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[23.128.96.18]) by mx.google.com with ESMTP id c14si2067464edv.132.2021.01.21.04.26.52; Thu, 21 Jan 2021 04:27:16 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=ENZwl9a9; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730332AbhAUMXi (ORCPT + 99 others); Thu, 21 Jan 2021 07:23:38 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:47538 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728078AbhAUMWs (ORCPT ); Thu, 21 Jan 2021 07:22:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611231681; 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=EdNOWiSvpp1h1FQ1yCUgYu+uACMYKqVEBGPORZ+jdtY=; b=ENZwl9a9rUiP+YnNq7bBmZY/LFIX7XeFyWQ09bhL9wItUXHtzLR83RfY6EypqomYlFawxo glY4JSA57ancEw7ZuufcsJRy2sRlFuVKq1krd/Z2L9PiVdaTEh5QwP/dbrJhBJ6zWCkpPl sb15Q2B2mgmUP1nBJzjQKzB/TxUt1sY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-538-gVia8A6FOX638Qz587PhRw-1; Thu, 21 Jan 2021 07:21:19 -0500 X-MC-Unique: gVia8A6FOX638Qz587PhRw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EAD628144E0; Thu, 21 Jan 2021 12:21:17 +0000 (UTC) Received: from [10.72.12.73] (ovpn-12-73.pek2.redhat.com [10.72.12.73]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9DB4060BF3; Thu, 21 Jan 2021 12:21:15 +0000 (UTC) Subject: Re: [PATCH 1/2 v2] dma-iommu: use static-key to minimize the impact in the fast-path To: Christoph Hellwig Cc: linux-kernel@vger.kernel.org, thomas.lendacky@amd.com, will@kernel.org, iommu@lists.linux-foundation.org, robin.murphy@arm.com References: <20210119111616.12761-1-lijiang@redhat.com> <20210119111616.12761-2-lijiang@redhat.com> <20210119152641.GA3453587@infradead.org> From: lijiang Message-ID: Date: Thu, 21 Jan 2021 20:21:12 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20210119152641.GA3453587@infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Christoph Thanks for the comment. 在 2021年01月19日 23:26, Christoph Hellwig 写道: > On Tue, Jan 19, 2021 at 07:16:15PM +0800, Lianbo Jiang wrote: >> +static DEFINE_STATIC_KEY_FALSE(__deferred_attach); > Why the strange underscores? Wouldn't iommu_deferred_attach_enabled The variable is defined with the static keyword, which indicates that the variable is only used in the local module(file), and gives a hint explicitly with the underscore prefix. Anyway, this is my personal opinion. > be a better name? > It could be a long name? Thanks. Lianbo