diff --git a/sys/alpha/include/runq.h b/sys/alpha/include/runq.h
index 3fc658afaa22..9f844b69fe5f 100644
--- a/sys/alpha/include/runq.h
+++ b/sys/alpha/include/runq.h
@@ -36,7 +36,7 @@
 #define	RQB_BIT(pri)	(1UL << ((pri) & (RQB_BPW - 1)))
 #define	RQB_WORD(pri)	((pri) >> RQB_L2BPW)
 
-#define	RQB_FFS(word)	(ffs64(word))
+#define	RQB_FFS(word)	(ffs64(word) - 1)
 
 /*
  * Type of run queue status word.
diff --git a/sys/amd64/include/runq.h b/sys/amd64/include/runq.h
index 1ea7735631bc..2a21bfa4ca29 100644
--- a/sys/amd64/include/runq.h
+++ b/sys/amd64/include/runq.h
@@ -36,7 +36,7 @@
 #define	RQB_BIT(pri)	(1 << ((pri) & (RQB_BPW - 1)))
 #define	RQB_WORD(pri)	((pri) >> RQB_L2BPW)
 
-#define	RQB_FFS(word)	(ffs(word))
+#define	RQB_FFS(word)	(ffs(word) - 1)
 
 /*
  * Type of run queue status word.
diff --git a/sys/i386/include/runq.h b/sys/i386/include/runq.h
index 1ea7735631bc..2a21bfa4ca29 100644
--- a/sys/i386/include/runq.h
+++ b/sys/i386/include/runq.h
@@ -36,7 +36,7 @@
 #define	RQB_BIT(pri)	(1 << ((pri) & (RQB_BPW - 1)))
 #define	RQB_WORD(pri)	((pri) >> RQB_L2BPW)
 
-#define	RQB_FFS(word)	(ffs(word))
+#define	RQB_FFS(word)	(ffs(word) - 1)
 
 /*
  * Type of run queue status word.
diff --git a/sys/ia64/include/runq.h b/sys/ia64/include/runq.h
index 3fc658afaa22..9f844b69fe5f 100644
--- a/sys/ia64/include/runq.h
+++ b/sys/ia64/include/runq.h
@@ -36,7 +36,7 @@
 #define	RQB_BIT(pri)	(1UL << ((pri) & (RQB_BPW - 1)))
 #define	RQB_WORD(pri)	((pri) >> RQB_L2BPW)
 
-#define	RQB_FFS(word)	(ffs64(word))
+#define	RQB_FFS(word)	(ffs64(word) - 1)
 
 /*
  * Type of run queue status word.
diff --git a/sys/kern/kern_switch.c b/sys/kern/kern_switch.c
index 2c6e6f62aa6c..2b531c0dae3d 100644
--- a/sys/kern/kern_switch.c
+++ b/sys/kern/kern_switch.c
@@ -129,8 +129,7 @@ runq_findbit(struct runq *rq)
 	rqb = &rq->rq_status;
 	for (i = 0; i < RQB_LEN; i++)
 		if (rqb->rqb_bits[i]) {
-			pri = (RQB_FFS(rqb->rqb_bits[i]) - 1) +
-			    (i << RQB_L2BPW);
+			pri = RQB_FFS(rqb->rqb_bits[i]) + (i << RQB_L2BPW);
 			CTR3(KTR_RUNQ, "runq_findbit: bits=%#x i=%d pri=%d",
 			    rqb->rqb_bits[i], i, pri);
 			return (pri);
diff --git a/sys/powerpc/include/runq.h b/sys/powerpc/include/runq.h
index 1ea7735631bc..2a21bfa4ca29 100644
--- a/sys/powerpc/include/runq.h
+++ b/sys/powerpc/include/runq.h
@@ -36,7 +36,7 @@
 #define	RQB_BIT(pri)	(1 << ((pri) & (RQB_BPW - 1)))
 #define	RQB_WORD(pri)	((pri) >> RQB_L2BPW)
 
-#define	RQB_FFS(word)	(ffs(word))
+#define	RQB_FFS(word)	(ffs(word) - 1)
 
 /*
  * Type of run queue status word.
diff --git a/sys/sparc64/include/runq.h b/sys/sparc64/include/runq.h
index 3fc658afaa22..9f844b69fe5f 100644
--- a/sys/sparc64/include/runq.h
+++ b/sys/sparc64/include/runq.h
@@ -36,7 +36,7 @@
 #define	RQB_BIT(pri)	(1UL << ((pri) & (RQB_BPW - 1)))
 #define	RQB_WORD(pri)	((pri) >> RQB_L2BPW)
 
-#define	RQB_FFS(word)	(ffs64(word))
+#define	RQB_FFS(word)	(ffs64(word) - 1)
 
 /*
  * Type of run queue status word.