[kvm-unit-tests PATCH v2 7/8] arm64: microbench: Add time limit for each individual test

[Jingyi Wang <wangjingyi11@huawei.com>]

Besides using separate running times parameter, we add time limit
for loop_test to make sure each test should be done in a certain
time(5 sec here).

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
---
 arm/micro-bench.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 506d2f9..4c962b7 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -23,6 +23,7 @@
 #include <asm/gic-v3-its.h>
 
 #define NTIMES (1U << 16)
+#define MAX_NS (5 * 1000 * 1000 * 1000UL)
 
 static u32 cntfrq;
 
@@ -258,22 +259,26 @@ static void loop_test(struct exit_test *test)
 	uint64_t start, end, total_ticks, ntimes = 0;
 	struct ns_time total_ns, avg_ns;
 
+	total_ticks = 0;
 	if (test->prep) {
 		if(!test->prep()) {
 			printf("%s test skipped\n", test->name);
 			return;
 		}
 	}
-	isb();
-	start = read_sysreg(cntpct_el0);
-	while (ntimes < test->times) {
+
+	while (ntimes < test->times && total_ns.ns < MAX_NS) {
+		isb();
+		start = read_sysreg(cntpct_el0);
 		test->exec();
+		isb();
+		end = read_sysreg(cntpct_el0);
+
 		ntimes++;
+		total_ticks += (end - start);
+		ticks_to_ns_time(total_ticks, &total_ns);
 	}
-	isb();
-	end = read_sysreg(cntpct_el0);
 
-	total_ticks = end - start;
 	ticks_to_ns_time(total_ticks, &total_ns);
 	avg_ns.ns = total_ns.ns / ntimes;
 	avg_ns.ns_frac = total_ns.ns_frac / ntimes;
-- 
2.19.1