1/*
2 * mm_init.c - Memory initialisation verification and debugging
3 *
4 * Copyright 2008 IBM Corporation, 2008
5 * Author Mel Gorman <mel@csn.ul.ie>
6 *
7 */
8#include <linux/kernel.h>
9#include <linux/init.h>
10#include <linux/kobject.h>
11#include <linux/module.h>
12#include "internal.h"
13
14#ifdef CONFIG_DEBUG_MEMORY_INIT
15int mminit_loglevel;
16
17#ifndef SECTIONS_SHIFT
18#define SECTIONS_SHIFT	0
19#endif
20
21/* The zonelists are simply reported, validation is manual. */
22void mminit_verify_zonelist(void)
23{
24	int nid;
25
26	if (mminit_loglevel < MMINIT_VERIFY)
27		return;
28
29	for_each_online_node(nid) {
30		pg_data_t *pgdat = NODE_DATA(nid);
31		struct zone *zone;
32		struct zoneref *z;
33		struct zonelist *zonelist;
34		int i, listid, zoneid;
35
36		BUG_ON(MAX_ZONELISTS > 2);
37		for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
38
39			/* Identify the zone and nodelist */
40			zoneid = i % MAX_NR_ZONES;
41			listid = i / MAX_NR_ZONES;
42			zonelist = &pgdat->node_zonelists[listid];
43			zone = &pgdat->node_zones[zoneid];
44			if (!populated_zone(zone))
45				continue;
46
47			/* Print information about the zonelist */
48			printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
49				listid > 0 ? "thisnode" : "general", nid,
50				zone->name);
51
52			/* Iterate the zonelist */
53			for_each_zone_zonelist(zone, z, zonelist, zoneid) {
54#ifdef CONFIG_NUMA
55				printk(KERN_CONT "%d:%s ",
56					zone->node, zone->name);
57#else
58				printk(KERN_CONT "0:%s ", zone->name);
59#endif /* CONFIG_NUMA */
60			}
61			printk(KERN_CONT "\n");
62		}
63	}
64}
65
66void __init mminit_verify_pageflags_layout(void)
67{
68	int shift, width;
69	unsigned long or_mask, add_mask;
70
71	shift = 8 * sizeof(unsigned long);
72	width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH;
73	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
74		"Section %d Node %d Zone %d Flags %d\n",
75		SECTIONS_WIDTH,
76		NODES_WIDTH,
77		ZONES_WIDTH,
78		NR_PAGEFLAGS);
79	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
80		"Section %d Node %d Zone %d\n",
81		SECTIONS_SHIFT,
82		NODES_SHIFT,
83		ZONES_SHIFT);
84	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_offsets",
85		"Section %lu Node %lu Zone %lu\n",
86		(unsigned long)SECTIONS_PGSHIFT,
87		(unsigned long)NODES_PGSHIFT,
88		(unsigned long)ZONES_PGSHIFT);
89	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_zoneid",
90		"Zone ID: %lu -> %lu\n",
91		(unsigned long)ZONEID_PGOFF,
92		(unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT));
93	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
94		"location: %d -> %d unused %d -> %d flags %d -> %d\n",
95		shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
96#ifdef NODE_NOT_IN_PAGE_FLAGS
97	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
98		"Node not in page flags");
99#endif
100
101	if (SECTIONS_WIDTH) {
102		shift -= SECTIONS_WIDTH;
103		BUG_ON(shift != SECTIONS_PGSHIFT);
104	}
105	if (NODES_WIDTH) {
106		shift -= NODES_WIDTH;
107		BUG_ON(shift != NODES_PGSHIFT);
108	}
109	if (ZONES_WIDTH) {
110		shift -= ZONES_WIDTH;
111		BUG_ON(shift != ZONES_PGSHIFT);
112	}
113
114	/* Check for bitmask overlaps */
115	or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
116			(NODES_MASK << NODES_PGSHIFT) |
117			(SECTIONS_MASK << SECTIONS_PGSHIFT);
118	add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
119			(NODES_MASK << NODES_PGSHIFT) +
120			(SECTIONS_MASK << SECTIONS_PGSHIFT);
121	BUG_ON(or_mask != add_mask);
122}
123
124void __meminit mminit_verify_page_links(struct page *page, enum zone_type zone,
125			unsigned long nid, unsigned long pfn)
126{
127	BUG_ON(page_to_nid(page) != nid);
128	BUG_ON(page_zonenum(page) != zone);
129	BUG_ON(page_to_pfn(page) != pfn);
130}
131
132static __init int set_mminit_loglevel(char *str)
133{
134	get_option(&str, &mminit_loglevel);
135	return 0;
136}
137early_param("mminit_loglevel", set_mminit_loglevel);
138#endif /* CONFIG_DEBUG_MEMORY_INIT */
139
140struct kobject *mm_kobj;
141EXPORT_SYMBOL_GPL(mm_kobj);
142
143static int __init mm_sysfs_init(void)
144{
145	mm_kobj = kobject_create_and_add("mm", kernel_kobj);
146	if (!mm_kobj)
147		return -ENOMEM;
148
149	return 0;
150}
151
152__initcall(mm_sysfs_init);
153