From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56336) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eeGvZ-00052N-D0 for qemu-devel@nongnu.org; Wed, 24 Jan 2018 04:01:06 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eeGvT-0002Oo-Tg for qemu-devel@nongnu.org; Wed, 24 Jan 2018 04:01:05 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36814) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eeGvT-0002N9-LD for qemu-devel@nongnu.org; Wed, 24 Jan 2018 04:00:59 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7C8475536E for ; Wed, 24 Jan 2018 09:00:58 +0000 (UTC) References: <20180116142316.30486-1-pbonzini@redhat.com> From: Paolo Bonzini Message-ID: Date: Wed, 24 Jan 2018 10:00:51 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 0/4] coroutine-lock: polymorphic CoQueue List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: QEMU Developers On 24/01/2018 04:58, Fam Zheng wrote: > On Tue, Jan 16, 2018 at 10:23 PM, Paolo Bonzini wrote: >> There are cases in which a queued coroutine must be restarted from >> non-coroutine context (with qemu_co_enter_next). In this cases, >> qemu_co_enter_next also needs to be thread-safe, but it cannot use a >> CoMutex and so cannot qemu_co_queue_wait. This happens in curl (which >> right now is rolling its own list of Coroutines) and will happen in >> Fam's NVMe driver as well. >> >> This series extracts the idea of a polymorphic lockable object >> from my "scoped lock guard" proposal, and applies it to CoQueue. >> The implementation of QemuLockable is similar to C11 _Generic, but >> redone using the preprocessor and GCC builtins for compatibility. >> >> In general, while a bit on the esoteric side, the functionality used >> to emulate _Generic is fairly old in GCC, and the builtins are already >> used by include/qemu/atomic.h; the series was tested with Fedora 27 (boot >> Damn Small Linux via http) and CentOS 6 (compiled only). >> >> Paolo >> >> v1->v2: fix typos and copyright year > > Reviewed-by: Fam Zheng > > Should I include this series in my pull request for the NVMe driver? Yes, please. This is within block layer area, since CoQueue and block/curl.c are still the only users. Paolo