[kvm-unit-tests PATCH v2 2/5] s390x: css: simplifications of the tests

Pierre Morel
2021-02-10T13:21:49Z

In order to ease the writing of tests based on:
- interrupt
- enabling a subchannel
- using multiple I/O on a channel without disabling it

We do the following simplifications:
- the I/O interrupt handler is registered on CSS initialization
- We do not enable again a subchannel in senseid if it is already
enabled
- we add a css_enabled() function to test if a subchannel is enabled

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
lib/s390x/css.h | 1 +
lib/s390x/css_lib.c | 37 ++++++++++++++++++++++----------
s390x/css.c | 51 ++++++++++++++++++++++++++-------------------
3 files changed, 56 insertions(+), 33 deletions(-)

diff --git a/lib/s390x/css.h b/lib/s390x/css.h
index 1e317d1..fa8775f 100644
--- a/lib/s390x/css.h
+++ b/lib/s390x/css.h
@@ -278,6 +278,7 @@ int css_enumerate(void);

#define IO_SCH_ISC 3
int css_enable(int schid, int isc);
+bool css_enabled(int schid);

/* Library functions */
int start_ccw1_chain(unsigned int sid, struct ccw1 *ccw);
diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
index 88aa7a1..5426a6b 100644
--- a/lib/s390x/css_lib.c
+++ b/lib/s390x/css_lib.c
@@ -180,6 +180,31 @@ out:
return schid;
}

+/*
+ * css_enabled: report if the subchannel is enabled
+ * @schid: Subchannel Identifier
+ * Return value:
+ * true if the subchannel is enabled
+ * false otherwise
+ */
+bool css_enabled(int schid)
+{
+ struct pmcw *pmcw = &schib.pmcw;
+ int cc;
+
+ cc = stsch(schid, &schib);
+ if (cc) {
+ report_info("stsch: updating sch %08x failed with cc=%d",
+ schid, cc);
+ return false;
+ }
+
+ if (!(pmcw->flags & PMCW_ENABLE)) {
+ report_info("stsch: sch %08x not enabled", schid);
+ return false;
+ }
+ return true;
+}
/*
* css_enable: enable the subchannel with the specified ISC
* @schid: Subchannel Identifier
@@ -229,18 +254,8 @@ retry:
/*
* Read the SCHIB again to verify the enablement
*/
- cc = stsch(schid, &schib);
- if (cc) {
- report_info("stsch: updating sch %08x failed with cc=%d",
- schid, cc);
- return cc;
- }
-
- if ((pmcw->flags & flags) == flags) {
- report_info("stsch: sch %08x successfully modified after %d retries",
- schid, retry_count);
+ if (css_enabled(schid))
return 0;
- }

if (retry_count++ < MAX_ENABLE_RETRIES) {
mdelay(10); /* the hardware was not ready, give it some time */
diff --git a/s390x/css.c b/s390x/css.c
index 18dbf01..d4b3cc8 100644
--- a/s390x/css.c
+++ b/s390x/css.c
@@ -56,36 +56,27 @@ static void test_enable(void)
* - We need the test device as the first recognized
* device by the enumeration.
*/
-static void test_sense(void)
+static bool do_test_sense(void)
{
struct ccw1 *ccw;
+ bool success = false;
int ret;
int len;

if (!test_device_sid) {
report_skip("No device");
- return;
+ return success;
}

- ret = css_enable(test_device_sid, IO_SCH_ISC);
- if (ret) {
- report(0, "Could not enable the subchannel: %08x",
- test_device_sid);
- return;
- }
-
- ret = register_io_int_func(css_irq_io);
- if (ret) {
- report(0, "Could not register IRQ handler");
- return;
+ if (!css_enabled(test_device_sid)) {
+ report(0, "enabling subchannel %08x", test_device_sid);
+ return success;
}

- lowcore_ptr->io_int_param = 0;
-
senseid = alloc_io_mem(sizeof(*senseid), 0);
if (!senseid) {
report(0, "Allocation of senseid");
- goto error_senseid;
+ return success;
}

ccw = ccw_alloc(CCW_CMD_SENSE_ID, senseid, sizeof(*senseid), CCW_F_SLI);
@@ -129,16 +120,21 @@ static void test_sense(void)
report_info("reserved 0x%02x cu_type 0x%04x cu_model 0x%02x dev_type 0x%04x dev_model 0x%02x",
senseid->reserved, senseid->cu_type, senseid->cu_model,
senseid->dev_type, senseid->dev_model);
+ report_info("cu_type expected 0x%04x got 0x%04x", (uint16_t)cu_type,
+ senseid->cu_type);

- report(senseid->cu_type == cu_type, "cu_type expected 0x%04x got 0x%04x",
- (uint16_t)cu_type, senseid->cu_type);
+ success = senseid->cu_type == cu_type;

error:
free_io_mem(ccw, sizeof(*ccw));
error_ccw:
free_io_mem(senseid, sizeof(*senseid));
-error_senseid:
- unregister_io_int_func(css_irq_io);
+ return success;
+}
+
+static void test_sense(void)
+{
+ report(do_test_sense(), "Got CU type expected");
}

static void css_init(void)
@@ -146,8 +142,19 @@ static void css_init(void)
int ret;

ret = get_chsc_scsc();
- if (!ret)
- report(1, " ");
+ if (ret) {
+ report(0, "Could not get CHSC Characteristics");
+ return;
+ }
+
+ ret = register_io_int_func(css_irq_io);
+ if (ret) {
+ report(0, "Could not register IRQ handler");
+ return;
+ }
+ lowcore_ptr->io_int_param = 0;
+
+ report(1, "CSS initialized");
}

static struct {
--
2.17.1