From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38260) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZP50i-0004uw-JL for qemu-devel@nongnu.org; Tue, 11 Aug 2015 04:34:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZP50d-0005Vq-EG for qemu-devel@nongnu.org; Tue, 11 Aug 2015 04:34:16 -0400 Received: from mail-wi0-x230.google.com ([2a00:1450:400c:c05::230]:35562) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZP50d-0005Vl-2d for qemu-devel@nongnu.org; Tue, 11 Aug 2015 04:34:11 -0400 Received: by wicne3 with SMTP id ne3so51111642wic.0 for ; Tue, 11 Aug 2015 01:34:10 -0700 (PDT) Sender: Paolo Bonzini References: <1439220437-23957-1-git-send-email-fred.konrad@greensocs.com> <1439220437-23957-8-git-send-email-fred.konrad@greensocs.com> <55C8D31A.8070703@redhat.com> <55C99A57.2090406@greensocs.com> From: Paolo Bonzini Message-ID: <55C9B37E.2020700@redhat.com> Date: Tue, 11 Aug 2015 10:34:06 +0200 MIME-Version: 1.0 In-Reply-To: <55C99A57.2090406@greensocs.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH V7 07/19] protect TBContext with tb_lock. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Frederic Konrad , qemu-devel@nongnu.org, mttcg@listserver.greensocs.com Cc: alex.bennee@linaro.org, mark.burton@greensocs.com, a.rigo@virtualopensystems.com, guillaume.delbergue@greensocs.com On 11/08/2015 08:46, Frederic Konrad wrote: >> I think you should start easy and reuse the existing tb_lock code in >> cpu-exec.c: > > I think it's definitely not sufficient. Is user-mode multithread still > working today? For some definition of "working", yes. It's not sufficient, but it's a good start. The main problem with user-mode multithreading is that there is no clear lock hierarchy between mmap_lock and tb_lock. But this is not a problem for softmmu. Paolo