From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46162) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YDC5l-000337-QN for qemu-devel@nongnu.org; Mon, 19 Jan 2015 08:10:06 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YDC5i-00016W-HN for qemu-devel@nongnu.org; Mon, 19 Jan 2015 08:10:05 -0500 Received: from mail.ispras.ru ([83.149.199.45]:60578) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YDC5i-00013T-8w for qemu-devel@nongnu.org; Mon, 19 Jan 2015 08:10:02 -0500 From: "Pavel Dovgaluk" References: <20150112115944.3504.66763.stgit@PASHA-ISP> <20150112120054.3504.35220.stgit@PASHA-ISP> <54B3BA89.6080705@redhat.com> <000501d02f12$61177b30$23467190$@Dovgaluk@ispras.ru> <54B4E79C.5010201@redhat.com> <000101d03162$f2d2ed50$d878c7f0$@Dovgaluk@ispras.ru> <54BCEFD1.5040702@redhat.com> <000c01d033df$ece29420$c6a7bc60$@Dovgaluk@ispras.ru> <54BCF55D.7040607@redhat.com> <000d01d033e5$90d30420$b2790c60$@Dovgaluk@ispras.ru> <54BCFF4E.408@redhat.com> <000e01d033e8$18a28e00$49e7aa00$@Dovgaluk@ispras.ru> <54BD006A.2080200@redhat.com> In-Reply-To: <54BD006A.2080200@redhat.com> Date: Mon, 19 Jan 2015 16:10:01 +0300 Message-ID: <000f01d033e9$3baf86e0$b30e94a0$@Dovgaluk@ispras.ru> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Language: ru Subject: Re: [Qemu-devel] [RFC PATCH v7 12/21] replay: recording and replaying clock ticks List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: 'Paolo Bonzini' , qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, peter.crosthwaite@xilinx.com, alex.bennee@linaro.org, mark.burton@greensocs.com, real@ispras.ru, batuzovk@ispras.ru, maria.klimushenkova@ispras.ru, afaerber@suse.de, fred.konrad@greensocs.com > From: Paolo Bonzini [mailto:pbonzini@redhat.com] > On 19/01/2015 14:01, Pavel Dovgaluk wrote: > > > It would be easier if you pointed me to actual code in the series. But > > > this doesn't seem impossible to fix by atomically writing the 'E' and > > > 'A' in the same critical section. > > > > Because 'A' is written only inside some of the replay_run_event callbacks. > > It depends on type of the event and it's processing function inside the QEMU core. > > There could be no 'A' at all. > > Why can't that code write the 'E' as well? Because such callbacks do not know that they are called from record/replay event. They may be called from record/replay code and from other parts of QEMU. And they may write save something low-level like timer request. Pavel Dovgalyuk