Index: subr_pool.c
===================================================================
RCS file: /cvs/src/sys/kern/subr_pool.c,v
retrieving revision 1.165
diff -u -p -r1.165 subr_pool.c
--- subr_pool.c	10 Nov 2014 18:55:43 -0000	1.165
+++ subr_pool.c	14 Nov 2014 02:32:43 -0000
@@ -105,13 +105,13 @@ int	pool_debug = 0;
 #define POOL_INPGHDR(pp) ((pp)->pr_phoffset != 0)
 
 struct pool_item_header *
-	 pool_p_alloc(struct pool *, int);
+	 pool_p_alloc(struct pool *, int, int *);
 void	 pool_p_insert(struct pool *, struct pool_item_header *);
 void	 pool_p_remove(struct pool *, struct pool_item_header *);
 void	 pool_p_free(struct pool *, struct pool_item_header *);
 
 void	 pool_update_curpage(struct pool *);
-void	*pool_do_get(struct pool *, int);
+void	*pool_do_get(struct pool *, int, int *);
 int	 pool_chk_page(struct pool *, struct pool_item_header *, int);
 int	 pool_chk(struct pool *);
 void	 pool_get_done(void *, void *);
@@ -416,6 +416,7 @@ void *
 pool_get(struct pool *pp, int flags)
 {
 	void *v = NULL;
+	int slowdown = 0;
 
 	KASSERT(flags & (PR_WAITOK | PR_NOWAIT));
 
@@ -424,12 +425,15 @@ pool_get(struct pool *pp, int flags)
 	if (pp->pr_nout >= pp->pr_hardlimit) {
 		if (ISSET(flags, PR_NOWAIT|PR_LIMITFAIL))
 			goto fail;
-	} else if ((v = pool_do_get(pp, flags)) == NULL) {
+	} else if ((v = pool_do_get(pp, flags, &slowdown)) == NULL) {
 		if (ISSET(flags, PR_NOWAIT))
 			goto fail;
 	}
 	mtx_leave(&pp->pr_mtx);
 
+	if (slowdown && ISSET(flags, PR_WAITOK))
+		yield();
+
 	if (v == NULL) {
 		struct pool_get_memory mem =
 		    { MUTEX_INITIALIZER(pp->pr_ipl), NULL };
@@ -497,11 +501,13 @@ pool_runqueue(struct pool *pp, int flags
 		mtx_enter(&pp->pr_mtx);
 		pr = TAILQ_FIRST(&prl);
 		while (pr != NULL) {
+			int slowdown = 0;
+
 			if (pp->pr_nout >= pp->pr_hardlimit)
 				break;
 
-			pr->pr_item = pool_do_get(pp, flags);
-			if (pr->pr_item == NULL)
+			pr->pr_item = pool_do_get(pp, flags, &slowdown);
+			if (pr->pr_item == NULL) /* || slowdown ? */
 				break;
 
 			pr = TAILQ_NEXT(pr, pr_entry);
@@ -525,7 +531,7 @@ pool_runqueue(struct pool *pp, int flags
 }
 
 void *
-pool_do_get(struct pool *pp, int flags)
+pool_do_get(struct pool *pp, int flags, int *slowdown)
 {
 	struct pool_item *pi;
 	struct pool_item_header *ph;
@@ -540,7 +546,7 @@ pool_do_get(struct pool *pp, int flags)
 
 	if (pp->pr_curpage == NULL) {
 		mtx_leave(&pp->pr_mtx);
-		ph = pool_p_alloc(pp, flags);
+		ph = pool_p_alloc(pp, flags, slowdown);
 		mtx_enter(&pp->pr_mtx);
 
 		if (ph == NULL) {
@@ -693,8 +699,10 @@ pool_prime(struct pool *pp, int n)
 	newpages = roundup(n, pp->pr_itemsperpage) / pp->pr_itemsperpage;
 
 	while (newpages-- > 0) {
-		ph = pool_p_alloc(pp, PR_NOWAIT);
-		if (ph == NULL)
+		int slowdown = 0;
+
+		ph = pool_p_alloc(pp, PR_NOWAIT, &slowdown);
+		if (ph == NULL) /* or slowdown? */
 			break;
 
 		LIST_INSERT_HEAD(&pl, ph, ph_pagelist);
@@ -711,22 +719,19 @@ pool_prime(struct pool *pp, int n)
 }
 
 struct pool_item_header *
-pool_p_alloc(struct pool *pp, int flags)
+pool_p_alloc(struct pool *pp, int flags, int *slowdown)
 {
 	struct pool_item_header *ph;
 	struct pool_item *pi;
 	caddr_t addr;
-	int n, slowdown = 0;
+	int n;
 
 	MUTEX_ASSERT_UNLOCKED(&pp->pr_mtx);
 	KASSERT(pp->pr_size >= sizeof(*pi));
 
-	addr = pool_allocator_alloc(pp, flags, &slowdown);
+	addr = pool_allocator_alloc(pp, flags, slowdown);
 	if (addr == NULL)
 		return (NULL);
-
-	if (slowdown && ISSET(flags, PR_WAITOK))
-		yield();
 
 	if (POOL_INPGHDR(pp))
 		ph = (struct pool_item_header *)(addr + pp->pr_phoffset);