Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[linux-2.6-microblaze.git] / mm / mm_init.c
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 #ifndef SECTIONS_SHIFT
23 #define SECTIONS_SHIFT  0
24 #endif
25
26 /* The zonelists are simply reported, validation is manual. */
27 void __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
65 void __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
134 static __init int set_mminit_loglevel(char *str)
135 {
136         get_option(&str, &mminit_loglevel);
137         return 0;
138 }
139 early_param("mminit_loglevel", set_mminit_loglevel);
140 #endif /* CONFIG_DEBUG_MEMORY_INIT */
141
142 struct kobject *mm_kobj;
143 EXPORT_SYMBOL_GPL(mm_kobj);
144
145 #ifdef CONFIG_SMP
146 s32 vm_committed_as_batch = 32;
147
148 void 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
169 static 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                 break;
177         default:
178                 break;
179         }
180         return NOTIFY_OK;
181 }
182
183 static struct notifier_block compute_batch_nb __meminitdata = {
184         .notifier_call = mm_compute_batch_notifier,
185         .priority = IPC_CALLBACK_PRI, /* use lowest priority */
186 };
187
188 static int __init mm_compute_batch_init(void)
189 {
190         mm_compute_batch(sysctl_overcommit_memory);
191         register_hotmemory_notifier(&compute_batch_nb);
192
193         return 0;
194 }
195
196 __initcall(mm_compute_batch_init);
197
198 #endif
199
200 static int __init mm_sysfs_init(void)
201 {
202         mm_kobj = kobject_create_and_add("mm", kernel_kobj);
203         if (!mm_kobj)
204                 return -ENOMEM;
205
206         return 0;
207 }
208 postcore_initcall(mm_sysfs_init);