: Hao Xu Link: https://lore.kernel.org/r/20210808135434.68667-2-haoxu@linux.alibaba.com [axboe: drop hunk that isn't strictly needed] Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- fs/io-wq.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/io-wq.c b/fs/io-wq.c index 77026d42cb79..2c8a9a394884 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -283,16 +283,24 @@ static void create_worker_cb(struct callback_head *cb) struct io_wq *wq; struct io_wqe *wqe; struct io_wqe_acct *acct; + bool do_create = false; cwd = container_of(cb, struct create_worker_data, work); wqe = cwd->wqe; wq = wqe->wq; acct = &wqe->acct[cwd->index]; raw_spin_lock_irq(&wqe->lock); - if (acct->nr_workers < acct->max_workers) + if (acct->nr_workers < acct->max_workers) { acct->nr_workers++; + do_create = true; + } raw_spin_unlock_irq(&wqe->lock); - create_io_worker(wq, cwd->wqe, cwd->index); + if (do_create) { + create_io_worker(wq, cwd->wqe, cwd->index); + } else { + atomic_dec(&acct->nr_running); + io_worker_ref_put(wq); + } kfree(cwd); } -- 2.30.2