crush: merge working data and scratch

Much like Arlo Guthrie, I decided that one big pile is better than two
little piles.

Reflects ceph.git commit 95c2df6c7e0b22d2ea9d91db500cf8b9441c73ba.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/include/linux/ceph/osdmap.h b/include/linux/ceph/osdmap.h
index cef1cab..8cebdc4 100644 (file)
--- a/include/linux/ceph/osdmap.h
+++ b/include/linux/ceph/osdmap.h
@@ -173,8 +173,7 @@ struct ceph_osdmap {
         * the list of osds that store+replicate them. */
        struct crush_map *crush;
 
-       struct mutex crush_scratch_mutex;
-       int crush_scratch_ary[CEPH_PG_MAX_SIZE * 3];
+       struct mutex crush_workspace_mutex;
        void *crush_workspace;
 };
 

diff --git a/include/linux/crush/mapper.h b/include/linux/crush/mapper.h
index 3303c7f..c95e19e 100644 (file)
--- a/include/linux/crush/mapper.h
+++ b/include/linux/crush/mapper.h
@@ -15,7 +15,19 @@ extern int crush_do_rule(const struct crush_map *map,
                         int ruleno,
                         int x, int *result, int result_max,
                         const __u32 *weights, int weight_max,
-                        void *cwin, int *scratch);
+                        void *cwin);
+
+/*
+ * Returns the exact amount of workspace that will need to be used
+ * for a given combination of crush_map and result_max. The caller can
+ * then allocate this much on its own, either on the stack, in a
+ * per-thread long-lived buffer, or however it likes.
+ */
+static inline size_t crush_work_size(const struct crush_map *map,
+                                    int result_max)
+{
+       return map->working_size + result_max * 3 * sizeof(__u32);
+}
 
 void crush_init_workspace(const struct crush_map *map, void *v);
 

diff --git a/net/ceph/crush/mapper.c b/net/ceph/crush/mapper.c
index 9e75be5..2e31217 100644 (file)
--- a/net/ceph/crush/mapper.c
+++ b/net/ceph/crush/mapper.c
@@ -855,23 +855,22 @@ void crush_init_workspace(const struct crush_map *map, void *v)
  * @result_max: maximum result size
  * @weight: weight vector (for map leaves)
  * @weight_max: size of weight vector
- * @cwin: pointer to at least map->working_size bytes of memory
- * @scratch: scratch vector for private use; must be >= 3 * result_max
+ * @cwin: pointer to at least crush_work_size() bytes of memory
  */
 int crush_do_rule(const struct crush_map *map,
                  int ruleno, int x, int *result, int result_max,
                  const __u32 *weight, int weight_max,
-                 void *cwin, int *scratch)
+                 void *cwin)
 {
        int result_len;
        struct crush_work *cw = cwin;
-       int *a = scratch;
-       int *b = scratch + result_max;
-       int *c = scratch + result_max*2;
+       int *a = cwin + map->working_size;
+       int *b = a + result_max;
+       int *c = b + result_max;
+       int *w = a;
+       int *o = b;
        int recurse_to_leaf;
-       int *w;
        int wsize = 0;
-       int *o;
        int osize;
        int *tmp;
        const struct crush_rule *rule;
@@ -902,8 +901,6 @@ int crush_do_rule(const struct crush_map *map,
 
        rule = map->rules[ruleno];
        result_len = 0;
-       w = a;
-       o = b;
 
        for (step = 0; step < rule->len; step++) {
                int firstn = 0;

diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c
index 3892e7f..2374956 100644 (file)
--- a/net/ceph/osdmap.c
+++ b/net/ceph/osdmap.c
@@ -743,7 +743,7 @@ struct ceph_osdmap *ceph_osdmap_alloc(void)
        map->pool_max = -1;
        map->pg_temp = RB_ROOT;
        map->primary_temp = RB_ROOT;
-       mutex_init(&map->crush_scratch_mutex);
+       mutex_init(&map->crush_workspace_mutex);
 
        return map;
 }
@@ -836,11 +836,14 @@ static int osdmap_set_max_osd(struct ceph_osdmap *map, int max)
 static int osdmap_set_crush(struct ceph_osdmap *map, struct crush_map *crush)
 {
        void *workspace;
+       size_t work_size;
 
        if (IS_ERR(crush))
                return PTR_ERR(crush);
 
-       workspace = kmalloc(crush->working_size, GFP_NOIO);
+       work_size = crush_work_size(crush, CEPH_PG_MAX_SIZE);
+       dout("%s work_size %zu bytes\n", __func__, work_size);
+       workspace = kmalloc(work_size, GFP_NOIO);
        if (!workspace) {
                crush_destroy(crush);
                return -ENOMEM;
@@ -1974,11 +1977,10 @@ static int do_crush(struct ceph_osdmap *map, int ruleno, int x,
 
        BUG_ON(result_max > CEPH_PG_MAX_SIZE);
 
-       mutex_lock(&map->crush_scratch_mutex);
+       mutex_lock(&map->crush_workspace_mutex);
        r = crush_do_rule(map->crush, ruleno, x, result, result_max,
-                         weight, weight_max, map->crush_workspace,
-                         map->crush_scratch_ary);
-       mutex_unlock(&map->crush_scratch_mutex);
+                         weight, weight_max, map->crush_workspace);
+       mutex_unlock(&map->crush_workspace_mutex);
 
        return r;
 }