From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CD85D208D7; Fri, 27 Sep 2024 07:45:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727423124; cv=none; b=fQL3kYhOmtGFK3JYlIQ/RoF5H8cvdb6/gEutJS5+XOGy/qleiKnrAEetJNBQZkJ+Eam4CHvePOpx6B5lAscvMfZkbhX3Np61eHFaRTiynZpqSEI+SrhiJn26SJRHpZxLVOF+moATuk3JkdxnIybUa4B/i0ChUEAP69AudwMH4fA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727423124; c=relaxed/simple; bh=ypXZmQ6dKOwdo+1jgOYy9lN6chCL2pA6F1O+NZ0qugw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=lMGMrtbOFfycq6vGM1mBxV9N1Jf5vH6FlinGGsyXRMfyw1Pvl7YzwuZmnwD9O96jXX/w/tr5tSldoI4WQklHR88O+cutMWaCDURHn1R1c3z93+8vx5gajnpbnwtGOa63S61NOGaJ891zW9cG3/pXsPa/yBReXTD8kbJOcjIil0o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4XFMv02XGFz4f3jJ1; Fri, 27 Sep 2024 15:45:00 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.252]) by mail.maildlp.com (Postfix) with ESMTP id A72791A0D44; Fri, 27 Sep 2024 15:45:16 +0800 (CST) Received: from [10.67.109.79] (unknown [10.67.109.79]) by APP3 (Coremail) with SMTP id _Ch0CgCH24eLYvZmVXyTCQ--.18822S2; Fri, 27 Sep 2024 15:45:16 +0800 (CST) Message-ID: Date: Fri, 27 Sep 2024 15:45:15 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 1/3] cgroup/bpf: use a dedicated workqueue for cgroup bpf destruction To: =?UTF-8?Q?Michal_Koutn=C3=BD?= Cc: tj@kernel.org, lizefan.x@bytedance.com, hannes@cmpxchg.org, longman@redhat.com, chenridong@huawei.com, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org References: <20240923114352.4001560-1-chenridong@huaweicloud.com> <20240923114352.4001560-2-chenridong@huaweicloud.com> <24rp7n32rtzdszc7zxwmeitfmtib5yu7wo432b7uxjkvbdtrxp@kemt7l74yich> Content-Language: en-US From: Chen Ridong In-Reply-To: <24rp7n32rtzdszc7zxwmeitfmtib5yu7wo432b7uxjkvbdtrxp@kemt7l74yich> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CM-TRANSID:_Ch0CgCH24eLYvZmVXyTCQ--.18822S2 X-Coremail-Antispam: 1UD129KBjvdXoWrZw1fWF1fGryxCF4kGFWrGrg_yoWfZrb_Wa yIkwn2k3yrCay2gw1Iq39xXrWkCF48JryUWwn5Gr47Gw1fWw4DWa97Jrn3Za4UZa1vyasr uFZxWa42qr129jkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbwkYFVCjjxCrM7AC8VAFwI0_Gr0_Xr1l1xkIjI8I6I8E6xAIw20E Y4v20xvaj40_Wr0E3s1l1IIY67AEw4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwV A0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x02 67AKxVWxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxV AFwI0_GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2 j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7x kEbVWUJVW8JwACjcxG0xvEwIxGrwCY1x0262kKe7AKxVWUAVWUtwCF04k20xvY0x0EwIxG rwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4 vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IY x2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Jr0_Gr1lIxAIcVCF04k26c xKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAF wI0_Jr0_GrUvcSsGvfC2KfnxnUUI43ZEXa7IU1veHDUUUUU== X-CM-SenderInfo: hfkh02xlgr0w46kxt4xhlfz01xgou0bp/ On 2024/9/26 20:49, Michal Koutný wrote: > Hello. > > On Mon, Sep 23, 2024 at 11:43:50AM GMT, Chen Ridong wrote: >> +static int __init cgroup_bpf_wq_init(void) >> +{ >> + cgroup_bpf_destroy_wq = alloc_workqueue("cgroup_bpf_destroy", 0, 1); >> + WARN_ON_ONCE(!cgroup_bpf_destroy_wq); >> + return 0; >> +} >> +core_initcall(cgroup_bpf_wq_init); > > I think hard fail (panic() if you want to avoid BUG_ON) would be > warranted here and mere warning would leave system exposed to worse > errors later (and _ONCE in an initcall looks unnecessary). > Thank you. I think panic() is alright. Best regards, Ridong > Maybe look at other global wqs. I see that returning -ENOMEM might be an > option, however, I don't see that initcall's return value would be > processed anywhere currently :-/ > > Besides this allocation failpath this is a sensible change to me. > > Thanks, > Michal