On 2019-12-12 11:18, Cornelia Huck wrote:
On Wed, 11 Dec 2019 16:46:07 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
First step for testing the channel subsystem is to enumerate the css and
retrieve the css devices.
This tests the success of STSCH I/O instruction, we do not test the
reaction of the VM for an instruction with wrong parameters.
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
lib/s390x/css.h | 1 +
s390x/Makefile | 2 ++
s390x/css.c | 88 +++++++++++++++++++++++++++++++++++++++++++++
s390x/unittests.cfg | 4 +++
4 files changed, 95 insertions(+)
create mode 100644 s390x/css.c
diff --git a/s390x/css.c b/s390x/css.c
new file mode 100644
index 0000000..dfab35f
--- /dev/null
+++ b/s390x/css.c
@@ -0,0 +1,88 @@
+/*
+ * Channel Subsystem tests
+ *
+ * Copyright (c) 2019 IBM Corp
+ *
+ * Authors:
+ * Pierre Morel <pmorel@xxxxxxxxxxxxx>
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#include <libcflat.h>
+#include <alloc_phys.h>
+#include <asm/page.h>
+#include <string.h>
+#include <interrupt.h>
+#include <asm/arch_def.h>
+#include <asm/time.h>
+
+#include <css.h>
+
+#define SID_ONE 0x00010000
+
+static struct schib schib;
+static int test_device_sid;
+
+static void test_enumerate(void)
+{
+ struct pmcw *pmcw = &schib.pmcw;
+ int cc;
+ int scn;
+ int scn_found = 0;
+
+ for (scn = 0; scn < 0xffff; scn++) {
+ cc = stsch(scn|SID_ONE, &schib);
+ switch (cc) {
+ case 0: /* 0 means SCHIB stored */
+ break;
+ case 3: /* 3 means no more channels */
+ goto out;
+ default: /* 1 or 2 should never happened for STSCH */
+ report(0, "Unexpected cc=%d on scn 0x%x", cc, scn);
Spell out "subchannel number"?
Yes I can do this.
+ return;
+ }
+ if (cc)
+ break;
Isn't that redundant?
fully.
+ /* We silently only support type 0, a.k.a. I/O channels */
s/silently/currently/ ?
OK
+ if (PMCW_CHANNEL_TYPE(pmcw) != 0)
+ continue;
+ /* We ignore I/O channels without valid devices */
+ if (!(pmcw->flags & PMCW_DNV))
+ continue;
+ /* We keep track of the first device as our test device */
+ if (!test_device_sid)
+ test_device_sid = scn|SID_ONE;
+ scn_found++;
+ }
+out:
+ if (!scn_found) {
+ report(0, "Devices, Tested: %d, no I/O type found", scn);
It's no I/O _devices_ found, isn't it? There might have been I/O
subchannels, but none with a valid device...
yes, I will update the stats.
+ return;
+ }
+ report(1, "Devices, tested: %d, I/O type: %d", scn, scn_found);
As you're testing this anyway: what about tracking _all_ numbers here?
I.e., advance a counter for I/O subchannels as well, even if !dnv, and
have an output like >
"Tested subchannels: 20, I/O subchannels: 18, I/O devices: 10"
or so?
Yes, will do.
+}
+
+static struct {
+ const char *name;
+ void (*func)(void);
+} tests[] = {
+ { "enumerate (stsch)", test_enumerate },
+ { NULL, NULL }
+};
+
+int main(int argc, char *argv[])
+{
+ int i;
+
+ report_prefix_push("Channel Sub-System");
s/Channel Sub-System/Channel Subsystem/ ?
OK, (it was because of "CSS").
+ for (i = 0; tests[i].name; i++) {
+ report_prefix_push(tests[i].name);
+ tests[i].func();
+ report_prefix_pop();
+ }
+ report_prefix_pop();
+
+ return report_summary();
+}
This basically looks sane to me now.
Just some additional considerations (we can do that on top, no need to
do surgery here right now):
I currently have the (not sure how sensible) idea to add some optional
testing for vfio-ccw, and this would obviously need some I/O routines as
well. So, in the long run, it would be good if something like this
stsch-loop could be factored out to a kind of library function. Just
some thoughts for now :)
Yes, could be useful.
Thanks,
Regards,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
