From patchwork Thu Jun 2 13:35:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Waiman Long X-Patchwork-Id: 12867873 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 C73BAC43334 for ; Thu, 2 Jun 2022 13:36:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235421AbiFBNf7 (ORCPT ); Thu, 2 Jun 2022 09:35:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234219AbiFBNf5 (ORCPT ); Thu, 2 Jun 2022 09:35:57 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 006446C57A for ; Thu, 2 Jun 2022 06:35:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1654176956; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nIFIquhWxRW8zi5j5Mk86JmeILvcLaTEEhtXEaVuk6Y=; b=NRlfiKmLt790STaLwm29z5ceYJieJ2R+lvwu1polF39QbGM/yIntolBkr31d5ncOcFU4FM qqkAnLStA+qi03bAKOyORE7idI75NE0eKbSc+GOUv5FczYNCcYkMgUibiuPcsMwYUTrd0i k2N5aB4fX+dKHjVCUQh9BCCEjY8hf+I= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-264-wyNoR1d5PEaXsdclR8ldVg-1; Thu, 02 Jun 2022 09:35:53 -0400 X-MC-Unique: wyNoR1d5PEaXsdclR8ldVg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 81A21811E75; Thu, 2 Jun 2022 13:35:52 +0000 (UTC) Received: from llong.com (unknown [10.22.32.147]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3BC8E2166B26; Thu, 2 Jun 2022 13:35:52 +0000 (UTC) From: Waiman Long To: Tejun Heo , Jens Axboe Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Ming Lei , Waiman Long Subject: [PATCH v5 2/3] blk-cgroup: Return -ENOMEM directly in blkcg_css_alloc() error path Date: Thu, 2 Jun 2022 09:35:42 -0400 Message-Id: <20220602133543.128088-3-longman@redhat.com> In-Reply-To: <20220601211824.89626-1-longman@redhat.com> References: <20220601211824.89626-1-longman@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org For blkcg_css_alloc(), the only error that will be returned is -ENOMEM. Simplify error handling code by returning this error directly instead of setting an intermediate "ret" variable. Signed-off-by: Waiman Long Acked-by: Tejun Heo --- block/blk-cgroup.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index acd9b0aa8dc8..9021f75fc752 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1177,7 +1177,6 @@ static struct cgroup_subsys_state * blkcg_css_alloc(struct cgroup_subsys_state *parent_css) { struct blkcg *blkcg; - struct cgroup_subsys_state *ret; int i; mutex_lock(&blkcg_pol_mutex); @@ -1186,10 +1185,8 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) blkcg = &blkcg_root; } else { blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); - if (!blkcg) { - ret = ERR_PTR(-ENOMEM); + if (!blkcg) goto unlock; - } } for (i = 0; i < BLKCG_MAX_POLS ; i++) { @@ -1206,10 +1203,9 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) continue; cpd = pol->cpd_alloc_fn(GFP_KERNEL); - if (!cpd) { - ret = ERR_PTR(-ENOMEM); + if (!cpd) goto free_pd_blkcg; - } + blkcg->cpd[i] = cpd; cpd->blkcg = blkcg; cpd->plid = i; @@ -1238,7 +1234,7 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) kfree(blkcg); unlock: mutex_unlock(&blkcg_pol_mutex); - return ret; + return ERR_PTR(-ENOMEM); } static int blkcg_css_online(struct cgroup_subsys_state *css)