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Violators will be prosecuted for from ; Mon, 2 Dec 2019 18:34:03 -0000 Subject: Re: [kvm-unit-tests PATCH v2 6/9] s390x: css: stsch, enumeration test References: <1574945167-29677-1-git-send-email-pmorel@linux.ibm.com> <1574945167-29677-7-git-send-email-pmorel@linux.ibm.com> <20191202152246.4d627b0e.cohuck@redhat.com> <20191202191541.1ffd987e.cohuck@redhat.com> From: Pierre Morel Date: Mon, 2 Dec 2019 19:33:59 +0100 MIME-Version: 1.0 In-Reply-To: <20191202191541.1ffd987e.cohuck@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Message-Id: Sender: linux-s390-owner@vger.kernel.org List-ID: To: Cornelia Huck Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, frankja@linux.ibm.com, david@redhat.com, thuth@redhat.com On 2019-12-02 19:15, Cornelia Huck wrote: > On Mon, 2 Dec 2019 18:53:16 +0100 > Pierre Morel wrote: > >> On 2019-12-02 15:22, Cornelia Huck wrote: >>> On Thu, 28 Nov 2019 13:46:04 +0100 >>> Pierre Morel wrote: > >>>> +static int test_device_sid; >>>> + >>>> +static void test_enumerate(void) >>>> +{ >>>> + struct pmcw *pmcw = &schib.pmcw; >>>> + int sid; >>>> + int ret, i; >>>> + int found = 0; >>>> + >>>> + for (sid = 0; sid < 0xffff; sid++) { >>>> + ret = stsch(sid|SID_ONE, &schib); >>> >>> This seems a bit odd. You are basically putting the subchannel number >>> into sid, OR in the one, and then use the resulting value as the sid >>> (subchannel identifier). >>> >>>> + if (!ret && (pmcw->flags & PMCW_DNV)) { >>>> + report_info("SID %04x Type %s PIM %x", sid, >>> >>> That's not a sid, but the subchannel number (see above). >>> >>>> + Channel_type[pmcw->st], pmcw->pim); >>>> + for (i = 0; i < 8; i++) { >>>> + if ((pmcw->pim << i) & 0x80) { >>>> + report_info("CHPID[%d]: %02x", i, >>>> + pmcw->chpid[i]); >>>> + break; >>>> + } >>>> + } >>>> + found++; >>>> + >>>> + } >>> >>> Here, you iterate over the 0-0xffff range, even if you got a condition >>> code 3 (indicating no more subchannels in that set). Is that >>> intentional? >> >> I thought there could be more subchannels. >> I need then a break in the loop when this happens. >> I will reread the PoP to see how to find that no more subchannel are in >> that set. > > The fact that cc 3 for stsch == no more subchannels is unfortunately a > bit scattered across the PoP :/ Dug it out some time ago, maybe it's > still in the archives somewhere... So the the subchannel are always one after the other? > >> >>> >>>> + if (found && !test_device_sid) >>>> + test_device_sid = sid|SID_ONE; >>> >>> You set test_device_sid to the last valid subchannel? Why? >> >> The last ? I wanted the first one > > It is indeed the first one, -ENOCOFFEE. Would never happend to me. > >> >> I wanted something easy but I should have explain. >> >> To avoid doing complicated things like doing a sense on each valid >> subchannel I just take the first one. >> Should be enough as we do not go to the device in this test. > > Yes; but you plan to reuse that code, don't you? yes, so I must think about this > >> >>> >>>> + } >>>> + if (!found) { >>>> + report("Found %d devices", 0, found); > > Now that I look at this again: If you got here, you always found 0 > devices, so that message is not super helpful :) yes, found is too much. A cut and past from the time I was happy to find even one! :) > >>>> + return; >>>> + } >>>> + ret = stsch(test_device_sid, &schib); >>> >>> Why do you do a stsch() again? >> >> right, no need. >> In an internal version I used to print some informations from the SCHIB. >> Since in between I overwrote the SHIB, I did it again. >> But in this version; no need. > > You could copy the schib of the subchannel to be tested to a different > place, but I'm not sure it's worth it. > >> >>> >>>> + if (ret) { >>>> + report("Err %d on stsch on sid %08x", 0, ret, test_device_sid); >>>> + return; >>>> + } >>>> + report("Tested", 1); >>>> + return; >>> >>> I don't think you need this return statement. >> >> right I have enough work. :) >> >>> >>> Your test only enumerates devices in the first subchannel set. Do you >>> plan to enhance the test to enable the MSS facility and iterate over >>> all subchannel sets? >> >> Yes, it is something we can do in a following series > > Sure, just asked out of interest :) > Thanks, Regards, Pierre -- Pierre Morel IBM Lab Boeblingen