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Date:      Tue, 7 Jul 2015 15:22:29 +0000 (UTC)
From:      "Pedro F. Giffuni" <pfg@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org
Subject:   svn commit: r285243 - head/sys/kern
Message-ID:  <201507071522.t67FMTDP046123@repo.freebsd.org>

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Author: pfg
Date: Tue Jul  7 15:22:29 2015
New Revision: 285243
URL: https://svnweb.freebsd.org/changeset/base/285243

Log:
  Relocate sched_random() within the SMP section.
  
  Place sched_random nearer to where it's first used: moving the
  code nearer to where it  is used makes the code easier to read
  and we can reduce the initial "#ifdef SMP" island.
  
  Reword a little the comment and clean some whitespaces
  while here.

Modified:
  head/sys/kern/sched_ule.c

Modified: head/sys/kern/sched_ule.c
==============================================================================
--- head/sys/kern/sched_ule.c	Tue Jul  7 13:17:02 2015	(r285242)
+++ head/sys/kern/sched_ule.c	Tue Jul  7 15:22:29 2015	(r285243)
@@ -356,26 +356,6 @@ SDT_PROBE_DEFINE(sched, , , remain__cpu)
 SDT_PROBE_DEFINE2(sched, , , surrender, "struct thread *", 
     "struct proc *");
 
-#ifdef SMP
-/*
- * 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. 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(void) 
-{
-	uint32_t *rndptr;
-
-	rndptr = DPCPU_PTR(randomval);
-	*rndptr = *rndptr * 69069 + 5;
-
-	return (*rndptr >> 16);
-} 
-#endif
-
 /*
  * Print the threads waiting on a run-queue.
  */
@@ -625,6 +605,24 @@ tdq_setlowpri(struct tdq *tdq, struct th
 }
 
 #ifdef SMP
+/*
+ * We need some randomness. Implement a 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. We only return the upper 16 bits
+ * of the random state (in the low bits of our answer) to keep
+ * the maximum randomness.
+ */
+static uint32_t
+sched_random(void)
+{
+	uint32_t *rndptr;
+
+	rndptr = DPCPU_PTR(randomval);
+	*rndptr = *rndptr * 69069 + 5;
+
+	return (*rndptr >> 16);
+}
+
 struct cpu_search {
 	cpuset_t cs_mask;
 	u_int	cs_prefer;



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