xref: /linux/mm/mm_init.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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/export.h>
12 #include <linux/memory.h>
13 #include <linux/notifier.h>
14 #include "internal.h"
15 
16 #ifdef CONFIG_DEBUG_MEMORY_INIT
17 int __meminitdata mminit_loglevel;
18 
19 #ifndef SECTIONS_SHIFT
20 #define SECTIONS_SHIFT	0
21 #endif
22 
23 /* The zonelists are simply reported, validation is manual. */
24 void __init mminit_verify_zonelist(void)
25 {
26 	int nid;
27 
28 	if (mminit_loglevel < MMINIT_VERIFY)
29 		return;
30 
31 	for_each_online_node(nid) {
32 		pg_data_t *pgdat = NODE_DATA(nid);
33 		struct zone *zone;
34 		struct zoneref *z;
35 		struct zonelist *zonelist;
36 		int i, listid, zoneid;
37 
38 		BUG_ON(MAX_ZONELISTS > 2);
39 		for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
40 
41 			/* Identify the zone and nodelist */
42 			zoneid = i % MAX_NR_ZONES;
43 			listid = i / MAX_NR_ZONES;
44 			zonelist = &pgdat->node_zonelists[listid];
45 			zone = &pgdat->node_zones[zoneid];
46 			if (!populated_zone(zone))
47 				continue;
48 
49 			/* Print information about the zonelist */
50 			printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
51 				listid > 0 ? "thisnode" : "general", nid,
52 				zone->name);
53 
54 			/* Iterate the zonelist */
55 			for_each_zone_zonelist(zone, z, zonelist, zoneid) {
56 #ifdef CONFIG_NUMA
57 				printk(KERN_CONT "%d:%s ",
58 					zone->node, zone->name);
59 #else
60 				printk(KERN_CONT "0:%s ", zone->name);
61 #endif /* CONFIG_NUMA */
62 			}
63 			printk(KERN_CONT "\n");
64 		}
65 	}
66 }
67 
68 void __init mminit_verify_pageflags_layout(void)
69 {
70 	int shift, width;
71 	unsigned long or_mask, add_mask;
72 
73 	shift = 8 * sizeof(unsigned long);
74 	width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH - LAST_CPUPID_SHIFT;
75 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
76 		"Section %d Node %d Zone %d Lastcpupid %d Flags %d\n",
77 		SECTIONS_WIDTH,
78 		NODES_WIDTH,
79 		ZONES_WIDTH,
80 		LAST_CPUPID_WIDTH,
81 		NR_PAGEFLAGS);
82 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
83 		"Section %d Node %d Zone %d Lastcpupid %d\n",
84 		SECTIONS_SHIFT,
85 		NODES_SHIFT,
86 		ZONES_SHIFT,
87 		LAST_CPUPID_SHIFT);
88 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
89 		"Section %lu Node %lu Zone %lu Lastcpupid %lu\n",
90 		(unsigned long)SECTIONS_PGSHIFT,
91 		(unsigned long)NODES_PGSHIFT,
92 		(unsigned long)ZONES_PGSHIFT,
93 		(unsigned long)LAST_CPUPID_PGSHIFT);
94 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
95 		"Node/Zone ID: %lu -> %lu\n",
96 		(unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
97 		(unsigned long)ZONEID_PGOFF);
98 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
99 		"location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
100 		shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
101 #ifdef NODE_NOT_IN_PAGE_FLAGS
102 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
103 		"Node not in page flags");
104 #endif
105 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
106 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
107 		"Last cpupid not in page flags");
108 #endif
109 
110 	if (SECTIONS_WIDTH) {
111 		shift -= SECTIONS_WIDTH;
112 		BUG_ON(shift != SECTIONS_PGSHIFT);
113 	}
114 	if (NODES_WIDTH) {
115 		shift -= NODES_WIDTH;
116 		BUG_ON(shift != NODES_PGSHIFT);
117 	}
118 	if (ZONES_WIDTH) {
119 		shift -= ZONES_WIDTH;
120 		BUG_ON(shift != ZONES_PGSHIFT);
121 	}
122 
123 	/* Check for bitmask overlaps */
124 	or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
125 			(NODES_MASK << NODES_PGSHIFT) |
126 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
127 	add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
128 			(NODES_MASK << NODES_PGSHIFT) +
129 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
130 	BUG_ON(or_mask != add_mask);
131 }
132 
133 void __meminit mminit_verify_page_links(struct page *page, enum zone_type zone,
134 			unsigned long nid, unsigned long pfn)
135 {
136 	BUG_ON(page_to_nid(page) != nid);
137 	BUG_ON(page_zonenum(page) != zone);
138 	BUG_ON(page_to_pfn(page) != pfn);
139 }
140 
141 static __init int set_mminit_loglevel(char *str)
142 {
143 	get_option(&str, &mminit_loglevel);
144 	return 0;
145 }
146 early_param("mminit_loglevel", set_mminit_loglevel);
147 #endif /* CONFIG_DEBUG_MEMORY_INIT */
148 
149 struct kobject *mm_kobj;
150 EXPORT_SYMBOL_GPL(mm_kobj);
151 
152 #ifdef CONFIG_SMP
153 s32 vm_committed_as_batch = 32;
154 
155 static void __meminit mm_compute_batch(void)
156 {
157 	u64 memsized_batch;
158 	s32 nr = num_present_cpus();
159 	s32 batch = max_t(s32, nr*2, 32);
160 
161 	/* batch size set to 0.4% of (total memory/#cpus), or max int32 */
162 	memsized_batch = min_t(u64, (totalram_pages/nr)/256, 0x7fffffff);
163 
164 	vm_committed_as_batch = max_t(s32, memsized_batch, batch);
165 }
166 
167 static int __meminit mm_compute_batch_notifier(struct notifier_block *self,
168 					unsigned long action, void *arg)
169 {
170 	switch (action) {
171 	case MEM_ONLINE:
172 	case MEM_OFFLINE:
173 		mm_compute_batch();
174 	default:
175 		break;
176 	}
177 	return NOTIFY_OK;
178 }
179 
180 static struct notifier_block compute_batch_nb __meminitdata = {
181 	.notifier_call = mm_compute_batch_notifier,
182 	.priority = IPC_CALLBACK_PRI, /* use lowest priority */
183 };
184 
185 static int __init mm_compute_batch_init(void)
186 {
187 	mm_compute_batch();
188 	register_hotmemory_notifier(&compute_batch_nb);
189 
190 	return 0;
191 }
192 
193 __initcall(mm_compute_batch_init);
194 
195 #endif
196 
197 static int __init mm_sysfs_init(void)
198 {
199 	mm_kobj = kobject_create_and_add("mm", kernel_kobj);
200 	if (!mm_kobj)
201 		return -ENOMEM;
202 
203 	return 0;
204 }
205 postcore_initcall(mm_sysfs_init);
206