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-rw-r--r--fs/ceph/crush/crush.c151
-rw-r--r--fs/ceph/crush/crush.h180
-rw-r--r--fs/ceph/crush/hash.c149
-rw-r--r--fs/ceph/crush/hash.h17
-rw-r--r--fs/ceph/crush/mapper.c609
-rw-r--r--fs/ceph/crush/mapper.h20
6 files changed, 0 insertions, 1126 deletions
diff --git a/fs/ceph/crush/crush.c b/fs/ceph/crush/crush.c
deleted file mode 100644
index fabd302e577..00000000000
--- a/fs/ceph/crush/crush.c
+++ /dev/null
@@ -1,151 +0,0 @@
1
2#ifdef __KERNEL__
3# include <linux/slab.h>
4#else
5# include <stdlib.h>
6# include <assert.h>
7# define kfree(x) do { if (x) free(x); } while (0)
8# define BUG_ON(x) assert(!(x))
9#endif
10
11#include "crush.h"
12
13const char *crush_bucket_alg_name(int alg)
14{
15 switch (alg) {
16 case CRUSH_BUCKET_UNIFORM: return "uniform";
17 case CRUSH_BUCKET_LIST: return "list";
18 case CRUSH_BUCKET_TREE: return "tree";
19 case CRUSH_BUCKET_STRAW: return "straw";
20 default: return "unknown";
21 }
22}
23
24/**
25 * crush_get_bucket_item_weight - Get weight of an item in given bucket
26 * @b: bucket pointer
27 * @p: item index in bucket
28 */
29int crush_get_bucket_item_weight(struct crush_bucket *b, int p)
30{
31 if (p >= b->size)
32 return 0;
33
34 switch (b->alg) {
35 case CRUSH_BUCKET_UNIFORM:
36 return ((struct crush_bucket_uniform *)b)->item_weight;
37 case CRUSH_BUCKET_LIST:
38 return ((struct crush_bucket_list *)b)->item_weights[p];
39 case CRUSH_BUCKET_TREE:
40 if (p & 1)
41 return ((struct crush_bucket_tree *)b)->node_weights[p];
42 return 0;
43 case CRUSH_BUCKET_STRAW:
44 return ((struct crush_bucket_straw *)b)->item_weights[p];
45 }
46 return 0;
47}
48
49/**
50 * crush_calc_parents - Calculate parent vectors for the given crush map.
51 * @map: crush_map pointer
52 */
53void crush_calc_parents(struct crush_map *map)
54{
55 int i, b, c;
56
57 for (b = 0; b < map->max_buckets; b++) {
58 if (map->buckets[b] == NULL)
59 continue;
60 for (i = 0; i < map->buckets[b]->size; i++) {
61 c = map->buckets[b]->items[i];
62 BUG_ON(c >= map->max_devices ||
63 c < -map->max_buckets);
64 if (c >= 0)
65 map->device_parents[c] = map->buckets[b]->id;
66 else
67 map->bucket_parents[-1-c] = map->buckets[b]->id;
68 }
69 }
70}
71
72void crush_destroy_bucket_uniform(struct crush_bucket_uniform *b)
73{
74 kfree(b->h.perm);
75 kfree(b->h.items);
76 kfree(b);
77}
78
79void crush_destroy_bucket_list(struct crush_bucket_list *b)
80{
81 kfree(b->item_weights);
82 kfree(b->sum_weights);
83 kfree(b->h.perm);
84 kfree(b->h.items);
85 kfree(b);
86}
87
88void crush_destroy_bucket_tree(struct crush_bucket_tree *b)
89{
90 kfree(b->node_weights);
91 kfree(b);
92}
93
94void crush_destroy_bucket_straw(struct crush_bucket_straw *b)
95{
96 kfree(b->straws);
97 kfree(b->item_weights);
98 kfree(b->h.perm);
99 kfree(b->h.items);
100 kfree(b);
101}
102
103void crush_destroy_bucket(struct crush_bucket *b)
104{
105 switch (b->alg) {
106 case CRUSH_BUCKET_UNIFORM:
107 crush_destroy_bucket_uniform((struct crush_bucket_uniform *)b);
108 break;
109 case CRUSH_BUCKET_LIST:
110 crush_destroy_bucket_list((struct crush_bucket_list *)b);
111 break;
112 case CRUSH_BUCKET_TREE:
113 crush_destroy_bucket_tree((struct crush_bucket_tree *)b);
114 break;
115 case CRUSH_BUCKET_STRAW:
116 crush_destroy_bucket_straw((struct crush_bucket_straw *)b);
117 break;
118 }
119}
120
121/**
122 * crush_destroy - Destroy a crush_map
123 * @map: crush_map pointer
124 */
125void crush_destroy(struct crush_map *map)
126{
127 int b;
128
129 /* buckets */
130 if (map->buckets) {
131 for (b = 0; b < map->max_buckets; b++) {
132 if (map->buckets[b] == NULL)
133 continue;
134 crush_destroy_bucket(map->buckets[b]);
135 }
136 kfree(map->buckets);
137 }
138
139 /* rules */
140 if (map->rules) {
141 for (b = 0; b < map->max_rules; b++)
142 kfree(map->rules[b]);
143 kfree(map->rules);
144 }
145
146 kfree(map->bucket_parents);
147 kfree(map->device_parents);
148 kfree(map);
149}
150
151
diff --git a/fs/ceph/crush/crush.h b/fs/ceph/crush/crush.h
deleted file mode 100644
index 97e435b191f..00000000000
--- a/fs/ceph/crush/crush.h
+++ /dev/null
@@ -1,180 +0,0 @@
1#ifndef CEPH_CRUSH_CRUSH_H
2#define CEPH_CRUSH_CRUSH_H
3
4#include <linux/types.h>
5
6/*
7 * CRUSH is a pseudo-random data distribution algorithm that
8 * efficiently distributes input values (typically, data objects)
9 * across a heterogeneous, structured storage cluster.
10 *
11 * The algorithm was originally described in detail in this paper
12 * (although the algorithm has evolved somewhat since then):
13 *
14 * http://www.ssrc.ucsc.edu/Papers/weil-sc06.pdf
15 *
16 * LGPL2
17 */
18
19
20#define CRUSH_MAGIC 0x00010000ul /* for detecting algorithm revisions */
21
22
23#define CRUSH_MAX_DEPTH 10 /* max crush hierarchy depth */
24#define CRUSH_MAX_SET 10 /* max size of a mapping result */
25
26
27/*
28 * CRUSH uses user-defined "rules" to describe how inputs should be
29 * mapped to devices. A rule consists of sequence of steps to perform
30 * to generate the set of output devices.
31 */
32struct crush_rule_step {
33 __u32 op;
34 __s32 arg1;
35 __s32 arg2;
36};
37
38/* step op codes */
39enum {
40 CRUSH_RULE_NOOP = 0,
41 CRUSH_RULE_TAKE = 1, /* arg1 = value to start with */
42 CRUSH_RULE_CHOOSE_FIRSTN = 2, /* arg1 = num items to pick */
43 /* arg2 = type */
44 CRUSH_RULE_CHOOSE_INDEP = 3, /* same */
45 CRUSH_RULE_EMIT = 4, /* no args */
46 CRUSH_RULE_CHOOSE_LEAF_FIRSTN = 6,
47 CRUSH_RULE_CHOOSE_LEAF_INDEP = 7,
48};
49
50/*
51 * for specifying choose num (arg1) relative to the max parameter
52 * passed to do_rule
53 */
54#define CRUSH_CHOOSE_N 0
55#define CRUSH_CHOOSE_N_MINUS(x) (-(x))
56
57/*
58 * The rule mask is used to describe what the rule is intended for.
59 * Given a ruleset and size of output set, we search through the
60 * rule list for a matching rule_mask.
61 */
62struct crush_rule_mask {
63 __u8 ruleset;
64 __u8 type;
65 __u8 min_size;
66 __u8 max_size;
67};
68
69struct crush_rule {
70 __u32 len;
71 struct crush_rule_mask mask;
72 struct crush_rule_step steps[0];
73};
74
75#define crush_rule_size(len) (sizeof(struct crush_rule) + \
76 (len)*sizeof(struct crush_rule_step))
77
78
79
80/*
81 * A bucket is a named container of other items (either devices or
82 * other buckets). Items within a bucket are chosen using one of a
83 * few different algorithms. The table summarizes how the speed of
84 * each option measures up against mapping stability when items are
85 * added or removed.
86 *
87 * Bucket Alg Speed Additions Removals
88 * ------------------------------------------------
89 * uniform O(1) poor poor
90 * list O(n) optimal poor
91 * tree O(log n) good good
92 * straw O(n) optimal optimal
93 */
94enum {
95 CRUSH_BUCKET_UNIFORM = 1,
96 CRUSH_BUCKET_LIST = 2,
97 CRUSH_BUCKET_TREE = 3,
98 CRUSH_BUCKET_STRAW = 4
99};
100extern const char *crush_bucket_alg_name(int alg);
101
102struct crush_bucket {
103 __s32 id; /* this'll be negative */
104 __u16 type; /* non-zero; type=0 is reserved for devices */
105 __u8 alg; /* one of CRUSH_BUCKET_* */
106 __u8 hash; /* which hash function to use, CRUSH_HASH_* */
107 __u32 weight; /* 16-bit fixed point */
108 __u32 size; /* num items */
109 __s32 *items;
110
111 /*
112 * cached random permutation: used for uniform bucket and for
113 * the linear search fallback for the other bucket types.
114 */
115 __u32 perm_x; /* @x for which *perm is defined */
116 __u32 perm_n; /* num elements of *perm that are permuted/defined */
117 __u32 *perm;
118};
119
120struct crush_bucket_uniform {
121 struct crush_bucket h;
122 __u32 item_weight; /* 16-bit fixed point; all items equally weighted */
123};
124
125struct crush_bucket_list {
126 struct crush_bucket h;
127 __u32 *item_weights; /* 16-bit fixed point */
128 __u32 *sum_weights; /* 16-bit fixed point. element i is sum
129 of weights 0..i, inclusive */
130};
131
132struct crush_bucket_tree {
133 struct crush_bucket h; /* note: h.size is _tree_ size, not number of
134 actual items */
135 __u8 num_nodes;
136 __u32 *node_weights;
137};
138
139struct crush_bucket_straw {
140 struct crush_bucket h;
141 __u32 *item_weights; /* 16-bit fixed point */
142 __u32 *straws; /* 16-bit fixed point */
143};
144
145
146
147/*
148 * CRUSH map includes all buckets, rules, etc.
149 */
150struct crush_map {
151 struct crush_bucket **buckets;
152 struct crush_rule **rules;
153
154 /*
155 * Parent pointers to identify the parent bucket a device or
156 * bucket in the hierarchy. If an item appears more than
157 * once, this is the _last_ time it appeared (where buckets
158 * are processed in bucket id order, from -1 on down to
159 * -max_buckets.
160 */
161 __u32 *bucket_parents;
162 __u32 *device_parents;
163
164 __s32 max_buckets;
165 __u32 max_rules;
166 __s32 max_devices;
167};
168
169
170/* crush.c */
171extern int crush_get_bucket_item_weight(struct crush_bucket *b, int pos);
172extern void crush_calc_parents(struct crush_map *map);
173extern void crush_destroy_bucket_uniform(struct crush_bucket_uniform *b);
174extern void crush_destroy_bucket_list(struct crush_bucket_list *b);
175extern void crush_destroy_bucket_tree(struct crush_bucket_tree *b);
176extern void crush_destroy_bucket_straw(struct crush_bucket_straw *b);
177extern void crush_destroy_bucket(struct crush_bucket *b);
178extern void crush_destroy(struct crush_map *map);
179
180#endif
diff --git a/fs/ceph/crush/hash.c b/fs/ceph/crush/hash.c
deleted file mode 100644
index 5873aed694b..00000000000
--- a/fs/ceph/crush/hash.c
+++ /dev/null
@@ -1,149 +0,0 @@
1
2#include <linux/types.h>
3#include "hash.h"
4
5/*
6 * Robert Jenkins' function for mixing 32-bit values
7 * http://burtleburtle.net/bob/hash/evahash.html
8 * a, b = random bits, c = input and output
9 */
10#define crush_hashmix(a, b, c) do { \
11 a = a-b; a = a-c; a = a^(c>>13); \
12 b = b-c; b = b-a; b = b^(a<<8); \
13 c = c-a; c = c-b; c = c^(b>>13); \
14 a = a-b; a = a-c; a = a^(c>>12); \
15 b = b-c; b = b-a; b = b^(a<<16); \
16 c = c-a; c = c-b; c = c^(b>>5); \
17 a = a-b; a = a-c; a = a^(c>>3); \
18 b = b-c; b = b-a; b = b^(a<<10); \
19 c = c-a; c = c-b; c = c^(b>>15); \
20 } while (0)
21
22#define crush_hash_seed 1315423911
23
24static __u32 crush_hash32_rjenkins1(__u32 a)
25{
26 __u32 hash = crush_hash_seed ^ a;
27 __u32 b = a;
28 __u32 x = 231232;
29 __u32 y = 1232;
30 crush_hashmix(b, x, hash);
31 crush_hashmix(y, a, hash);
32 return hash;
33}
34
35static __u32 crush_hash32_rjenkins1_2(__u32 a, __u32 b)
36{
37 __u32 hash = crush_hash_seed ^ a ^ b;
38 __u32 x = 231232;
39 __u32 y = 1232;
40 crush_hashmix(a, b, hash);
41 crush_hashmix(x, a, hash);
42 crush_hashmix(b, y, hash);
43 return hash;
44}
45
46static __u32 crush_hash32_rjenkins1_3(__u32 a, __u32 b, __u32 c)
47{
48 __u32 hash = crush_hash_seed ^ a ^ b ^ c;
49 __u32 x = 231232;
50 __u32 y = 1232;
51 crush_hashmix(a, b, hash);
52 crush_hashmix(c, x, hash);
53 crush_hashmix(y, a, hash);
54 crush_hashmix(b, x, hash);
55 crush_hashmix(y, c, hash);
56 return hash;
57}
58
59static __u32 crush_hash32_rjenkins1_4(__u32 a, __u32 b, __u32 c, __u32 d)
60{
61 __u32 hash = crush_hash_seed ^ a ^ b ^ c ^ d;
62 __u32 x = 231232;
63 __u32 y = 1232;
64 crush_hashmix(a, b, hash);
65 crush_hashmix(c, d, hash);
66 crush_hashmix(a, x, hash);
67 crush_hashmix(y, b, hash);
68 crush_hashmix(c, x, hash);
69 crush_hashmix(y, d, hash);
70 return hash;
71}
72
73static __u32 crush_hash32_rjenkins1_5(__u32 a, __u32 b, __u32 c, __u32 d,
74 __u32 e)
75{
76 __u32 hash = crush_hash_seed ^ a ^ b ^ c ^ d ^ e;
77 __u32 x = 231232;
78 __u32 y = 1232;
79 crush_hashmix(a, b, hash);
80 crush_hashmix(c, d, hash);
81 crush_hashmix(e, x, hash);
82 crush_hashmix(y, a, hash);
83 crush_hashmix(b, x, hash);
84 crush_hashmix(y, c, hash);
85 crush_hashmix(d, x, hash);
86 crush_hashmix(y, e, hash);
87 return hash;
88}
89
90
91__u32 crush_hash32(int type, __u32 a)
92{
93 switch (type) {
94 case CRUSH_HASH_RJENKINS1:
95 return crush_hash32_rjenkins1(a);
96 default:
97 return 0;
98 }
99}
100
101__u32 crush_hash32_2(int type, __u32 a, __u32 b)
102{
103 switch (type) {
104 case CRUSH_HASH_RJENKINS1:
105 return crush_hash32_rjenkins1_2(a, b);
106 default:
107 return 0;
108 }
109}
110
111__u32 crush_hash32_3(int type, __u32 a, __u32 b, __u32 c)
112{
113 switch (type) {
114 case CRUSH_HASH_RJENKINS1:
115 return crush_hash32_rjenkins1_3(a, b, c);
116 default:
117 return 0;
118 }
119}
120
121__u32 crush_hash32_4(int type, __u32 a, __u32 b, __u32 c, __u32 d)
122{
123 switch (type) {
124 case CRUSH_HASH_RJENKINS1:
125 return crush_hash32_rjenkins1_4(a, b, c, d);
126 default:
127 return 0;
128 }
129}
130
131__u32 crush_hash32_5(int type, __u32 a, __u32 b, __u32 c, __u32 d, __u32 e)
132{
133 switch (type) {
134 case CRUSH_HASH_RJENKINS1:
135 return crush_hash32_rjenkins1_5(a, b, c, d, e);
136 default:
137 return 0;
138 }
139}
140
141const char *crush_hash_name(int type)
142{
143 switch (type) {
144 case CRUSH_HASH_RJENKINS1:
145 return "rjenkins1";
146 default:
147 return "unknown";
148 }
149}
diff --git a/fs/ceph/crush/hash.h b/fs/ceph/crush/hash.h
deleted file mode 100644
index 91e884230d5..00000000000
--- a/fs/ceph/crush/hash.h
+++ /dev/null
@@ -1,17 +0,0 @@
1#ifndef CEPH_CRUSH_HASH_H
2#define CEPH_CRUSH_HASH_H
3
4#define CRUSH_HASH_RJENKINS1 0
5
6#define CRUSH_HASH_DEFAULT CRUSH_HASH_RJENKINS1
7
8extern const char *crush_hash_name(int type);
9
10extern __u32 crush_hash32(int type, __u32 a);
11extern __u32 crush_hash32_2(int type, __u32 a, __u32 b);
12extern __u32 crush_hash32_3(int type, __u32 a, __u32 b, __u32 c);
13extern __u32 crush_hash32_4(int type, __u32 a, __u32 b, __u32 c, __u32 d);
14extern __u32 crush_hash32_5(int type, __u32 a, __u32 b, __u32 c, __u32 d,
15 __u32 e);
16
17#endif
diff --git a/fs/ceph/crush/mapper.c b/fs/ceph/crush/mapper.c
deleted file mode 100644
index a4eec133258..00000000000
--- a/fs/ceph/crush/mapper.c
+++ /dev/null
@@ -1,609 +0,0 @@
1
2#ifdef __KERNEL__
3# include <linux/string.h>
4# include <linux/slab.h>
5# include <linux/bug.h>
6# include <linux/kernel.h>
7# ifndef dprintk
8# define dprintk(args...)
9# endif
10#else
11# include <string.h>
12# include <stdio.h>
13# include <stdlib.h>
14# include <assert.h>
15# define BUG_ON(x) assert(!(x))
16# define dprintk(args...) /* printf(args) */
17# define kmalloc(x, f) malloc(x)
18# define kfree(x) free(x)
19#endif
20
21#include "crush.h"
22#include "hash.h"
23
24/*
25 * Implement the core CRUSH mapping algorithm.
26 */
27
28/**
29 * crush_find_rule - find a crush_rule id for a given ruleset, type, and size.
30 * @map: the crush_map
31 * @ruleset: the storage ruleset id (user defined)
32 * @type: storage ruleset type (user defined)
33 * @size: output set size
34 */
35int crush_find_rule(struct crush_map *map, int ruleset, int type, int size)
36{
37 int i;
38
39 for (i = 0; i < map->max_rules; i++) {
40 if (map->rules[i] &&
41 map->rules[i]->mask.ruleset == ruleset &&
42 map->rules[i]->mask.type == type &&
43 map->rules[i]->mask.min_size <= size &&
44 map->rules[i]->mask.max_size >= size)
45 return i;
46 }
47 return -1;
48}
49
50
51/*
52 * bucket choose methods
53 *
54 * For each bucket algorithm, we have a "choose" method that, given a
55 * crush input @x and replica position (usually, position in output set) @r,
56 * will produce an item in the bucket.
57 */
58
59/*
60 * Choose based on a random permutation of the bucket.
61 *
62 * We used to use some prime number arithmetic to do this, but it
63 * wasn't very random, and had some other bad behaviors. Instead, we
64 * calculate an actual random permutation of the bucket members.
65 * Since this is expensive, we optimize for the r=0 case, which
66 * captures the vast majority of calls.
67 */
68static int bucket_perm_choose(struct crush_bucket *bucket,
69 int x, int r)
70{
71 unsigned pr = r % bucket->size;
72 unsigned i, s;
73
74 /* start a new permutation if @x has changed */
75 if (bucket->perm_x != x || bucket->perm_n == 0) {
76 dprintk("bucket %d new x=%d\n", bucket->id, x);
77 bucket->perm_x = x;
78
79 /* optimize common r=0 case */
80 if (pr == 0) {
81 s = crush_hash32_3(bucket->hash, x, bucket->id, 0) %
82 bucket->size;
83 bucket->perm[0] = s;
84 bucket->perm_n = 0xffff; /* magic value, see below */
85 goto out;
86 }
87
88 for (i = 0; i < bucket->size; i++)
89 bucket->perm[i] = i;
90 bucket->perm_n = 0;
91 } else if (bucket->perm_n == 0xffff) {
92 /* clean up after the r=0 case above */
93 for (i = 1; i < bucket->size; i++)
94 bucket->perm[i] = i;
95 bucket->perm[bucket->perm[0]] = 0;
96 bucket->perm_n = 1;
97 }
98
99 /* calculate permutation up to pr */
100 for (i = 0; i < bucket->perm_n; i++)
101 dprintk(" perm_choose have %d: %d\n", i, bucket->perm[i]);
102 while (bucket->perm_n <= pr) {
103 unsigned p = bucket->perm_n;
104 /* no point in swapping the final entry */
105 if (p < bucket->size - 1) {
106 i = crush_hash32_3(bucket->hash, x, bucket->id, p) %
107 (bucket->size - p);
108 if (i) {
109 unsigned t = bucket->perm[p + i];
110 bucket->perm[p + i] = bucket->perm[p];
111 bucket->perm[p] = t;
112 }
113 dprintk(" perm_choose swap %d with %d\n", p, p+i);
114 }
115 bucket->perm_n++;
116 }
117 for (i = 0; i < bucket->size; i++)
118 dprintk(" perm_choose %d: %d\n", i, bucket->perm[i]);
119
120 s = bucket->perm[pr];
121out:
122 dprintk(" perm_choose %d sz=%d x=%d r=%d (%d) s=%d\n", bucket->id,
123 bucket->size, x, r, pr, s);
124 return bucket->items[s];
125}
126
127/* uniform */
128static int bucket_uniform_choose(struct crush_bucket_uniform *bucket,
129 int x, int r)
130{
131 return bucket_perm_choose(&bucket->h, x, r);
132}
133
134/* list */
135static int bucket_list_choose(struct crush_bucket_list *bucket,
136 int x, int r)
137{
138 int i;
139
140 for (i = bucket->h.size-1; i >= 0; i--) {
141 __u64 w = crush_hash32_4(bucket->h.hash,x, bucket->h.items[i],
142 r, bucket->h.id);
143 w &= 0xffff;
144 dprintk("list_choose i=%d x=%d r=%d item %d weight %x "
145 "sw %x rand %llx",
146 i, x, r, bucket->h.items[i], bucket->item_weights[i],
147 bucket->sum_weights[i], w);
148 w *= bucket->sum_weights[i];
149 w = w >> 16;
150 /*dprintk(" scaled %llx\n", w);*/
151 if (w < bucket->item_weights[i])
152 return bucket->h.items[i];
153 }
154
155 BUG_ON(1);
156 return 0;
157}
158
159
160/* (binary) tree */
161static int height(int n)
162{
163 int h = 0;
164 while ((n & 1) == 0) {
165 h++;
166 n = n >> 1;
167 }
168 return h;
169}
170
171static int left(int x)
172{
173 int h = height(x);
174 return x - (1 << (h-1));
175}
176
177static int right(int x)
178{
179 int h = height(x);
180 return x + (1 << (h-1));
181}
182
183static int terminal(int x)
184{
185 return x & 1;
186}
187
188static int bucket_tree_choose(struct crush_bucket_tree *bucket,
189 int x, int r)
190{
191 int n, l;
192 __u32 w;
193 __u64 t;
194
195 /* start at root */
196 n = bucket->num_nodes >> 1;
197
198 while (!terminal(n)) {
199 /* pick point in [0, w) */
200 w = bucket->node_weights[n];
201 t = (__u64)crush_hash32_4(bucket->h.hash, x, n, r,
202 bucket->h.id) * (__u64)w;
203 t = t >> 32;
204
205 /* descend to the left or right? */
206 l = left(n);
207 if (t < bucket->node_weights[l])
208 n = l;
209 else
210 n = right(n);
211 }
212
213 return bucket->h.items[n >> 1];
214}
215
216
217/* straw */
218
219static int bucket_straw_choose(struct crush_bucket_straw *bucket,
220 int x, int r)
221{
222 int i;
223 int high = 0;
224 __u64 high_draw = 0;
225 __u64 draw;
226
227 for (i = 0; i < bucket->h.size; i++) {
228 draw = crush_hash32_3(bucket->h.hash, x, bucket->h.items[i], r);
229 draw &= 0xffff;
230 draw *= bucket->straws[i];
231 if (i == 0 || draw > high_draw) {
232 high = i;
233 high_draw = draw;
234 }
235 }
236 return bucket->h.items[high];
237}
238
239static int crush_bucket_choose(struct crush_bucket *in, int x, int r)
240{
241 dprintk(" crush_bucket_choose %d x=%d r=%d\n", in->id, x, r);
242 switch (in->alg) {
243 case CRUSH_BUCKET_UNIFORM:
244 return bucket_uniform_choose((struct crush_bucket_uniform *)in,
245 x, r);
246 case CRUSH_BUCKET_LIST:
247 return bucket_list_choose((struct crush_bucket_list *)in,
248 x, r);
249 case CRUSH_BUCKET_TREE:
250 return bucket_tree_choose((struct crush_bucket_tree *)in,
251 x, r);
252 case CRUSH_BUCKET_STRAW:
253 return bucket_straw_choose((struct crush_bucket_straw *)in,
254 x, r);
255 default:
256 BUG_ON(1);
257 return in->items[0];
258 }
259}
260
261/*
262 * true if device is marked "out" (failed, fully offloaded)
263 * of the cluster
264 */
265static int is_out(struct crush_map *map, __u32 *weight, int item, int x)
266{
267 if (weight[item] >= 0x10000)
268 return 0;
269 if (weight[item] == 0)
270 return 1;
271 if ((crush_hash32_2(CRUSH_HASH_RJENKINS1, x, item) & 0xffff)
272 < weight[item])
273 return 0;
274 return 1;
275}
276
277/**
278 * crush_choose - choose numrep distinct items of given type
279 * @map: the crush_map
280 * @bucket: the bucket we are choose an item from
281 * @x: crush input value
282 * @numrep: the number of items to choose
283 * @type: the type of item to choose
284 * @out: pointer to output vector
285 * @outpos: our position in that vector
286 * @firstn: true if choosing "first n" items, false if choosing "indep"
287 * @recurse_to_leaf: true if we want one device under each item of given type
288 * @out2: second output vector for leaf items (if @recurse_to_leaf)
289 */
290static int crush_choose(struct crush_map *map,
291 struct crush_bucket *bucket,
292 __u32 *weight,
293 int x, int numrep, int type,
294 int *out, int outpos,
295 int firstn, int recurse_to_leaf,
296 int *out2)
297{
298 int rep;
299 int ftotal, flocal;
300 int retry_descent, retry_bucket, skip_rep;
301 struct crush_bucket *in = bucket;
302 int r;
303 int i;
304 int item = 0;
305 int itemtype;
306 int collide, reject;
307 const int orig_tries = 5; /* attempts before we fall back to search */
308
309 dprintk("CHOOSE%s bucket %d x %d outpos %d numrep %d\n", recurse_to_leaf ? "_LEAF" : "",
310 bucket->id, x, outpos, numrep);
311
312 for (rep = outpos; rep < numrep; rep++) {
313 /* keep trying until we get a non-out, non-colliding item */
314 ftotal = 0;
315 skip_rep = 0;
316 do {
317 retry_descent = 0;
318 in = bucket; /* initial bucket */
319
320 /* choose through intervening buckets */
321 flocal = 0;
322 do {
323 collide = 0;
324 retry_bucket = 0;
325 r = rep;
326 if (in->alg == CRUSH_BUCKET_UNIFORM) {
327 /* be careful */
328 if (firstn || numrep >= in->size)
329 /* r' = r + f_total */
330 r += ftotal;
331 else if (in->size % numrep == 0)
332 /* r'=r+(n+1)*f_local */
333 r += (numrep+1) *
334 (flocal+ftotal);
335 else
336 /* r' = r + n*f_local */
337 r += numrep * (flocal+ftotal);
338 } else {
339 if (firstn)
340 /* r' = r + f_total */
341 r += ftotal;
342 else
343 /* r' = r + n*f_local */
344 r += numrep * (flocal+ftotal);
345 }
346
347 /* bucket choose */
348 if (in->size == 0) {
349 reject = 1;
350 goto reject;
351 }
352 if (flocal >= (in->size>>1) &&
353 flocal > orig_tries)
354 item = bucket_perm_choose(in, x, r);
355 else
356 item = crush_bucket_choose(in, x, r);
357 BUG_ON(item >= map->max_devices);
358
359 /* desired type? */
360 if (item < 0)
361 itemtype = map->buckets[-1-item]->type;
362 else
363 itemtype = 0;
364 dprintk(" item %d type %d\n", item, itemtype);
365
366 /* keep going? */
367 if (itemtype != type) {
368 BUG_ON(item >= 0 ||
369 (-1-item) >= map->max_buckets);
370 in = map->buckets[-1-item];
371 retry_bucket = 1;
372 continue;
373 }
374
375 /* collision? */
376 for (i = 0; i < outpos; i++) {
377 if (out[i] == item) {
378 collide = 1;
379 break;
380 }
381 }
382
383 reject = 0;
384 if (recurse_to_leaf) {
385 if (item < 0) {
386 if (crush_choose(map,
387 map->buckets[-1-item],
388 weight,
389 x, outpos+1, 0,
390 out2, outpos,
391 firstn, 0,
392 NULL) <= outpos)
393 /* didn't get leaf */
394 reject = 1;
395 } else {
396 /* we already have a leaf! */
397 out2[outpos] = item;
398 }
399 }
400
401 if (!reject) {
402 /* out? */
403 if (itemtype == 0)
404 reject = is_out(map, weight,
405 item, x);
406 else
407 reject = 0;
408 }
409
410reject:
411 if (reject || collide) {
412 ftotal++;
413 flocal++;
414
415 if (collide && flocal < 3)
416 /* retry locally a few times */
417 retry_bucket = 1;
418 else if (flocal < in->size + orig_tries)
419 /* exhaustive bucket search */
420 retry_bucket = 1;
421 else if (ftotal < 20)
422 /* then retry descent */
423 retry_descent = 1;
424 else
425 /* else give up */
426 skip_rep = 1;
427 dprintk(" reject %d collide %d "
428 "ftotal %d flocal %d\n",
429 reject, collide, ftotal,
430 flocal);
431 }
432 } while (retry_bucket);
433 } while (retry_descent);
434
435 if (skip_rep) {
436 dprintk("skip rep\n");
437 continue;
438 }
439
440 dprintk("CHOOSE got %d\n", item);
441 out[outpos] = item;
442 outpos++;
443 }
444
445 dprintk("CHOOSE returns %d\n", outpos);
446 return outpos;
447}
448
449
450/**
451 * crush_do_rule - calculate a mapping with the given input and rule
452 * @map: the crush_map
453 * @ruleno: the rule id
454 * @x: hash input
455 * @result: pointer to result vector
456 * @result_max: maximum result size
457 * @force: force initial replica choice; -1 for none
458 */
459int crush_do_rule(struct crush_map *map,
460 int ruleno, int x, int *result, int result_max,
461 int force, __u32 *weight)
462{
463 int result_len;
464 int force_context[CRUSH_MAX_DEPTH];
465 int force_pos = -1;
466 int a[CRUSH_MAX_SET];
467 int b[CRUSH_MAX_SET];
468 int c[CRUSH_MAX_SET];
469 int recurse_to_leaf;
470 int *w;
471 int wsize = 0;
472 int *o;
473 int osize;
474 int *tmp;
475 struct crush_rule *rule;
476 int step;
477 int i, j;
478 int numrep;
479 int firstn;
480 int rc = -1;
481
482 BUG_ON(ruleno >= map->max_rules);
483
484 rule = map->rules[ruleno];
485 result_len = 0;
486 w = a;
487 o = b;
488
489 /*
490 * determine hierarchical context of force, if any. note
491 * that this may or may not correspond to the specific types
492 * referenced by the crush rule.
493 */
494 if (force >= 0) {
495 if (force >= map->max_devices ||
496 map->device_parents[force] == 0) {
497 /*dprintk("CRUSH: forcefed device dne\n");*/
498 rc = -1; /* force fed device dne */
499 goto out;
500 }
501 if (!is_out(map, weight, force, x)) {
502 while (1) {
503 force_context[++force_pos] = force;
504 if (force >= 0)
505 force = map->device_parents[force];
506 else
507 force = map->bucket_parents[-1-force];
508 if (force == 0)
509 break;
510 }
511 }
512 }
513
514 for (step = 0; step < rule->len; step++) {
515 firstn = 0;
516 switch (rule->steps[step].op) {
517 case CRUSH_RULE_TAKE:
518 w[0] = rule->steps[step].arg1;
519 if (force_pos >= 0) {
520 BUG_ON(force_context[force_pos] != w[0]);
521 force_pos--;
522 }
523 wsize = 1;
524 break;
525
526 case CRUSH_RULE_CHOOSE_LEAF_FIRSTN:
527 case CRUSH_RULE_CHOOSE_FIRSTN:
528 firstn = 1;
529 case CRUSH_RULE_CHOOSE_LEAF_INDEP:
530 case CRUSH_RULE_CHOOSE_INDEP:
531 BUG_ON(wsize == 0);
532
533 recurse_to_leaf =
534 rule->steps[step].op ==
535 CRUSH_RULE_CHOOSE_LEAF_FIRSTN ||
536 rule->steps[step].op ==
537 CRUSH_RULE_CHOOSE_LEAF_INDEP;
538
539 /* reset output */
540 osize = 0;
541
542 for (i = 0; i < wsize; i++) {
543 /*
544 * see CRUSH_N, CRUSH_N_MINUS macros.
545 * basically, numrep <= 0 means relative to
546 * the provided result_max
547 */
548 numrep = rule->steps[step].arg1;
549 if (numrep <= 0) {
550 numrep += result_max;
551 if (numrep <= 0)
552 continue;
553 }
554 j = 0;
555 if (osize == 0 && force_pos >= 0) {
556 /* skip any intermediate types */
557 while (force_pos &&
558 force_context[force_pos] < 0 &&
559 rule->steps[step].arg2 !=
560 map->buckets[-1 -
561 force_context[force_pos]]->type)
562 force_pos--;
563 o[osize] = force_context[force_pos];
564 if (recurse_to_leaf)
565 c[osize] = force_context[0];
566 j++;
567 force_pos--;
568 }
569 osize += crush_choose(map,
570 map->buckets[-1-w[i]],
571 weight,
572 x, numrep,
573 rule->steps[step].arg2,
574 o+osize, j,
575 firstn,
576 recurse_to_leaf, c+osize);
577 }
578
579 if (recurse_to_leaf)
580 /* copy final _leaf_ values to output set */
581 memcpy(o, c, osize*sizeof(*o));
582
583 /* swap t and w arrays */
584 tmp = o;
585 o = w;
586 w = tmp;
587 wsize = osize;
588 break;
589
590
591 case CRUSH_RULE_EMIT:
592 for (i = 0; i < wsize && result_len < result_max; i++) {
593 result[result_len] = w[i];
594 result_len++;
595 }
596 wsize = 0;
597 break;
598
599 default:
600 BUG_ON(1);
601 }
602 }
603 rc = result_len;
604
605out:
606 return rc;
607}
608
609
diff --git a/fs/ceph/crush/mapper.h b/fs/ceph/crush/mapper.h
deleted file mode 100644
index c46b99c18bb..00000000000
--- a/fs/ceph/crush/mapper.h
+++ /dev/null
@@ -1,20 +0,0 @@
1#ifndef CEPH_CRUSH_MAPPER_H
2#define CEPH_CRUSH_MAPPER_H
3
4/*
5 * CRUSH functions for find rules and then mapping an input to an
6 * output set.
7 *
8 * LGPL2
9 */
10
11#include "crush.h"
12
13extern int crush_find_rule(struct crush_map *map, int pool, int type, int size);
14extern int crush_do_rule(struct crush_map *map,
15 int ruleno,
16 int x, int *result, int result_max,
17 int forcefeed, /* -1 for none */
18 __u32 *weights);
19
20#endif
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-18 22:13:55 -0500