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. */ 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 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 } 127 128 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; 141 142 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 } 153 154 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 }; 171 172 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 183 184 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