From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-2.mimecast.com ([207.211.31.81]:44279 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726782AbgGILlJ (ORCPT ); Thu, 9 Jul 2020 07:41:09 -0400 Date: Thu, 9 Jul 2020 13:40:56 +0200 From: Cornelia Huck Subject: Re: [kvm-unit-tests PATCH v11 8/9] s390x: css: msch, enable test Message-ID: <20200709134056.0d267b6c.cohuck@redhat.com> In-Reply-To: <1594282068-11054-9-git-send-email-pmorel@linux.ibm.com> References: <1594282068-11054-1-git-send-email-pmorel@linux.ibm.com> <1594282068-11054-9-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, drjones@redhat.com On Thu, 9 Jul 2020 10:07:47 +0200 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 and the specified ISC > - 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 and uses the specified ISC. > - If the command succeeds but subchannel is not enabled or the ISC > field is not as expected, retry a predefined retries count. > - If the command fails, report the failure and do not retry, even > if cc indicates a busy/status pending as we do not expect this. > > This tests the MSCH instruction to enable a channel successfully. > Retries are done and in case of error, and if the retries count > is exceeded, a report is made. > > Signed-off-by: Pierre Morel > Acked-by: Thomas Huth > Reviewed-by: Cornelia Huck > --- > lib/s390x/css.h | 8 +++-- > lib/s390x/css_lib.c | 72 +++++++++++++++++++++++++++++++++++++++++++++ > s390x/css.c | 15 ++++++++++ > 3 files changed, 92 insertions(+), 3 deletions(-) (...) > +/* > + * css_msch: enable subchannel and set with specified ISC "css_enable: enable the subchannel with the specified ISC" ? > + * @schid: Subchannel Identifier > + * @isc : number of the interruption subclass to use > + * Return value: > + * On success: 0 > + * On error the CC of the faulty instruction > + * or -1 if the retry count is exceeded. > + */ > +int css_enable(int schid, int isc) > +{ > + struct pmcw *pmcw = &schib.pmcw; > + int retry_count = 0; > + uint16_t flags; > + int cc; > + > + /* Read the SCHIB for this subchannel */ > + cc = stsch(schid, &schib); > + if (cc) { > + report_info("stsch: sch %08x failed with cc=%d", schid, cc); > + return cc; > + } > + > + flags = PMCW_ENABLE | (isc << PMCW_ISC_SHIFT); > + if ((pmcw->flags & flags) == flags) { I think you want (pmcw->flags & PMCW_ENABLE) == PMCW_ENABLE -- this catches the case of "subchannel has been enabled before, but with a different isc". > + report_info("stsch: sch %08x already enabled", schid); > + return 0; > + } (...)