[kvm-unit-tests PATCH v2 2/4] arm: pmu: Prepare for testing 64-bit overflows

[Ricardo Koller <ricarkol@google.com>]

PMUv3p5 adds a knob, PMCR_EL0.LP == 1, that allows overflowing at 64-bits
instead of 32. Prepare by doing these 3 things:

1. Add a "bool overflow_at_64bits" argument to all tests checking
   overflows.
2. Extend satisfy_prerequisites() to check if the machine supports
   "overflow_at_64bits".
3. Refactor the test invocations to use the new "run_test()" which adds a
   report prefix indicating whether the test uses 64 or 32-bit overflows.

A subsequent commit will actually add the 64-bit overflow tests.

Signed-off-by: Ricardo Koller <ricarkol@google.com>
---
 arm/pmu.c | 92 ++++++++++++++++++++++++++++++++-----------------------
 1 file changed, 53 insertions(+), 39 deletions(-)

diff --git a/arm/pmu.c b/arm/pmu.c
index 1b55e20..4cd3790 100644
--- a/arm/pmu.c
+++ b/arm/pmu.c
@@ -167,13 +167,13 @@ static void pmu_reset(void)
 /* event counter tests only implemented for aarch64 */
 static void test_event_introspection(void) {}
 static void test_event_counter_config(void) {}
-static void test_basic_event_count(void) {}
-static void test_mem_access(void) {}
-static void test_sw_incr(void) {}
-static void test_chained_counters(void) {}
-static void test_chained_sw_incr(void) {}
-static void test_chain_promotion(void) {}
-static void test_overflow_interrupt(void) {}
+static void test_basic_event_count(bool overflow_at_64bits) {}
+static void test_mem_access(bool overflow_at_64bits) {}
+static void test_sw_incr(bool overflow_at_64bits) {}
+static void test_chained_counters(bool unused) {}
+static void test_chained_sw_incr(bool unused) {}
+static void test_chain_promotion(bool unused) {}
+static void test_overflow_interrupt(bool overflow_at_64bits) {}
 
 #elif defined(__aarch64__)
 #define ID_AA64DFR0_PERFMON_SHIFT 8
@@ -419,16 +419,28 @@ static bool satisfy_prerequisites(uint32_t *events, unsigned int nb_events)
 			return false;
 		}
 	}
+
+	return true;
+}
+
+static bool check_overflow_prerequisites(bool overflow_at_64bits)
+{
+	if (overflow_at_64bits && pmu.version < ID_DFR0_PMU_V3_8_5) {
+		report_skip("Skip test as 64 overflows need FEAT_PMUv3p5");
+		return false;
+	}
+
 	return true;
 }
 
-static void test_basic_event_count(void)
+static void test_basic_event_count(bool overflow_at_64bits)
 {
 	uint32_t implemented_counter_mask, non_implemented_counter_mask;
 	uint32_t counter_mask;
 	uint32_t events[] = {CPU_CYCLES, INST_RETIRED};
 
-	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)))
+	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)) ||
+	    !check_overflow_prerequisites(overflow_at_64bits))
 		return;
 
 	implemented_counter_mask = BIT(pmu.nb_implemented_counters) - 1;
@@ -502,12 +514,13 @@ static void test_basic_event_count(void)
 		"check overflow happened on #0 only");
 }
 
-static void test_mem_access(void)
+static void test_mem_access(bool overflow_at_64bits)
 {
 	void *addr = malloc(PAGE_SIZE);
 	uint32_t events[] = {MEM_ACCESS, MEM_ACCESS};
 
-	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)))
+	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)) ||
+	    !check_overflow_prerequisites(overflow_at_64bits))
 		return;
 
 	pmu_reset();
@@ -538,13 +551,14 @@ static void test_mem_access(void)
 			read_sysreg(pmovsclr_el0));
 }
 
-static void test_sw_incr(void)
+static void test_sw_incr(bool overflow_at_64bits)
 {
 	uint32_t events[] = {SW_INCR, SW_INCR};
 	uint64_t cntr0;
 	int i;
 
-	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)))
+	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)) ||
+	    !check_overflow_prerequisites(overflow_at_64bits))
 		return;
 
 	pmu_reset();
@@ -587,7 +601,7 @@ static void test_sw_incr(void)
 		"overflow on counter #0 after 100 SW_INCR");
 }
 
-static void test_chained_counters(void)
+static void test_chained_counters(bool unused)
 {
 	uint32_t events[] = {CPU_CYCLES, CHAIN};
 	uint64_t all_set = ALL_SET_AT(pmu.version >= ID_DFR0_PMU_V3_8_5);
@@ -630,7 +644,7 @@ static void test_chained_counters(void)
 	report(read_sysreg(pmovsclr_el0) == 0x3, "overflow on even and odd counters");
 }
 
-static void test_chained_sw_incr(void)
+static void test_chained_sw_incr(bool unused)
 {
 	uint32_t events[] = {SW_INCR, CHAIN};
 	uint64_t cntr0, cntr1;
@@ -686,7 +700,7 @@ static void test_chained_sw_incr(void)
 		    read_regn_el0(pmevcntr, 0), read_regn_el0(pmevcntr, 1));
 }
 
-static void test_chain_promotion(void)
+static void test_chain_promotion(bool unused)
 {
 	uint32_t events[] = {MEM_ACCESS, CHAIN};
 	void *addr = malloc(PAGE_SIZE);
@@ -835,13 +849,14 @@ static bool expect_interrupts(uint32_t bitmap)
 	return true;
 }
 
-static void test_overflow_interrupt(void)
+static void test_overflow_interrupt(bool overflow_at_64bits)
 {
 	uint32_t events[] = {MEM_ACCESS, SW_INCR};
 	void *addr = malloc(PAGE_SIZE);
 	int i;
 
-	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)))
+	if (!satisfy_prerequisites(events, ARRAY_SIZE(events)) ||
+	    !check_overflow_prerequisites(overflow_at_64bits))
 		return;
 
 	gic_enable_defaults();
@@ -1065,6 +1080,19 @@ static bool pmu_probe(void)
 	return true;
 }
 
+static void run_test(char *name, void (*test)(bool), bool overflow_at_64bits)
+{
+	const char *prefix = overflow_at_64bits ? "64-bit overflows" : "32-bit overflows";
+
+	report_prefix_push(name);
+	report_prefix_push(prefix);
+
+	test(overflow_at_64bits);
+
+	report_prefix_pop();
+	report_prefix_pop();
+}
+
 int main(int argc, char *argv[])
 {
 	int cpi = 0;
@@ -1097,33 +1125,19 @@ int main(int argc, char *argv[])
 		test_event_counter_config();
 		report_prefix_pop();
 	} else if (strcmp(argv[1], "pmu-basic-event-count") == 0) {
-		report_prefix_push(argv[1]);
-		test_basic_event_count();
-		report_prefix_pop();
+		run_test(argv[1], test_basic_event_count, false);
 	} else if (strcmp(argv[1], "pmu-mem-access") == 0) {
-		report_prefix_push(argv[1]);
-		test_mem_access();
-		report_prefix_pop();
+		run_test(argv[1], test_mem_access, false);
 	} else if (strcmp(argv[1], "pmu-sw-incr") == 0) {
-		report_prefix_push(argv[1]);
-		test_sw_incr();
-		report_prefix_pop();
+		run_test(argv[1], test_sw_incr, false);
 	} else if (strcmp(argv[1], "pmu-chained-counters") == 0) {
-		report_prefix_push(argv[1]);
-		test_chained_counters();
-		report_prefix_pop();
+		run_test(argv[1], test_chained_counters, false);
 	} else if (strcmp(argv[1], "pmu-chained-sw-incr") == 0) {
-		report_prefix_push(argv[1]);
-		test_chained_sw_incr();
-		report_prefix_pop();
+		run_test(argv[1], test_chained_sw_incr, false);
 	} else if (strcmp(argv[1], "pmu-chain-promotion") == 0) {
-		report_prefix_push(argv[1]);
-		test_chain_promotion();
-		report_prefix_pop();
+		run_test(argv[1], test_chain_promotion, false);
 	} else if (strcmp(argv[1], "pmu-overflow-interrupt") == 0) {
-		report_prefix_push(argv[1]);
-		test_overflow_interrupt();
-		report_prefix_pop();
+		run_test(argv[1], test_overflow_interrupt, false);
 	} else {
 		report_abort("Unknown sub-test '%s'", argv[1]);
 	}
-- 
2.39.0.314.g84b9a713c41-goog