1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * mm_init.c - Memory initialisation verification and debugging
4 *
5 * Copyright 2008 IBM Corporation, 2008
6 * Author Mel Gorman <mel@csn.ul.ie>
7 *
8 */
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/kobject.h>
12 #include <linux/export.h>
13 #include <linux/memory.h>
14 #include <linux/notifier.h>
15 #include <linux/sched.h>
16 #include "internal.h"
17
18 #ifdef CONFIG_DEBUG_MEMORY_INIT
19 int __meminitdata mminit_loglevel;
20
21 #ifndef SECTIONS_SHIFT
22 #define SECTIONS_SHIFT 0
23 #endif
24
25 /* The zonelists are simply reported, validation is manual. */
mminit_verify_zonelist(void)26 void __init mminit_verify_zonelist(void)
27 {
28 int nid;
29
30 if (mminit_loglevel < MMINIT_VERIFY)
31 return;
32
33 for_each_online_node(nid) {
34 pg_data_t *pgdat = NODE_DATA(nid);
35 struct zone *zone;
36 struct zoneref *z;
37 struct zonelist *zonelist;
38 int i, listid, zoneid;
39
40 BUG_ON(MAX_ZONELISTS > 2);
41 for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
42
43 /* Identify the zone and nodelist */
44 zoneid = i % MAX_NR_ZONES;
45 listid = i / MAX_NR_ZONES;
46 zonelist = &pgdat->node_zonelists[listid];
47 zone = &pgdat->node_zones[zoneid];
48 if (!populated_zone(zone))
49 continue;
50
51 /* Print information about the zonelist */
52 printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
53 listid > 0 ? "thisnode" : "general", nid,
54 zone->name);
55
56 /* Iterate the zonelist */
57 for_each_zone_zonelist(zone, z, zonelist, zoneid)
58 pr_cont("%d:%s ", zone_to_nid(zone), zone->name);
59 pr_cont("\n");
60 }
61 }
62 }
63
mminit_verify_pageflags_layout(void)64 void __init mminit_verify_pageflags_layout(void)
65 {
66 int shift, width;
67 unsigned long or_mask, add_mask;
68
69 shift = 8 * sizeof(unsigned long);
70 width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH - LAST_CPUPID_SHIFT;
71 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
72 "Section %d Node %d Zone %d Lastcpupid %d Flags %d\n",
73 SECTIONS_WIDTH,
74 NODES_WIDTH,
75 ZONES_WIDTH,
76 LAST_CPUPID_WIDTH,
77 NR_PAGEFLAGS);
78 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
79 "Section %d Node %d Zone %d Lastcpupid %d\n",
80 SECTIONS_SHIFT,
81 NODES_SHIFT,
82 ZONES_SHIFT,
83 LAST_CPUPID_SHIFT);
84 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
85 "Section %lu Node %lu Zone %lu Lastcpupid %lu\n",
86 (unsigned long)SECTIONS_PGSHIFT,
87 (unsigned long)NODES_PGSHIFT,
88 (unsigned long)ZONES_PGSHIFT,
89 (unsigned long)LAST_CPUPID_PGSHIFT);
90 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
91 "Node/Zone ID: %lu -> %lu\n",
92 (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
93 (unsigned long)ZONEID_PGOFF);
94 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
95 "location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
96 shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
97 #ifdef NODE_NOT_IN_PAGE_FLAGS
98 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
99 "Node not in page flags");
100 #endif
101 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
102 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
103 "Last cpupid not in page flags");
104 #endif
105
106 if (SECTIONS_WIDTH) {
107 shift -= SECTIONS_WIDTH;
108 BUG_ON(shift != SECTIONS_PGSHIFT);
109 }
110 if (NODES_WIDTH) {
111 shift -= NODES_WIDTH;
112 BUG_ON(shift != NODES_PGSHIFT);
113 }
114 if (ZONES_WIDTH) {
115 shift -= ZONES_WIDTH;
116 BUG_ON(shift != ZONES_PGSHIFT);
117 }
118
119 /* Check for bitmask overlaps */
120 or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
121 (NODES_MASK << NODES_PGSHIFT) |
122 (SECTIONS_MASK << SECTIONS_PGSHIFT);
123 add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
124 (NODES_MASK << NODES_PGSHIFT) +
125 (SECTIONS_MASK << SECTIONS_PGSHIFT);
126 BUG_ON(or_mask != add_mask);
127 }
128
set_mminit_loglevel(char * str)129 static __init int set_mminit_loglevel(char *str)
130 {
131 get_option(&str, &mminit_loglevel);
132 return 0;
133 }
134 early_param("mminit_loglevel", set_mminit_loglevel);
135 #endif /* CONFIG_DEBUG_MEMORY_INIT */
136
137 struct kobject *mm_kobj;
138 EXPORT_SYMBOL_GPL(mm_kobj);
139
140 #ifdef CONFIG_SMP
141 s32 vm_committed_as_batch = 32;
142
mm_compute_batch(void)143 static void __meminit mm_compute_batch(void)
144 {
145 u64 memsized_batch;
146 s32 nr = num_present_cpus();
147 s32 batch = max_t(s32, nr*2, 32);
148
149 /* batch size set to 0.4% of (total memory/#cpus), or max int32 */
150 memsized_batch = min_t(u64, (totalram_pages()/nr)/256, 0x7fffffff);
151
152 vm_committed_as_batch = max_t(s32, memsized_batch, batch);
153 }
154
mm_compute_batch_notifier(struct notifier_block * self,unsigned long action,void * arg)155 static int __meminit mm_compute_batch_notifier(struct notifier_block *self,
156 unsigned long action, void *arg)
157 {
158 switch (action) {
159 case MEM_ONLINE:
160 case MEM_OFFLINE:
161 mm_compute_batch();
162 default:
163 break;
164 }
165 return NOTIFY_OK;
166 }
167
168 static struct notifier_block compute_batch_nb __meminitdata = {
169 .notifier_call = mm_compute_batch_notifier,
170 .priority = IPC_CALLBACK_PRI, /* use lowest priority */
171 };
172
mm_compute_batch_init(void)173 static int __init mm_compute_batch_init(void)
174 {
175 mm_compute_batch();
176 register_hotmemory_notifier(&compute_batch_nb);
177
178 return 0;
179 }
180
181 __initcall(mm_compute_batch_init);
182
183 #endif
184
mm_sysfs_init(void)185 static int __init mm_sysfs_init(void)
186 {
187 mm_kobj = kobject_create_and_add("mm", kernel_kobj);
188 if (!mm_kobj)
189 return -ENOMEM;
190
191 return 0;
192 }
193 postcore_initcall(mm_sysfs_init);
194
