From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:45390) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Rkhri-0003Gz-5f for qemu-devel@nongnu.org; Tue, 10 Jan 2012 15:00:18 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Rkhrd-0006PY-Sx for qemu-devel@nongnu.org; Tue, 10 Jan 2012 15:00:14 -0500 Received: from lo.gmane.org ([80.91.229.12]:54707) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Rkhrd-0006PQ-Nm for qemu-devel@nongnu.org; Tue, 10 Jan 2012 15:00:09 -0500 Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1Rkhrc-0001gv-Nm for qemu-devel@nongnu.org; Tue, 10 Jan 2012 21:00:08 +0100 Received: from 93-34-200-238.ip51.fastwebnet.it ([93.34.200.238]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 10 Jan 2012 21:00:08 +0100 Received: from pbonzini by 93-34-200-238.ip51.fastwebnet.it with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 10 Jan 2012 21:00:08 +0100 From: Paolo Bonzini Date: Tue, 10 Jan 2012 20:59:00 +0100 Message-ID: References: <1326222656-26588-1-git-send-email-aliguori@us.ibm.com> <1326222656-26588-15-git-send-email-aliguori@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit In-Reply-To: <1326222656-26588-15-git-send-email-aliguori@us.ibm.com> Subject: Re: [Qemu-devel] [PATCH 15/15] qtest: add rtc-test test-case List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org On 01/10/2012 08:10 PM, Anthony Liguori wrote: > + sec = cmos_read(0x00); > + min = cmos_read(0x02); > + hour = cmos_read(0x04); > + mday = cmos_read(0x07); > + mon = cmos_read(0x08); > + year = cmos_read(0x09); Please use identifiers for register numbers. > + /* > + * This check assumes a few things. First, we cannot guarantee that we get > + * a consistent reading from the wall clock because we may hit an edge of > + * the clock while reading. To work around this, we read four clock readings > + * such that at least two of them should match. We need to assume that one > + * reading is corrupt so we need four readings to ensure that we have at > + * least two consecutive identical readings > + * > + * It's also possible that we'll cross an edge reading the host clock so > + * simply check to make sure that the clock reading is within the period of > + * when we expect it to be. > + */ This seems broken to me. The right thing to do would be to run the test with vm_clock for the rtc_clock, add a way for the qtest machine to bump the vm_clock to the next event, and busy loop running that method using UIP like you would do on hardware. Paolo