From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:34181 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726230AbfLIQyn (ORCPT ); Mon, 9 Dec 2019 11:54:43 -0500 Date: Mon, 9 Dec 2019 17:54:30 +0100 From: Cornelia Huck Subject: Re: [kvm-unit-tests PATCH v3 7/9] s390x: css: msch, enable test Message-ID: <20191209175430.5381b328.cohuck@redhat.com> In-Reply-To: <1575649588-6127-8-git-send-email-pmorel@linux.ibm.com> References: <1575649588-6127-1-git-send-email-pmorel@linux.ibm.com> <1575649588-6127-8-git-send-email-pmorel@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Pierre Morel Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, frankja@linux.ibm.com, david@redhat.com, thuth@redhat.com On Fri, 6 Dec 2019 17:26:26 +0100 Pierre Morel wrote: > A second step when testing the channel subsystem is to prepare a channel > for use. > This includes: > - Get the current SubCHannel Information Block (SCHIB) using STSCH > - Update it in memory to set the ENABLE bit > - Tell the CSS that the SCHIB has been modified using MSCH > - Get the SCHIB from the CSS again to verify that the subchannel is > enabled. > > This tests the success of the MSCH instruction by enabling a channel. > > Signed-off-by: Pierre Morel > --- > s390x/css.c | 39 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 39 insertions(+) > > diff --git a/s390x/css.c b/s390x/css.c > index 3d4a986..4c0031c 100644 > --- a/s390x/css.c > +++ b/s390x/css.c > @@ -58,11 +58,50 @@ static void test_enumerate(void) > report("Tested %d devices, %d found", 1, scn, found); > } > > +static void test_enable(void) > +{ > + struct pmcw *pmcw = &schib.pmcw; > + int cc; > + > + if (!test_device_sid) { > + report_skip("No device"); > + return; > + } > + /* Read the SCIB for this subchannel */ s/SCIB/SCHIB/ > + cc = stsch(test_device_sid, &schib); > + if (cc) { > + report("stsch cc=%d", 0, cc); > + return; > + } > + /* Update the SCHIB to enable the channel */ > + pmcw->flags |= PMCW_ENABLE; > + > + /* Tell the CSS we want to modify the subchannel */ > + cc = msch(test_device_sid, &schib); > + if (cc) { > + report("msch cc=%d", 0, cc); So you expect the subchannel to be idle? Probably true, especially as QEMU has no reason to post an unsolicited interrupt for a test device. > + return; > + } > + > + /* Read the SCHIB again to verify the enablement */ > + cc = stsch(test_device_sid, &schib); > + if (cc) { > + report("stsch cc=%d", 0, cc); > + return; > + } > + if (!(pmcw->flags & PMCW_ENABLE)) { > + report("Enable failed. pmcw: %x", 0, pmcw->flags); This check is fine when running under KVM. If this test is modified to run under z/VM in the future, you probably should retry here: I've seen the enable bit 'stick' only after the second msch() there. > + return; > + } > + report("Tested", 1); > +} > + > static struct { > const char *name; > void (*func)(void); > } tests[] = { > { "enumerate (stsch)", test_enumerate }, > + { "enable (msch)", test_enable }, > { NULL, NULL } > }; >