Add a simple timer implementation for use in benchmarking.

test/src/timer.c

@@ -0,0 +1,57 @@
+#include "test/jemalloc_test.h"
+
+void
+timer_start(timer_t *timer)
+{
+
+	gettimeofday(&timer->tv0, NULL);
+}
+
+void
+timer_stop(timer_t *timer)
+{
+
+	gettimeofday(&timer->tv1, NULL);
+}
+
+uint64_t
+timer_usec(const timer_t *timer)
+{
+
+	return (((timer->tv1.tv_sec - timer->tv0.tv_sec) * 1000000) +
+	    timer->tv1.tv_usec - timer->tv0.tv_usec);
+}
+
+void
+timer_ratio(timer_t *a, timer_t *b, char *buf, size_t buflen)
+{
+	uint64_t t0 = timer_usec(a);
+	uint64_t t1 = timer_usec(b);
+	uint64_t mult;
+	unsigned i = 0;
+	unsigned j;
+	int n;
+
+	/* Whole. */
+	n = malloc_snprintf(&buf[i], buflen-i, "%"PRIu64, t0 / t1);
+	i += n;
+	if (i >= buflen)
+		return;
+	mult = 1;
+	for (j = 0; j < n; j++)
+		mult *= 10;
+
+	/* Decimal. */
+	n = malloc_snprintf(&buf[i], buflen-i, ".");
+	i += n;
+
+	/* Fraction. */
+	while (i < buflen-1) {
+		uint64_t round = (i+1 == buflen-1 && ((t0 * mult * 10 / t1) % 10
+		    >= 5)) ? 1 : 0;
+		n = malloc_snprintf(&buf[i], buflen-i,
+		    "%"PRIu64, (t0 * mult / t1) % 10 + round);
+		i += n;
+		mult *= 10;
+	}
+}