From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NHdgD-0000pm-4n for qemu-devel@nongnu.org; Mon, 07 Dec 2009 08:31:09 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NHdg8-0000gV-8I for qemu-devel@nongnu.org; Mon, 07 Dec 2009 08:31:08 -0500 Received: from [199.232.76.173] (port=50426 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NHdg7-0000gD-MP for qemu-devel@nongnu.org; Mon, 07 Dec 2009 08:31:04 -0500 Received: from mail-yw0-f183.google.com ([209.85.211.183]:47435) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NHdg7-0005VJ-JO for qemu-devel@nongnu.org; Mon, 07 Dec 2009 08:31:03 -0500 Received: by ywh13 with SMTP id 13so4863745ywh.29 for ; Mon, 07 Dec 2009 05:31:02 -0800 (PST) MIME-Version: 1.0 From: Artyom Tarasenko Date: Mon, 7 Dec 2009 14:30:42 +0100 Message-ID: Content-Type: text/plain; charset=ISO-8859-1 Subject: [Qemu-devel] irq latency and tcg List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel , Blue Swirl Can it be that qemu (-system-sparc in my case, but I guess it's more or less similar on all platforms) reacts to irqs slower than a real hardware due to tcg optimizations? I see one test pattern which fails on qemu: nop * N What I observe is that the proper interrupt does take a place, but after the check, so no-one expects it anymore. Is there a way to reduce the interrupt latency? Or maybe there is a good substitute to a nop*N, so that irq would definitely get through in the mean time? Artyom