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 mminit_loglevel;
18
19 #ifndef SECTIONS_SHIFT
20 #define SECTIONS_SHIFT 0
21 #endif
22
23 /* The zonelists are simply reported, validation is manual. */
mminit_verify_zonelist(void)24 void 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
mminit_verify_pageflags_layout(void)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
mminit_verify_page_links(struct page * page,enum zone_type zone,unsigned long nid,unsigned long pfn)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
set_mminit_loglevel(char * str)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
mm_compute_batch(void)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
mm_compute_batch_notifier(struct notifier_block * self,unsigned long action,void * arg)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
mm_compute_batch_init(void)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
mm_sysfs_init(void)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