xref: /openbmc/linux/tools/perf/util/mem2node.c (revision e021ae7f)
1 #include <errno.h>
2 #include <inttypes.h>
3 #include <asm/bug.h>
4 #include <linux/bitmap.h>
5 #include <linux/kernel.h>
6 #include <linux/zalloc.h>
7 #include "debug.h"
8 #include "env.h"
9 #include "mem2node.h"
10 
11 struct phys_entry {
12 	struct rb_node	rb_node;
13 	u64	start;
14 	u64	end;
15 	u64	node;
16 };
17 
18 static void phys_entry__insert(struct phys_entry *entry, struct rb_root *root)
19 {
20 	struct rb_node **p = &root->rb_node;
21 	struct rb_node *parent = NULL;
22 	struct phys_entry *e;
23 
24 	while (*p != NULL) {
25 		parent = *p;
26 		e = rb_entry(parent, struct phys_entry, rb_node);
27 
28 		if (entry->start < e->start)
29 			p = &(*p)->rb_left;
30 		else
31 			p = &(*p)->rb_right;
32 	}
33 
34 	rb_link_node(&entry->rb_node, parent, p);
35 	rb_insert_color(&entry->rb_node, root);
36 }
37 
38 static void
39 phys_entry__init(struct phys_entry *entry, u64 start, u64 bsize, u64 node)
40 {
41 	entry->start = start;
42 	entry->end   = start + bsize;
43 	entry->node  = node;
44 	RB_CLEAR_NODE(&entry->rb_node);
45 }
46 
47 int mem2node__init(struct mem2node *map, struct perf_env *env)
48 {
49 	struct memory_node *n, *nodes = &env->memory_nodes[0];
50 	struct phys_entry *entries, *tmp_entries;
51 	u64 bsize = env->memory_bsize;
52 	int i, j = 0, max = 0;
53 
54 	memset(map, 0x0, sizeof(*map));
55 	map->root = RB_ROOT;
56 
57 	for (i = 0; i < env->nr_memory_nodes; i++) {
58 		n = &nodes[i];
59 		max += bitmap_weight(n->set, n->size);
60 	}
61 
62 	entries = zalloc(sizeof(*entries) * max);
63 	if (!entries)
64 		return -ENOMEM;
65 
66 	for (i = 0; i < env->nr_memory_nodes; i++) {
67 		u64 bit;
68 
69 		n = &nodes[i];
70 
71 		for (bit = 0; bit < n->size; bit++) {
72 			u64 start;
73 
74 			if (!test_bit(bit, n->set))
75 				continue;
76 
77 			start = bit * bsize;
78 
79 			/*
80 			 * Merge nearby areas, we walk in order
81 			 * through the bitmap, so no need to sort.
82 			 */
83 			if (j > 0) {
84 				struct phys_entry *prev = &entries[j - 1];
85 
86 				if ((prev->end == start) &&
87 				    (prev->node == n->node)) {
88 					prev->end += bsize;
89 					continue;
90 				}
91 			}
92 
93 			phys_entry__init(&entries[j++], start, bsize, n->node);
94 		}
95 	}
96 
97 	/* Cut unused entries, due to merging. */
98 	tmp_entries = realloc(entries, sizeof(*entries) * j);
99 	if (tmp_entries ||
100 	    WARN_ONCE(j == 0, "No memory nodes, is CONFIG_MEMORY_HOTPLUG enabled?\n"))
101 		entries = tmp_entries;
102 
103 	for (i = 0; i < j; i++) {
104 		pr_debug("mem2node %03" PRIu64 " [0x%016" PRIx64 "-0x%016" PRIx64 "]\n",
105 			 entries[i].node, entries[i].start, entries[i].end);
106 
107 		phys_entry__insert(&entries[i], &map->root);
108 	}
109 
110 	map->entries = entries;
111 	return 0;
112 }
113 
114 void mem2node__exit(struct mem2node *map)
115 {
116 	zfree(&map->entries);
117 }
118 
119 int mem2node__node(struct mem2node *map, u64 addr)
120 {
121 	struct rb_node **p, *parent = NULL;
122 	struct phys_entry *entry;
123 
124 	p = &map->root.rb_node;
125 	while (*p != NULL) {
126 		parent = *p;
127 		entry = rb_entry(parent, struct phys_entry, rb_node);
128 		if (addr < entry->start)
129 			p = &(*p)->rb_left;
130 		else if (addr >= entry->end)
131 			p = &(*p)->rb_right;
132 		else
133 			goto out;
134 	}
135 
136 	entry = NULL;
137 out:
138 	return entry ? (int) entry->node : -1;
139 }
140