From: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
To: Thomas Huth <thuth@redhat.com>,
Janosch Frank <frankja@linux.ibm.com>,
Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Janis Schoetterl-Glausch <scgl@linux.ibm.com>,
David Hildenbrand <david@redhat.com>,
kvm@vger.kernel.org, linux-s390@vger.kernel.org
Subject: [kvm-unit-tests PATCH v4 0/2] Add specification exception tests
Date: Tue, 11 Jan 2022 17:38:59 +0100 [thread overview]
Message-ID: <20220111163901.1263736-1-scgl@linux.ibm.com> (raw)
Test that specification exceptions cause the correct interruption code
during both normal and transactional execution.
v3 -> v4
remove iterations argument in order to simplify the code
for manual performance testing adding a for loop is easy
move report out of fixup_invalid_psw
simplify/improve readability of triggers
use positive error values
v2 -> v3
remove non-ascii symbol
clean up load_psw
fix nits
v1 -> v2
Add license and test description
Split test patch into normal test and transactional execution test
Add comments to
invalid PSW fixup function
with_transaction
Rename some variables/functions
Pass mask as single parameter to asm
Get rid of report_info_if macro
Introduce report_pass/fail and use them
Janis Schoetterl-Glausch (2):
s390x: Add specification exception test
s390x: Test specification exceptions during transaction
s390x/Makefile | 1 +
lib/s390x/asm/arch_def.h | 1 +
s390x/spec_ex.c | 323 +++++++++++++++++++++++++++++++++++++++
s390x/unittests.cfg | 3 +
4 files changed, 328 insertions(+)
create mode 100644 s390x/spec_ex.c
Range-diff against v3:
1: 75d0bf1 ! 1: a242e84 s390x: Add specification exception test
@@ Commit message
s390x: Add specification exception test
Generate specification exceptions and check that they occur.
- With the iterations argument one can check if specification
- exception interpretation occurs, e.g. by using a high value and
- checking that the debugfs counters are substantially lower.
- The argument is also useful for estimating the performance benefit
- of interpretation.
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
## s390x/Makefile ##
-@@ s390x/Makefile: tests += $(TEST_DIR)/mvpg.elf
- tests += $(TEST_DIR)/uv-host.elf
+@@ s390x/Makefile: tests += $(TEST_DIR)/uv-host.elf
tests += $(TEST_DIR)/edat.elf
tests += $(TEST_DIR)/mvpg-sie.elf
+ tests += $(TEST_DIR)/spec_ex-sie.elf
+tests += $(TEST_DIR)/spec_ex.elf
+ tests += $(TEST_DIR)/firq.elf
tests_binary = $(patsubst %.elf,%.bin,$(tests))
- ifneq ($(HOST_KEY_DOCUMENT),)
## s390x/spec_ex.c (new) ##
@@
@@ s390x/spec_ex.c (new)
+ *
+ * Specification exception test.
+ * Tests that specification exceptions occur when expected.
++ *
++ * Can be extended by adding triggers to spec_ex_triggers, see comments below.
+ */
+#include <stdlib.h>
+#include <libcflat.h>
+#include <asm/interrupt.h>
-+#include <asm/facility.h>
+
+static struct lowcore *lc = (struct lowcore *) 0;
+
-+static bool expect_invalid_psw;
++static bool invalid_psw_expected;
+static struct psw expected_psw;
++static struct psw invalid_psw;
+static struct psw fixup_psw;
+
+/* The standard program exception handler cannot deal with invalid old PSWs,
@@ s390x/spec_ex.c (new)
+ */
+static void fixup_invalid_psw(void)
+{
-+ if (expect_invalid_psw) {
-+ report(expected_psw.mask == lc->pgm_old_psw.mask
-+ && expected_psw.addr == lc->pgm_old_psw.addr,
-+ "Invalid program new PSW as expected");
-+ expect_invalid_psw = false;
-+ }
++ // signal occurrence of invalid psw fixup
++ invalid_psw_expected = false;
++ invalid_psw = lc->pgm_old_psw;
+ lc->pgm_old_psw = fixup_psw;
+}
+
+/* Load possibly invalid psw, but setup fixup_psw before,
+ * so that *fixup_invalid_psw() can bring us back onto the right track.
++ * Also acts as compiler barrier, -> none required in expect/check_invalid_psw
+ */
+static void load_psw(struct psw psw)
+{
+ uint64_t scratch;
+
+ fixup_psw.mask = extract_psw_mask();
-+ asm volatile (
-+ " larl %[scratch],nop%=\n"
++ asm volatile ( "larl %[scratch],nop%=\n"
+ " stg %[scratch],%[addr]\n"
+ " lpswe %[psw]\n"
+ "nop%=: nop\n"
@@ s390x/spec_ex.c (new)
+ );
+}
+
-+static void psw_bit_12_is_1(void)
++static void expect_invalid_psw(struct psw psw)
+{
-+ expected_psw.mask = 0x0008000000000000;
-+ expected_psw.addr = 0x00000000deadbeee;
-+ expect_invalid_psw = true;
++ expected_psw = psw;
++ invalid_psw_expected = true;
++}
++
++static int check_invalid_psw(void)
++{
++ // toggled to signal occurrence of invalid psw fixup
++ if (!invalid_psw_expected) {
++ if (expected_psw.mask == invalid_psw.mask &&
++ expected_psw.addr == invalid_psw.addr)
++ return 0;
++ report_fail("Wrong invalid PSW");
++ } else {
++ report_fail("Expected exception due to invalid PSW");
++ }
++ return 1;
++}
++
++static int psw_bit_12_is_1(void)
++{
++ struct psw invalid = { .mask = 0x0008000000000000, .addr = 0x00000000deadbeee};
++
++ expect_invalid_psw(invalid);
+ load_psw(expected_psw);
++ return check_invalid_psw();
+}
+
-+static void bad_alignment(void)
++static int bad_alignment(void)
+{
-+ uint32_t words[5] = {0, 0, 0};
-+ uint32_t (*bad_aligned)[4];
-+
-+ register uint64_t r1 asm("6");
-+ register uint64_t r2 asm("7");
-+ if (((uintptr_t)&words[0]) & 0xf)
-+ bad_aligned = (uint32_t (*)[4])&words[0];
-+ else
-+ bad_aligned = (uint32_t (*)[4])&words[1];
-+ asm volatile ("lpq %0,%2"
-+ : "=r"(r1), "=r"(r2)
-+ : "T"(*bad_aligned)
++ uint32_t words[5] __attribute__((aligned(16)));
++ uint32_t (*bad_aligned)[4] = (uint32_t (*)[4])&words[1];
++
++ asm volatile ("lpq %%r6,%[bad]"
++ : : [bad] "T"(*bad_aligned)
++ : "%r6", "%r7"
+ );
++ return 0;
+}
+
-+static void not_even(void)
++static int not_even(void)
+{
-+ uint64_t quad[2];
++ uint64_t quad[2] __attribute__((aligned(16))) = {0};
+
-+ register uint64_t r1 asm("7");
-+ register uint64_t r2 asm("8");
-+ asm volatile (".insn rxy,0xe3000000008f,%0,%2" //lpq %0,%2
-+ : "=r"(r1), "=r"(r2)
-+ : "T"(quad)
++ asm volatile (".insn rxy,0xe3000000008f,%%r7,%[quad]" //lpq %%r7,%[quad]
++ : : [quad] "T"(quad)
++ : "%r7", "%r8"
+ );
++ return 0;
+}
+
++/*
++ * Harness for specification exception testing.
++ * func only triggers exception, reporting is taken care of automatically.
++ */
+struct spec_ex_trigger {
+ const char *name;
-+ void (*func)(void);
++ int (*func)(void);
+ void (*fixup)(void);
+};
+
++/* List of all tests to execute */
+static const struct spec_ex_trigger spec_ex_triggers[] = {
-+ { "psw_bit_12_is_1", &psw_bit_12_is_1, &fixup_invalid_psw},
-+ { "bad_alignment", &bad_alignment, NULL},
-+ { "not_even", ¬_even, NULL},
-+ { NULL, NULL, NULL},
++ { "psw_bit_12_is_1", &psw_bit_12_is_1, &fixup_invalid_psw },
++ { "bad_alignment", &bad_alignment, NULL },
++ { "not_even", ¬_even, NULL },
++ { NULL, NULL, NULL },
+};
+
-+struct args {
-+ uint64_t iterations;
-+};
-+
-+static void test_spec_ex(struct args *args,
-+ const struct spec_ex_trigger *trigger)
++static void test_spec_ex(const struct spec_ex_trigger *trigger)
+{
+ uint16_t expected_pgm = PGM_INT_CODE_SPECIFICATION;
+ uint16_t pgm;
-+ unsigned int i;
-+
-+ for (i = 0; i < args->iterations; i++) {
-+ expect_pgm_int();
-+ register_pgm_cleanup_func(trigger->fixup);
-+ trigger->func();
-+ register_pgm_cleanup_func(NULL);
-+ pgm = clear_pgm_int();
-+ if (pgm != expected_pgm) {
-+ report_fail("Program interrupt: expected(%d) == received(%d)",
-+ expected_pgm,
-+ pgm);
-+ return;
-+ }
-+ }
-+ report_pass("Program interrupt: always expected(%d) == received(%d)",
-+ expected_pgm,
-+ expected_pgm);
-+}
-+
-+static struct args parse_args(int argc, char **argv)
-+{
-+ struct args args = {
-+ .iterations = 1,
-+ };
-+ unsigned int i;
-+ long arg;
-+ bool no_arg;
-+ char *end;
-+
-+ for (i = 1; i < argc; i++) {
-+ no_arg = true;
-+ if (i < argc - 1) {
-+ no_arg = *argv[i + 1] == '\0';
-+ arg = strtol(argv[i + 1], &end, 10);
-+ no_arg |= *end != '\0';
-+ no_arg |= arg < 0;
-+ }
-+
-+ if (!strcmp("--iterations", argv[i])) {
-+ if (no_arg)
-+ report_abort("--iterations needs a positive parameter");
-+ args.iterations = arg;
-+ ++i;
-+ } else {
-+ report_abort("Unsupported parameter '%s'",
-+ argv[i]);
-+ }
-+ }
-+ return args;
++ int rc;
++
++ expect_pgm_int();
++ register_pgm_cleanup_func(trigger->fixup);
++ rc = trigger->func();
++ register_pgm_cleanup_func(NULL);
++ if (rc)
++ return;
++ pgm = clear_pgm_int();
++ report(pgm == expected_pgm, "Program interrupt: expected(%d) == received(%d)",
++ expected_pgm, pgm);
+}
+
+int main(int argc, char **argv)
+{
+ unsigned int i;
+
-+ struct args args = parse_args(argc, argv);
-+
+ report_prefix_push("specification exception");
+ for (i = 0; spec_ex_triggers[i].name; i++) {
+ report_prefix_push(spec_ex_triggers[i].name);
-+ test_spec_ex(&args, &spec_ex_triggers[i]);
++ test_spec_ex(&spec_ex_triggers[i]);
+ report_prefix_pop();
+ }
+ report_prefix_pop();
@@ s390x/spec_ex.c (new)
+}
## s390x/unittests.cfg ##
-@@ s390x/unittests.cfg: file = edat.elf
+@@ s390x/unittests.cfg: file = mvpg-sie.elf
+ [spec_ex-sie]
+ file = spec_ex-sie.elf
- [mvpg-sie]
- file = mvpg-sie.elf
-+
+[spec_ex]
+file = spec_ex.elf
++
+ [firq-linear-cpu-ids]
+ file = firq.elf
+ timeout = 20
2: 0593951 ! 2: 16ce8bb s390x: Test specification exceptions during transaction
@@ s390x/spec_ex.c
+ * This includes specification exceptions occurring during transactional execution
+ * as these result in another interruption code (the transactional-execution-aborted
+ * bit is set).
+ *
+ * Can be extended by adding triggers to spec_ex_triggers, see comments below.
*/
#include <stdlib.h>
+#include <htmintrin.h>
#include <libcflat.h>
+#include <asm/barrier.h>
#include <asm/interrupt.h>
- #include <asm/facility.h>
++#include <asm/facility.h>
+
+ static struct lowcore *lc = (struct lowcore *) 0;
-@@ s390x/spec_ex.c: static void not_even(void)
+@@ s390x/spec_ex.c: static int not_even(void)
+ /*
+ * Harness for specification exception testing.
+ * func only triggers exception, reporting is taken care of automatically.
++ * If a trigger is transactable it will also be executed during a transaction.
+ */
struct spec_ex_trigger {
const char *name;
- void (*func)(void);
+ int (*func)(void);
+ bool transactable;
void (*fixup)(void);
};
+ /* List of all tests to execute */
static const struct spec_ex_trigger spec_ex_triggers[] = {
-- { "psw_bit_12_is_1", &psw_bit_12_is_1, &fixup_invalid_psw},
-- { "bad_alignment", &bad_alignment, NULL},
-- { "not_even", ¬_even, NULL},
-- { NULL, NULL, NULL},
-+ { "psw_bit_12_is_1", &psw_bit_12_is_1, false, &fixup_invalid_psw},
-+ { "bad_alignment", &bad_alignment, true, NULL},
-+ { "not_even", ¬_even, true, NULL},
-+ { NULL, NULL, true, NULL},
- };
-
- struct args {
- uint64_t iterations;
-+ uint64_t max_retries;
-+ uint64_t suppress_info;
-+ uint64_t max_failures;
-+ bool diagnose;
+- { "psw_bit_12_is_1", &psw_bit_12_is_1, &fixup_invalid_psw },
+- { "bad_alignment", &bad_alignment, NULL },
+- { "not_even", ¬_even, NULL },
+- { NULL, NULL, NULL },
++ { "psw_bit_12_is_1", &psw_bit_12_is_1, false, &fixup_invalid_psw },
++ { "bad_alignment", &bad_alignment, true, NULL },
++ { "not_even", ¬_even, true, NULL },
++ { NULL, NULL, false, NULL },
};
- static void test_spec_ex(struct args *args,
-@@ s390x/spec_ex.c: static void test_spec_ex(struct args *args,
- expected_pgm);
+ static void test_spec_ex(const struct spec_ex_trigger *trigger)
+@@ s390x/spec_ex.c: static void test_spec_ex(const struct spec_ex_trigger *trigger)
+ expected_pgm, pgm);
}
+#define TRANSACTION_COMPLETED 4
@@ s390x/spec_ex.c: static void test_spec_ex(struct args *args,
+ * being NULL to keep things simple
+ */
+static int __attribute__((nonnull))
-+with_transaction(void (*trigger)(void), struct __htm_tdb *diagnose)
++with_transaction(int (*trigger)(void), struct __htm_tdb *diagnose)
+{
+ int cc;
+
+ cc = __builtin_tbegin(diagnose);
+ if (cc == _HTM_TBEGIN_STARTED) {
++ /* return code is meaningless: transaction needs to complete
++ * in order to return and completion indicates a test failure
++ */
+ trigger();
+ __builtin_tend();
-+ return -TRANSACTION_COMPLETED;
++ return TRANSACTION_COMPLETED;
+ } else {
-+ return -cc;
++ return cc;
+ }
+}
+
@@ s390x/spec_ex.c: static void test_spec_ex(struct args *args,
+ for (i = 0; i < max_retries; i++) {
+ expect_pgm_int();
+ trans_result = with_transaction(trigger->func, tdb);
-+ if (trans_result == -_HTM_TBEGIN_TRANSIENT) {
++ if (trans_result == _HTM_TBEGIN_TRANSIENT) {
+ mb();
+ pgm = lc->pgm_int_code;
+ if (pgm == 0)
@@ s390x/spec_ex.c: static void test_spec_ex(struct args *args,
+ }
+ return trans_result;
+ }
-+ return -TRANSACTION_MAX_RETRIES;
++ return TRANSACTION_MAX_RETRIES;
+}
+
++struct args {
++ uint64_t max_retries;
++ bool diagnose;
++};
++
+static void test_spec_ex_trans(struct args *args, const struct spec_ex_trigger *trigger)
+{
+ const uint16_t expected_pgm = PGM_INT_CODE_SPECIFICATION
-+ | PGM_INT_CODE_TX_ABORTED_EVENT;
++ | PGM_INT_CODE_TX_ABORTED_EVENT;
+ union {
+ struct __htm_tdb tdb;
+ uint64_t dwords[sizeof(struct __htm_tdb) / sizeof(uint64_t)];
+ } diag;
-+ unsigned int i, failures = 0;
++ unsigned int i;
+ int trans_result;
+
+ if (!test_facility(73)) {
@@ s390x/spec_ex.c: static void test_spec_ex(struct args *args,
+ }
+ ctl_set_bit(0, CTL0_TRANSACT_EX_CTL); /* enable transactional-exec */
+
-+ for (i = 0; i < args->iterations && failures <= args->max_failures; i++) {
-+ register_pgm_cleanup_func(trigger->fixup);
-+ trans_result = retry_transaction(trigger, args->max_retries, &diag.tdb, expected_pgm);
-+ register_pgm_cleanup_func(NULL);
-+ switch (trans_result) {
-+ case 0:
-+ continue;
-+ case -_HTM_TBEGIN_INDETERMINATE:
-+ case -_HTM_TBEGIN_PERSISTENT:
-+ if (failures < args->suppress_info)
-+ report_info("transaction failed with cc %d",
-+ -trans_result);
-+ break;
-+ case -_HTM_TBEGIN_TRANSIENT:
-+ report_fail("Program interrupt: expected(%d) == received(%d)",
-+ expected_pgm,
-+ clear_pgm_int());
-+ goto out;
-+ case -TRANSACTION_COMPLETED:
-+ report_fail("Transaction completed without exception");
-+ goto out;
-+ case -TRANSACTION_MAX_RETRIES:
-+ if (failures < args->suppress_info)
-+ report_info("Retried transaction %lu times without exception",
-+ args->max_retries);
-+ break;
-+ default:
-+ report_fail("Invalid return transaction result");
-+ goto out;
-+ }
-+
-+ if (failures < args->suppress_info)
-+ report_info("transaction abort code: %llu", diag.tdb.abort_code);
-+ if (args->diagnose && failures < args->suppress_info) {
++ register_pgm_cleanup_func(trigger->fixup);
++ trans_result = retry_transaction(trigger, args->max_retries, &diag.tdb, expected_pgm);
++ register_pgm_cleanup_func(NULL);
++ switch (trans_result) {
++ case 0:
++ report_pass("Program interrupt: expected(%d) == received(%d)",
++ expected_pgm, expected_pgm);
++ break;
++ case _HTM_TBEGIN_INDETERMINATE:
++ case _HTM_TBEGIN_PERSISTENT:
++ report_info("transaction failed with cc %d", trans_result);
++ report_info("transaction abort code: %llu", diag.tdb.abort_code);
++ if (args->diagnose)
+ for (i = 0; i < 32; i++)
-+ report_info("diag+%03d: %016lx", i*8, diag.dwords[i]);
-+ }
-+ ++failures;
-+ }
-+ if (failures <= args->max_failures) {
-+ report_pass(
-+ "Program interrupt: always expected(%d) == received(%d), transaction failures: %u",
-+ expected_pgm,
-+ expected_pgm,
-+ failures);
-+ } else {
-+ report_fail("Too many transaction failures: %u", failures);
++ report_info("diag+%03d: %016lx", i * 8, diag.dwords[i]);
++ break;
++ case _HTM_TBEGIN_TRANSIENT:
++ report_fail("Program interrupt: expected(%d) == received(%d)",
++ expected_pgm, clear_pgm_int());
++ break;
++ case TRANSACTION_COMPLETED:
++ report_fail("Transaction completed without exception");
++ break;
++ case TRANSACTION_MAX_RETRIES:
++ report_info("Retried transaction %lu times without exception",
++ args->max_retries);
++ break;
++ default:
++ report_fail("Invalid return transaction result");
++ break;
+ }
-+ if (failures > args->suppress_info)
-+ report_info("Suppressed some transaction failure information messages");
+
-+out:
+ ctl_clear_bit(0, CTL0_TRANSACT_EX_CTL);
+}
+
- static struct args parse_args(int argc, char **argv)
- {
- struct args args = {
- .iterations = 1,
++static struct args parse_args(int argc, char **argv)
++{
++ struct args args = {
+ .max_retries = 20,
-+ .suppress_info = 20,
+ .diagnose = false
- };
- unsigned int i;
- long arg;
-- bool no_arg;
-+ bool no_arg, max_failures = false;
- char *end;
-
- for (i = 1; i < argc; i++) {
-@@ s390x/spec_ex.c: static struct args parse_args(int argc, char **argv)
- report_abort("--iterations needs a positive parameter");
- args.iterations = arg;
- ++i;
-+ } else if (!strcmp("--max-retries", argv[i])) {
-+ if (no_arg)
-+ report_abort("--max-retries needs a positive parameter");
-+ args.max_retries = arg;
-+ ++i;
-+ } else if (!strcmp("--suppress-info", argv[i])) {
-+ if (no_arg)
-+ report_abort("--suppress-info needs a positive parameter");
-+ args.suppress_info = arg;
-+ ++i;
-+ } else if (!strcmp("--max-failures", argv[i])) {
++ };
++ unsigned int i;
++ long arg;
++ bool no_arg;
++ char *end;
++ const char *flag;
++ uint64_t *argp;
++
++ for (i = 1; i < argc; i++) {
++ no_arg = true;
++ if (i < argc - 1) {
++ no_arg = *argv[i + 1] == '\0';
++ arg = strtol(argv[i + 1], &end, 10);
++ no_arg |= *end != '\0';
++ no_arg |= arg < 0;
++ }
++
++ flag = "--max-retries";
++ argp = &args.max_retries;
++ if (!strcmp(flag, argv[i])) {
+ if (no_arg)
-+ report_abort("--max-failures needs a positive parameter");
-+ args.max_failures = arg;
-+ max_failures = true;
++ report_abort("%s needs a positive parameter", flag);
++ *argp = arg;
+ ++i;
-+ } else if (!strcmp("--diagnose", argv[i])) {
++ continue;
++ }
++ if (!strcmp("--diagnose", argv[i])) {
+ args.diagnose = true;
-+ } else if (!strcmp("--no-diagnose", argv[i])) {
++ continue;
++ }
++ if (!strcmp("--no-diagnose", argv[i])) {
+ args.diagnose = false;
- } else {
- report_abort("Unsupported parameter '%s'",
- argv[i]);
- }
- }
++ continue;
++ }
++ report_abort("Unsupported parameter '%s'",
++ argv[i]);
++ }
+
-+ if (!max_failures)
-+ args.max_failures = args.iterations / 1000;
++ return args;
++}
+
- return args;
- }
+ int main(int argc, char **argv)
+ {
+ unsigned int i;
++ struct args args = parse_args(argc, argv);
++
+ report_prefix_push("specification exception");
+ for (i = 0; spec_ex_triggers[i].name; i++) {
+ report_prefix_push(spec_ex_triggers[i].name);
@@ s390x/spec_ex.c: int main(int argc, char **argv)
}
report_prefix_pop();
base-commit: ca785dae0dd343b1de4b3f5d6c1223d41fbc39e7
--
2.33.1
next reply other threads:[~2022-01-11 16:39 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-11 16:38 Janis Schoetterl-Glausch [this message]
2022-01-11 16:39 ` [kvm-unit-tests PATCH v4 1/2] s390x: Add specification exception test Janis Schoetterl-Glausch
2022-01-13 7:56 ` Claudio Imbrenda
2022-01-13 12:36 ` Janis Schoetterl-Glausch
2022-01-11 16:39 ` [kvm-unit-tests PATCH v4 2/2] s390x: Test specification exceptions during transaction Janis Schoetterl-Glausch
2022-01-13 12:20 ` Claudio Imbrenda
2022-01-13 12:49 ` Janis Schoetterl-Glausch
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