Reflects ceph.git commit 86e978036a4ecbac4c875e7c00f6c5bbe37282d3.
Signed-off-by: Ilya Dryomov <ilya.dryomov@xxxxxxxxxxx>
---
include/linux/crush/crush.h | 3 +-
net/ceph/crush/mapper.c | 172 ++++++++++++++++++++++++++++++++++++++++---
2 files changed, 165 insertions(+), 10 deletions(-)
diff --git a/include/linux/crush/crush.h b/include/linux/crush/crush.h
index 3d6a12928560..4023b1b52296 100644
--- a/include/linux/crush/crush.h
+++ b/include/linux/crush/crush.h
@@ -22,7 +22,8 @@
#define CRUSH_MAX_DEPTH 10 /* max crush hierarchy depth */
-#define CRUSH_ITEM_UNDEF 0x7fffffff /* undefined result */
+#define CRUSH_ITEM_UNDEF 0x7ffffffe /* undefined result (internal use only) */
+#define CRUSH_ITEM_NONE 0x7fffffff /* no result */
/*
* CRUSH uses user-defined "rules" to describe how inputs should be
diff --git a/net/ceph/crush/mapper.c b/net/ceph/crush/mapper.c
index a8605245d190..caeb1066bea3 100644
--- a/net/ceph/crush/mapper.c
+++ b/net/ceph/crush/mapper.c
@@ -474,6 +474,148 @@ reject:
/**
+ * choose indep: alternative breadth-first positionally stable mapping
+ *
+ */
+static void crush_choose_indep(const struct crush_map *map,
+ struct crush_bucket *bucket,
+ const __u32 *weight, int weight_max,
+ int x, int numrep, int type,
+ int *out, int outpos,
+ int recurse_to_leaf,
+ int *out2)
+{
+ struct crush_bucket *in = bucket;
+ int left = numrep - outpos;
+ int rep;
+ unsigned int ftotal;
+ int r;
+ int i;
+ int item = 0;
+ int itemtype;
+ int collide;
+
+ dprintk("CHOOSE%s INDEP bucket %d x %d outpos %d numrep %d\n", recurse_to_leaf ? "_LEAF" : "",
+ bucket->id, x, outpos, numrep);
+
+ /* initially my result is undefined */
+ for (rep = outpos; rep < numrep; rep++) {
+ out[rep] = CRUSH_ITEM_UNDEF;
+ if (out2)
+ out2[rep] = CRUSH_ITEM_UNDEF;
+ }
+
+ for (ftotal = 0; left > 0 && ftotal < map->choose_total_tries; ftotal++) {
+ for (rep = outpos; rep < numrep; rep++) {
+ if (out[rep] != CRUSH_ITEM_UNDEF)
+ continue;
+
+ in = bucket; /* initial bucket */
+
+ /* choose through intervening buckets */
+ for (;;) {
+ r = rep;
+
+ /* be careful */
+ if (in->alg == CRUSH_BUCKET_UNIFORM &&
+ in->size % numrep == 0)
+ /* r'=r+(n+1)*f_total */
+ r += (numrep+1) * ftotal;
+ else
+ /* r' = r + n*f_total */
+ r += numrep * ftotal;
+
+ /* bucket choose */
+ if (in->size == 0) {
+ dprintk(" empty bucket\n");
+ break;
+ }
+
+ item = crush_bucket_choose(in, x, r);
+ if (item >= map->max_devices) {
+ dprintk(" bad item %d\n", item);
+ out[rep] = CRUSH_ITEM_NONE;
+ if (out2)
+ out2[rep] = CRUSH_ITEM_NONE;
+ left--;
+ break;
+ }
+
+ /* desired type? */
+ if (item < 0)
+ itemtype = map->buckets[-1-item]->type;
+ else
+ itemtype = 0;
+ dprintk(" item %d type %d\n", item, itemtype);
+
+ /* keep going? */
+ if (itemtype != type) {
+ if (item >= 0 ||
+ (-1-item) >= map->max_buckets) {
+ dprintk(" bad item type %d\n", type);
+ out[rep] = CRUSH_ITEM_NONE;
+ if (out2)
+ out2[rep] =
+ CRUSH_ITEM_NONE;
+ left--;
+ break;
+ }
+ in = map->buckets[-1-item];
+ continue;
+ }
+
+ /* collision? */
+ collide = 0;
+ for (i = outpos; i < numrep; i++) {
+ if (out[i] == item) {
+ collide = 1;
+ break;
+ }
+ }
+ if (collide)
+ break;
+
+ if (recurse_to_leaf) {
+ if (item < 0) {
+ crush_choose_indep(map,
+ map->buckets[-1-item],
+ weight, weight_max,
+ x, rep+1, 0,
+ out2, rep,
+ 0, NULL);
+ if (out2[rep] == CRUSH_ITEM_NONE) {
+ /* placed nothing; no leaf */
+ break;
+ }
+ } else {
+ /* we already have a leaf! */
+ out2[rep] = item;
+ }
+ }
+
+ /* out? */
+ if (itemtype == 0 &&
+ is_out(map, weight, weight_max, item, x))
+ break;
+
+ /* yay! */
+ out[rep] = item;
+ left--;
+ break;
+ }
+ }
+ }
+ for (rep = outpos; rep < numrep; rep++) {
+ if (out[rep] == CRUSH_ITEM_UNDEF) {
+ out[rep] = CRUSH_ITEM_NONE;
+ }
+ if (out2 && out2[rep] == CRUSH_ITEM_UNDEF) {
+ out2[rep] = CRUSH_ITEM_NONE;
+ }
+ }
+}
+
+/**
* crush_do_rule - calculate a mapping with the given input and rule
* @map: the crush_map
* @ruleno: the rule id
@@ -556,15 +698,27 @@ int crush_do_rule(const struct crush_map *map,
continue;
}
j = 0;
- osize += crush_choose(map,
- map->buckets[-1-w[i]],
- weight, weight_max,
- x, numrep,
- curstep->arg2,
- o+osize, j,
- firstn,
- recurse_to_leaf,
- descend_once, c+osize);
+ if (firstn) {
+ osize += crush_choose(map,
+ map->buckets[-1-w[i]],
+ weight, weight_max,
+ x, numrep,
+ curstep->arg2,
+ o+osize, j,
+ firstn,
+ recurse_to_leaf,
+ descend_once, c+osize);
+ } else {
+ crush_choose_indep(map,
+ map->buckets[-1-w[i]],
+ weight, weight_max,
+ x, numrep,
+ curstep->arg2,
+ o+osize, j,
+ recurse_to_leaf,
+ c+osize);
+ osize += numrep;
+ }
}
if (recurse_to_leaf)
--
1.7.10.4
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