Index: sys/pool.h
===================================================================
RCS file: /cvs/src/sys/sys/pool.h,v
retrieving revision 1.54
diff -u -p -r1.54 pool.h
--- sys/pool.h	1 Nov 2014 23:58:07 -0000	1.54
+++ sys/pool.h	5 Nov 2014 23:31:17 -0000
@@ -128,6 +128,7 @@ struct pool {
 	RB_HEAD(phtree, pool_item_header)
 			pr_phtree;
 
+	u_int		pr_maxcolors;	/* Cache colouring */
 	int		pr_phoffset;	/* Offset in page of page header */
 
 	/*
Index: kern/subr_pool.c
===================================================================
RCS file: /cvs/src/sys/kern/subr_pool.c,v
retrieving revision 1.164
diff -u -p -r1.164 subr_pool.c
--- kern/subr_pool.c	1 Nov 2014 23:58:07 -0000	1.164
+++ kern/subr_pool.c	5 Nov 2014 23:31:17 -0000
@@ -82,6 +82,7 @@ struct pool_item_header {
 				ph_node;	/* Off-page page headers */
 	int			ph_nmissing;	/* # of chunks in use */
 	caddr_t			ph_page;	/* this page's address */
+	caddr_t			ph_colored;	/* page's colored address */
 	u_long			ph_magic;
 };
 #define POOL_MAGICBIT (1 << 3) /* keep away from perturbed low bits */
@@ -216,7 +217,7 @@ void
 pool_init(struct pool *pp, size_t size, u_int align, u_int ioff, int flags,
     const char *wchan, struct pool_allocator *palloc)
 {
-	int off = 0;
+	int off = 0, space;
 	unsigned int pgsize = PAGE_SIZE, items;
 #ifdef DIAGNOSTIC
 	struct pool *iter;
@@ -292,6 +293,14 @@ pool_init(struct pool *pp, size_t size, 
 	pp->pr_hardlimit_warning_last.tv_usec = 0;
 	RB_INIT(&pp->pr_phtree);
 
+	/*
+	 * Use the space between the chunks and the page header
+	 * for "cache coloring".
+	 */
+	space = POOL_INPGHDR(pp) ? pp->pr_phoffset : pp->pr_pgsize;
+	space -= pp->pr_itemsperpage * pp->pr_size;
+	pp->pr_maxcolors = (space / align) + 1;
+
 	pp->pr_nget = 0;
 	pp->pr_nfail = 0;
 	pp->pr_nput = 0;
@@ -740,6 +749,8 @@ pool_p_alloc(struct pool *pp, int flags)
 
 	XSIMPLEQ_INIT(&ph->ph_itemlist);
 	ph->ph_page = addr;
+	addr += pp->pr_align * (pp->pr_npagealloc % pp->pr_maxcolors);
+	ph->ph_colored = addr;
 	ph->ph_nmissing = 0;
 	arc4random_buf(&ph->ph_magic, sizeof(ph->ph_magic));
 #ifdef DIAGNOSTIC
@@ -986,8 +997,8 @@ pool_print_pagelist(struct pool_pagelist
 	struct pool_item *pi;
 
 	LIST_FOREACH(ph, pl, ph_pagelist) {
-		(*pr)("\t\tpage %p, nmissing %d\n",
-		    ph->ph_page, ph->ph_nmissing);
+		(*pr)("\t\tpage %p, color %p, nmissing %d\n",
+		    ph->ph_page, ph->ph_colored, ph->ph_nmissing);
 		XSIMPLEQ_FOREACH(pi, &ph->ph_itemlist, pi_list) {
 			if (pi->pi_magic != POOL_IMAGIC(ph, pi)) {
 				(*pr)("\t\t\titem %p, magic 0x%lx\n",
@@ -1011,8 +1022,8 @@ pool_print1(struct pool *pp, const char 
 		modif++;
 	}
 
-	(*pr)("POOL %s: size %u, align %u, roflags 0x%08x\n",
-	    pp->pr_wchan, pp->pr_size, pp->pr_align,
+	(*pr)("POOL %s: size %u, align %u, maxcolors %u, roflags 0x%08x\n",
+	    pp->pr_wchan, pp->pr_size, pp->pr_align, pp->pr_maxcolors,
 	    pp->pr_roflags);
 	(*pr)("\talloc %p\n", pp->pr_alloc);
 	(*pr)("\tminitems %u, minpages %u, maxpages %u, npages %u\n",
@@ -1222,7 +1233,7 @@ pool_walk(struct pool *pp, int full,
 	int n;
 
 	LIST_FOREACH(ph, &pp->pr_fullpages, ph_pagelist) {
-		cp = ph->ph_page;
+		cp = ph->ph_colored;
 		n = ph->ph_nmissing;
 
 		while (n--) {
@@ -1232,7 +1243,7 @@ pool_walk(struct pool *pp, int full,
 	}
 
 	LIST_FOREACH(ph, &pp->pr_partpages, ph_pagelist) {
-		cp = ph->ph_page;
+		cp = ph->ph_colored;
 		n = ph->ph_nmissing;
 
 		do {