From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42639) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YNfrm-0007HY-8n for qemu-devel@nongnu.org; Tue, 17 Feb 2015 05:58:59 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YNfri-0001Tz-Qh for qemu-devel@nongnu.org; Tue, 17 Feb 2015 05:58:57 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55617) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YNfri-0001TK-KO for qemu-devel@nongnu.org; Tue, 17 Feb 2015 05:58:54 -0500 Message-ID: <54E31EE1.2090809@redhat.com> Date: Tue, 17 Feb 2015 11:58:41 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <20150122085127.5276.53895.stgit@PASHA-ISP.def.inno> <20150122085215.5276.8878.stgit@PASHA-ISP.def.inno> <54C9FE31.4090404@redhat.com> <001801d03ee3$c8cb7660$5a626320$@Dovgaluk@ispras.ru> <54CF6FA9.7090600@redhat.com> <28583.7738695138$1422880978@news.gmane.org> <54CF793D.6070404@redhat.com> <6071.25815372473$1424089600@news.gmane.org> <54E1E9B1.7090900@redhat.com> <8198.56250095672$1424093273@news.gmane.org> <54E1F14E.3000107@redhat.com> <39577.5216319182$1424093895@news.gmane.org> <54E1F650.5080508@redhat.com> <000001d04a8d$d65fc870$831f5950$@Dovgaluk@ispras.ru> In-Reply-To: <000001d04a8d$d65fc870$831f5950$@Dovgaluk@ispras.ru> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH v8 08/21] cpu: replay instructions sequence List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Pavel Dovgaluk , qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, peter.crosthwaite@xilinx.com, mark.burton@greensocs.com, real@ispras.ru, batuzovk@ispras.ru, maria.klimushenkova@ispras.ru, alex.bennee@linaro.org, afaerber@suse.de, fred.konrad@greensocs.com On 17/02/2015 09:43, Pavel Dovgaluk wrote: >> > int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL); >> > if (deadline == 0) { >> > qemu_clock_notify(QEMU_CLOCK_VIRTUAL); >> > } >> > >> > instead of qemu_notify_event(), and remove these lines from >> > qemu_tcg_cpu_thread_fn. > I tried this one. But there is one problem. > Expiring of the virtual timers is not the only reason of icount expiration in replay mode. > It may be caused by host timers deadline or poll timeout in record mode. In this case > qemu_clock_notify(QEMU_CLOCK_VIRTUAL) will not be called in replay mode and we'll waste time for iothread sleeping. Sure, but unconditional qemu_notify_event() is also wrong. So, to sum up: - it's okay to move code from qemu_tcg_cpu_thread_fn to cpu-exec.c - it's okay to add more qemu_clock_notify calls than just qemu_clock_notify(QEMU_CLOCK_VIRTUAL), each with its own condition - it's better if all these, after being moved to cpu-exec.c, are also extracted in a separate function - it's not okay to do an unconditional qemu_notify_event() in cpu-exec.c, even if it's under "if (replay_mode != NONE)". Thanks for your understanding! :) Paolo