From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 2321E5FEED for ; Sun, 6 Oct 2024 03:55:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728186925; cv=none; b=lDjTUgZLzj5hV9rD8vkG5W3KmNKyGcaepvb7HiMrpDHXPulwsoJonaVypQv1Uocluj7qpGwa/wZnlsAOmAFddIl7tLfczcXItUV7FLr9ZmdtuXMNPbbFUr5Sx94zP947pjZZC62QLvtYCMFNN6XbA6n8Mnhc3TiyBeEup2aplYE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728186925; c=relaxed/simple; bh=cHzYy/peCHbekEClQEQlfrfvaaKGeLEEElmDPiw1bC8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=A6e5PAP+HOrsSpWxnUbb1cr7Hn9U49fQUruaubnZufYZlvRWiyl1W7YoGLLGZy9zoNmsuv15OGIJStHddwLmR4lAiOCloZEv9mwykiA5KaHQg28ESfV/xjC0IUT/uwaDC3kWxxjReqAbwd0p2bUVs7OhFP05TSadtlBw0NtqTsI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Hf2EooGD; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Hf2EooGD" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1728186919; 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; bh=7kLinepcpe1b0ntnO9Z6uP9P9sY4ikJtKhQzk/NG7UM=; b=Hf2EooGDMNfqOdgKrSD2GNIWH9IH2K7zP/SUEa8I4XhP5jBq7CUVy1DFAh+WFB1JXOPy6V vL92xBlwE+61Nk6eJDCTzOCjCDSGZk2EYrOMY5kFBBVgSuc8gaFbNGQa61ZYCHuqJ2ScxR +ChfjBeCkSeoZUZuBw4DGg3aGIzdByI= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-466-dAdgM1NMOdWw0pPn8FsyEw-1; Sat, 05 Oct 2024 23:55:15 -0400 X-MC-Unique: dAdgM1NMOdWw0pPn8FsyEw-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 46E17195422B; Sun, 6 Oct 2024 03:55:14 +0000 (UTC) Received: from fedora (unknown [10.72.116.21]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id DEB0E3000198; Sun, 6 Oct 2024 03:55:08 +0000 (UTC) Date: Sun, 6 Oct 2024 11:54:57 +0800 From: Ming Lei To: Pavel Begunkov Cc: Jens Axboe , io-uring@vger.kernel.org, linux-block@vger.kernel.org Subject: Re: [PATCH V6 5/8] io_uring: support sqe group with members depending on leader Message-ID: References: <20240912104933.1875409-1-ming.lei@redhat.com> <20240912104933.1875409-6-ming.lei@redhat.com> <36b88a5a-1209-4db3-8514-0f1e1828f7e1@gmail.com> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <36b88a5a-1209-4db3-8514-0f1e1828f7e1@gmail.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 On Fri, Oct 04, 2024 at 02:18:13PM +0100, Pavel Begunkov wrote: > On 9/12/24 11:49, Ming Lei wrote: > > IOSQE_SQE_GROUP just starts to queue members after the leader is completed, > > which way is just for simplifying implementation, and this behavior is never > > part of UAPI, and it may be relaxed and members can be queued concurrently > > with leader in future. > > > > However, some resource can't cross OPs, such as kernel buffer, otherwise > > the buffer may be leaked easily in case that any OP failure or application > > panic. > > > > Add flag REQ_F_SQE_GROUP_DEP for allowing members to depend on group leader > > explicitly, so that group members won't be queued until the leader request is > > completed, the kernel resource lifetime can be aligned with group leader > > That's the current and only behaviour, we don't need an extra flag > for that. We can add it back later when anything changes. OK. Thanks, Ming