Loading...
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
20int __meminitdata mminit_loglevel;
21
22#ifndef SECTIONS_SHIFT
23#define SECTIONS_SHIFT 0
24#endif
25
26/* The zonelists are simply reported, validation is manual. */
27void __init mminit_verify_zonelist(void)
28{
29 int nid;
30
31 if (mminit_loglevel < MMINIT_VERIFY)
32 return;
33
34 for_each_online_node(nid) {
35 pg_data_t *pgdat = NODE_DATA(nid);
36 struct zone *zone;
37 struct zoneref *z;
38 struct zonelist *zonelist;
39 int i, listid, zoneid;
40
41 BUILD_BUG_ON(MAX_ZONELISTS > 2);
42 for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
43
44 /* Identify the zone and nodelist */
45 zoneid = i % MAX_NR_ZONES;
46 listid = i / MAX_NR_ZONES;
47 zonelist = &pgdat->node_zonelists[listid];
48 zone = &pgdat->node_zones[zoneid];
49 if (!populated_zone(zone))
50 continue;
51
52 /* Print information about the zonelist */
53 printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
54 listid > 0 ? "thisnode" : "general", nid,
55 zone->name);
56
57 /* Iterate the zonelist */
58 for_each_zone_zonelist(zone, z, zonelist, zoneid)
59 pr_cont("%d:%s ", zone_to_nid(zone), zone->name);
60 pr_cont("\n");
61 }
62 }
63}
64
65void __init mminit_verify_pageflags_layout(void)
66{
67 int shift, width;
68 unsigned long or_mask, add_mask;
69
70 shift = 8 * sizeof(unsigned long);
71 width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH
72 - LAST_CPUPID_SHIFT - KASAN_TAG_WIDTH;
73 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
74 "Section %d Node %d Zone %d Lastcpupid %d Kasantag %d Flags %d\n",
75 SECTIONS_WIDTH,
76 NODES_WIDTH,
77 ZONES_WIDTH,
78 LAST_CPUPID_WIDTH,
79 KASAN_TAG_WIDTH,
80 NR_PAGEFLAGS);
81 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
82 "Section %d Node %d Zone %d Lastcpupid %d Kasantag %d\n",
83 SECTIONS_SHIFT,
84 NODES_SHIFT,
85 ZONES_SHIFT,
86 LAST_CPUPID_SHIFT,
87 KASAN_TAG_WIDTH);
88 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
89 "Section %lu Node %lu Zone %lu Lastcpupid %lu Kasantag %lu\n",
90 (unsigned long)SECTIONS_PGSHIFT,
91 (unsigned long)NODES_PGSHIFT,
92 (unsigned long)ZONES_PGSHIFT,
93 (unsigned long)LAST_CPUPID_PGSHIFT,
94 (unsigned long)KASAN_TAG_PGSHIFT);
95 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
96 "Node/Zone ID: %lu -> %lu\n",
97 (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
98 (unsigned long)ZONEID_PGOFF);
99 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
100 "location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
101 shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
102#ifdef NODE_NOT_IN_PAGE_FLAGS
103 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
104 "Node not in page flags");
105#endif
106#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
107 mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
108 "Last cpupid not in page flags");
109#endif
110
111 if (SECTIONS_WIDTH) {
112 shift -= SECTIONS_WIDTH;
113 BUG_ON(shift != SECTIONS_PGSHIFT);
114 }
115 if (NODES_WIDTH) {
116 shift -= NODES_WIDTH;
117 BUG_ON(shift != NODES_PGSHIFT);
118 }
119 if (ZONES_WIDTH) {
120 shift -= ZONES_WIDTH;
121 BUG_ON(shift != ZONES_PGSHIFT);
122 }
123
124 /* Check for bitmask overlaps */
125 or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
126 (NODES_MASK << NODES_PGSHIFT) |
127 (SECTIONS_MASK << SECTIONS_PGSHIFT);
128 add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
129 (NODES_MASK << NODES_PGSHIFT) +
130 (SECTIONS_MASK << SECTIONS_PGSHIFT);
131 BUG_ON(or_mask != add_mask);
132}
133
134static __init int set_mminit_loglevel(char *str)
135{
136 get_option(&str, &mminit_loglevel);
137 return 0;
138}
139early_param("mminit_loglevel", set_mminit_loglevel);
140#endif /* CONFIG_DEBUG_MEMORY_INIT */
141
142struct kobject *mm_kobj;
143EXPORT_SYMBOL_GPL(mm_kobj);
144
145#ifdef CONFIG_SMP
146s32 vm_committed_as_batch = 32;
147
148void mm_compute_batch(int overcommit_policy)
149{
150 u64 memsized_batch;
151 s32 nr = num_present_cpus();
152 s32 batch = max_t(s32, nr*2, 32);
153 unsigned long ram_pages = totalram_pages();
154
155 /*
156 * For policy OVERCOMMIT_NEVER, set batch size to 0.4% of
157 * (total memory/#cpus), and lift it to 25% for other policies
158 * to easy the possible lock contention for percpu_counter
159 * vm_committed_as, while the max limit is INT_MAX
160 */
161 if (overcommit_policy == OVERCOMMIT_NEVER)
162 memsized_batch = min_t(u64, ram_pages/nr/256, INT_MAX);
163 else
164 memsized_batch = min_t(u64, ram_pages/nr/4, INT_MAX);
165
166 vm_committed_as_batch = max_t(s32, memsized_batch, batch);
167}
168
169static int __meminit mm_compute_batch_notifier(struct notifier_block *self,
170 unsigned long action, void *arg)
171{
172 switch (action) {
173 case MEM_ONLINE:
174 case MEM_OFFLINE:
175 mm_compute_batch(sysctl_overcommit_memory);
176 default:
177 break;
178 }
179 return NOTIFY_OK;
180}
181
182static struct notifier_block compute_batch_nb __meminitdata = {
183 .notifier_call = mm_compute_batch_notifier,
184 .priority = IPC_CALLBACK_PRI, /* use lowest priority */
185};
186
187static int __init mm_compute_batch_init(void)
188{
189 mm_compute_batch(sysctl_overcommit_memory);
190 register_hotmemory_notifier(&compute_batch_nb);
191
192 return 0;
193}
194
195__initcall(mm_compute_batch_init);
196
197#endif
198
199static int __init mm_sysfs_init(void)
200{
201 mm_kobj = kobject_create_and_add("mm", kernel_kobj);
202 if (!mm_kobj)
203 return -ENOMEM;
204
205 return 0;
206}
207postcore_initcall(mm_sysfs_init);
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
20int __meminitdata mminit_loglevel;
21
22/* The zonelists are simply reported, validation is manual. */
23void __init mminit_verify_zonelist(void)
24{
25 int nid;
26
27 if (mminit_loglevel < MMINIT_VERIFY)
28 return;
29
30 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 for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
39
40 /* Identify the zone and nodelist */
41 zoneid = i % MAX_NR_ZONES;
42 listid = i / MAX_NR_ZONES;
43 zonelist = &pgdat->node_zonelists[listid];
44 zone = &pgdat->node_zones[zoneid];
45 if (!populated_zone(zone))
46 continue;
47
48 /* Print information about the zonelist */
49 printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
50 listid > 0 ? "thisnode" : "general", nid,
51 zone->name);
52
53 /* Iterate the zonelist */
54 for_each_zone_zonelist(zone, z, zonelist, zoneid)
55 pr_cont("%d:%s ", zone_to_nid(zone), zone->name);
56 pr_cont("\n");
57 }
58 }
59}
60
61void __init mminit_verify_pageflags_layout(void)
62{
63 int shift, width;
64 unsigned long or_mask, add_mask;
65
66 shift = 8 * sizeof(unsigned long);
67 width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH
68 - LAST_CPUPID_SHIFT - KASAN_TAG_WIDTH;
69 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 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 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 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 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 shift -= ZONES_WIDTH;
117 BUG_ON(shift != ZONES_PGSHIFT);
118 }
119
120 /* Check for bitmask overlaps */
121 or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
122 (NODES_MASK << NODES_PGSHIFT) |
123 (SECTIONS_MASK << SECTIONS_PGSHIFT);
124 add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
125 (NODES_MASK << NODES_PGSHIFT) +
126 (SECTIONS_MASK << SECTIONS_PGSHIFT);
127 BUG_ON(or_mask != add_mask);
128}
129
130static __init int set_mminit_loglevel(char *str)
131{
132 get_option(&str, &mminit_loglevel);
133 return 0;
134}
135early_param("mminit_loglevel", set_mminit_loglevel);
136#endif /* CONFIG_DEBUG_MEMORY_INIT */
137
138struct kobject *mm_kobj;
139EXPORT_SYMBOL_GPL(mm_kobj);
140
141#ifdef CONFIG_SMP
142s32 vm_committed_as_batch = 32;
143
144void 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
165static 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
179static struct notifier_block compute_batch_nb __meminitdata = {
180 .notifier_call = mm_compute_batch_notifier,
181 .priority = IPC_CALLBACK_PRI, /* use lowest priority */
182};
183
184static 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
196static int __init mm_sysfs_init(void)
197{
198 mm_kobj = kobject_create_and_add("mm", kernel_kobj);
199 if (!mm_kobj)
200 return -ENOMEM;
201
202 return 0;
203}
204postcore_initcall(mm_sysfs_init);