Line data Source code
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 <linux/mman.h>
17 : #include "internal.h"
18 :
19 : #ifdef CONFIG_DEBUG_MEMORY_INIT
20 : int __meminitdata mminit_loglevel;
21 :
22 : /* The zonelists are simply reported, validation is manual. */
23 1 : void __init mminit_verify_zonelist(void)
24 : {
25 : int nid;
26 :
27 1 : if (mminit_loglevel < MMINIT_VERIFY)
28 : return;
29 :
30 0 : for_each_online_node(nid) {
31 : pg_data_t *pgdat = NODE_DATA(nid);
32 : struct zone *zone;
33 : struct zoneref *z;
34 : struct zonelist *zonelist;
35 : int i, listid, zoneid;
36 :
37 : BUILD_BUG_ON(MAX_ZONELISTS > 2);
38 0 : for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
39 :
40 : /* Identify the zone and nodelist */
41 0 : zoneid = i % MAX_NR_ZONES;
42 0 : listid = i / MAX_NR_ZONES;
43 0 : zonelist = &pgdat->node_zonelists[listid];
44 0 : zone = &pgdat->node_zones[zoneid];
45 0 : if (!populated_zone(zone))
46 0 : continue;
47 :
48 : /* Print information about the zonelist */
49 0 : printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
50 : listid > 0 ? "thisnode" : "general", nid,
51 : zone->name);
52 :
53 : /* Iterate the zonelist */
54 0 : for_each_zone_zonelist(zone, z, zonelist, zoneid)
55 0 : pr_cont("%d:%s ", zone_to_nid(zone), zone->name);
56 0 : pr_cont("\n");
57 : }
58 : }
59 : }
60 :
61 1 : void __init mminit_verify_pageflags_layout(void)
62 : {
63 : int shift, width;
64 : unsigned long or_mask, add_mask;
65 :
66 1 : shift = 8 * sizeof(unsigned long);
67 1 : width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH
68 : - LAST_CPUPID_SHIFT - KASAN_TAG_WIDTH;
69 1 : mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
70 : "Section %d Node %d Zone %d Lastcpupid %d Kasantag %d Flags %d\n",
71 : SECTIONS_WIDTH,
72 : NODES_WIDTH,
73 : ZONES_WIDTH,
74 : LAST_CPUPID_WIDTH,
75 : KASAN_TAG_WIDTH,
76 : NR_PAGEFLAGS);
77 1 : mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
78 : "Section %d Node %d Zone %d Lastcpupid %d Kasantag %d\n",
79 : SECTIONS_SHIFT,
80 : NODES_SHIFT,
81 : ZONES_SHIFT,
82 : LAST_CPUPID_SHIFT,
83 : KASAN_TAG_WIDTH);
84 1 : mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
85 : "Section %lu Node %lu Zone %lu Lastcpupid %lu Kasantag %lu\n",
86 : (unsigned long)SECTIONS_PGSHIFT,
87 : (unsigned long)NODES_PGSHIFT,
88 : (unsigned long)ZONES_PGSHIFT,
89 : (unsigned long)LAST_CPUPID_PGSHIFT,
90 : (unsigned long)KASAN_TAG_PGSHIFT);
91 1 : mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
92 : "Node/Zone ID: %lu -> %lu\n",
93 : (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
94 : (unsigned long)ZONEID_PGOFF);
95 1 : mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
96 : "location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
97 : shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
98 : #ifdef NODE_NOT_IN_PAGE_FLAGS
99 : mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
100 : "Node not in page flags");
101 : #endif
102 : #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
103 : mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
104 : "Last cpupid not in page flags");
105 : #endif
106 :
107 : if (SECTIONS_WIDTH) {
108 : shift -= SECTIONS_WIDTH;
109 : BUG_ON(shift != SECTIONS_PGSHIFT);
110 : }
111 : if (NODES_WIDTH) {
112 : shift -= NODES_WIDTH;
113 : BUG_ON(shift != NODES_PGSHIFT);
114 : }
115 : if (ZONES_WIDTH) {
116 1 : shift -= ZONES_WIDTH;
117 : BUG_ON(shift != ZONES_PGSHIFT);
118 : }
119 :
120 : /* Check for bitmask overlaps */
121 1 : or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
122 : (NODES_MASK << NODES_PGSHIFT) |
123 : (SECTIONS_MASK << SECTIONS_PGSHIFT);
124 1 : add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
125 : (NODES_MASK << NODES_PGSHIFT) +
126 : (SECTIONS_MASK << SECTIONS_PGSHIFT);
127 : BUG_ON(or_mask != add_mask);
128 1 : }
129 :
130 0 : static __init int set_mminit_loglevel(char *str)
131 : {
132 0 : get_option(&str, &mminit_loglevel);
133 0 : return 0;
134 : }
135 : early_param("mminit_loglevel", set_mminit_loglevel);
136 : #endif /* CONFIG_DEBUG_MEMORY_INIT */
137 :
138 : struct kobject *mm_kobj;
139 : EXPORT_SYMBOL_GPL(mm_kobj);
140 :
141 : #ifdef CONFIG_SMP
142 : s32 vm_committed_as_batch = 32;
143 :
144 : void mm_compute_batch(int overcommit_policy)
145 : {
146 : u64 memsized_batch;
147 : s32 nr = num_present_cpus();
148 : s32 batch = max_t(s32, nr*2, 32);
149 : unsigned long ram_pages = totalram_pages();
150 :
151 : /*
152 : * For policy OVERCOMMIT_NEVER, set batch size to 0.4% of
153 : * (total memory/#cpus), and lift it to 25% for other policies
154 : * to easy the possible lock contention for percpu_counter
155 : * vm_committed_as, while the max limit is INT_MAX
156 : */
157 : if (overcommit_policy == OVERCOMMIT_NEVER)
158 : memsized_batch = min_t(u64, ram_pages/nr/256, INT_MAX);
159 : else
160 : memsized_batch = min_t(u64, ram_pages/nr/4, INT_MAX);
161 :
162 : vm_committed_as_batch = max_t(s32, memsized_batch, batch);
163 : }
164 :
165 : static int __meminit mm_compute_batch_notifier(struct notifier_block *self,
166 : unsigned long action, void *arg)
167 : {
168 : switch (action) {
169 : case MEM_ONLINE:
170 : case MEM_OFFLINE:
171 : mm_compute_batch(sysctl_overcommit_memory);
172 : break;
173 : default:
174 : break;
175 : }
176 : return NOTIFY_OK;
177 : }
178 :
179 : static struct notifier_block compute_batch_nb __meminitdata = {
180 : .notifier_call = mm_compute_batch_notifier,
181 : .priority = IPC_CALLBACK_PRI, /* use lowest priority */
182 : };
183 :
184 : static int __init mm_compute_batch_init(void)
185 : {
186 : mm_compute_batch(sysctl_overcommit_memory);
187 : register_hotmemory_notifier(&compute_batch_nb);
188 :
189 : return 0;
190 : }
191 :
192 : __initcall(mm_compute_batch_init);
193 :
194 : #endif
195 :
196 1 : static int __init mm_sysfs_init(void)
197 : {
198 1 : mm_kobj = kobject_create_and_add("mm", kernel_kobj);
199 1 : if (!mm_kobj)
200 : return -ENOMEM;
201 :
202 1 : return 0;
203 : }
204 : postcore_initcall(mm_sysfs_init);
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