D1981.diff
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	Index: head/sys/kern/sched_ule.c
	===================================================================
	--- head/sys/kern/sched_ule.c
	+++ head/sys/kern/sched_ule.c
	@@ -360,17 +360,19 @@
	/*
	* We need some randomness. Implement the classic Linear Congruential
	* generator X_{n+1}=(aX_n+c) mod m. These values are optimized for
	- * m = 2^32, a = 69069 and c = 5. This is signed so that we can get
	- * both positive and negative values from it by shifting the value
	- * right.
	- */
	-static int sched_random(void)
	-{
	- int rnd, *rndptr;
	- rndptr = DPCPU_PTR(randomval);
	- rnd = rndptr 69069 + 5;
	- *rndptr = rnd;
	- return(rnd);
	+ * m = 2^32, a = 69069 and c = 5. We only return the upper 16 bits
	+ * of the random state (in the low bits of our answer) to return
	+ * the maximum randomness.
	+ */
	+static uint32_t
	+sched_random()
	+{
	+ uint32_t *rndptr;
	+
	+ rndptr = DPCPU_PTR(randomval);
	+ rndptr = rndptr * 69069 + 5;
	+
	+ return (*rndptr >> 16);
	}
	#endif

	@@ -718,7 +720,7 @@
	CPU_CLR(cpu, &cpumask);
	tdq = TDQ_CPU(cpu);
	load = tdq->tdq_load * 256;
	- rnd = sched_random() >> 26; /* -32 to +31 */
	+ rnd = sched_random() % 32;
	if (match & CPU_SEARCH_LOWEST) {
	if (cpu == low->cs_prefer)
	load -= 64;
	@@ -882,7 +884,7 @@
	return;

	balance_ticks = max(balance_interval / 2, 1) +
	- ((sched_random() >> 16) % balance_interval);
	+ (sched_random() % balance_interval);
	tdq = TDQ_SELF();
	TDQ_UNLOCK(tdq);
	sched_balance_group(cpu_top);