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