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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD9EEC433F5 for ; Tue, 12 Oct 2021 15:14:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2EA260C4A for ; Tue, 12 Oct 2021 15:14:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235317AbhJLPQM (ORCPT ); Tue, 12 Oct 2021 11:16:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:32194 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229633AbhJLPQL (ORCPT ); Tue, 12 Oct 2021 11:16:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634051649; 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: in-reply-to:in-reply-to:references:references; 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charset=us-ascii Content-Disposition: inline In-Reply-To: <20211012150827.GB20571@lst.de> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Oct 12, 2021 at 05:08:27PM +0200, Christoph Hellwig wrote: > On Tue, Oct 12, 2021 at 11:06:51PM +0800, Ming Lei wrote: > > > We can get rid of the QUEUE_FLAG_QUIESCED flag now and just look > > > at ->quiesce_depth directly. > > > > I'd rather not to do that given we need to check QUEUE_FLAG_QUIESCED in fast > > path. > > Checking an integer vs checking a bit is easier actually faster or at > least the same speed depending on the architecture / micro architecture. ->queue_flag is always hot, but quiesce_depth can't be and shouldn't be since it is used very less. -- Ming 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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75434C433EF for ; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Oct 12, 2021 at 05:08:27PM +0200, Christoph Hellwig wrote: > On Tue, Oct 12, 2021 at 11:06:51PM +0800, Ming Lei wrote: > > > We can get rid of the QUEUE_FLAG_QUIESCED flag now and just look > > > at ->quiesce_depth directly. > > > > I'd rather not to do that given we need to check QUEUE_FLAG_QUIESCED in fast > > path. > > Checking an integer vs checking a bit is easier actually faster or at > least the same speed depending on the architecture / micro architecture. ->queue_flag is always hot, but quiesce_depth can't be and shouldn't be since it is used very less. -- Ming _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme