Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block

[~andy/linux] / drivers / md / dm-cache-policy-mq.c

diff --git a/drivers/md/dm-cache-policy-mq.c b/drivers/md/dm-cache-policy-mq.c
index d13a16865d03ddc4ec418618d3d8fbdb4909ddc8..1e018e986610a57ef9f82a818aa1f70a8c364e30 100644 (file)
--- a/drivers/md/dm-cache-policy-mq.c
+++ b/drivers/md/dm-cache-policy-mq.c
@@ -287,9 +287,8 @@ static struct entry *alloc_entry(struct entry_pool *ep)
 static struct entry *alloc_particular_entry(struct entry_pool *ep, dm_cblock_t cblock)
 {
        struct entry *e = ep->entries + from_cblock(cblock);
-       list_del(&e->list);
 
-       INIT_LIST_HEAD(&e->list);
+       list_del_init(&e->list);
        INIT_HLIST_NODE(&e->hlist);
        ep->nr_allocated++;
 
@@ -391,6 +390,10 @@ struct mq_policy {
         */
        unsigned promote_threshold;
 
+       unsigned discard_promote_adjustment;
+       unsigned read_promote_adjustment;
+       unsigned write_promote_adjustment;
+
        /*
         * The hash table allows us to quickly find an entry by origin
         * block.  Both pre_cache and cache entries are in here.
@@ -400,6 +403,10 @@ struct mq_policy {
        struct hlist_head *table;
 };
 
+#define DEFAULT_DISCARD_PROMOTE_ADJUSTMENT 1
+#define DEFAULT_READ_PROMOTE_ADJUSTMENT 4
+#define DEFAULT_WRITE_PROMOTE_ADJUSTMENT 8
+
 /*----------------------------------------------------------------*/
 
 /*
@@ -642,25 +649,21 @@ static int demote_cblock(struct mq_policy *mq, dm_oblock_t *oblock)
  * We bias towards reads, since they can be demoted at no cost if they
  * haven't been dirtied.
  */
-#define DISCARDED_PROMOTE_THRESHOLD 1
-#define READ_PROMOTE_THRESHOLD 4
-#define WRITE_PROMOTE_THRESHOLD 8
-
 static unsigned adjusted_promote_threshold(struct mq_policy *mq,
                                           bool discarded_oblock, int data_dir)
 {
        if (data_dir == READ)
-               return mq->promote_threshold + READ_PROMOTE_THRESHOLD;
+               return mq->promote_threshold + mq->read_promote_adjustment;
 
        if (discarded_oblock && (any_free_cblocks(mq) || any_clean_cblocks(mq))) {
                /*
                 * We don't need to do any copying at all, so give this a
                 * very low threshold.
                 */
-               return DISCARDED_PROMOTE_THRESHOLD;
+               return mq->discard_promote_adjustment;
        }
 
-       return mq->promote_threshold + WRITE_PROMOTE_THRESHOLD;
+       return mq->promote_threshold + mq->write_promote_adjustment;
 }
 
 static bool should_promote(struct mq_policy *mq, struct entry *e,
@@ -809,7 +812,7 @@ static int no_entry_found(struct mq_policy *mq, dm_oblock_t oblock,
                          bool can_migrate, bool discarded_oblock,
                          int data_dir, struct policy_result *result)
 {
-       if (adjusted_promote_threshold(mq, discarded_oblock, data_dir) == 1) {
+       if (adjusted_promote_threshold(mq, discarded_oblock, data_dir) <= 1) {
                if (can_migrate)
                        insert_in_cache(mq, oblock, result);
                else
@@ -1135,20 +1138,28 @@ static int mq_set_config_value(struct dm_cache_policy *p,
                               const char *key, const char *value)
 {
        struct mq_policy *mq = to_mq_policy(p);
-       enum io_pattern pattern;
        unsigned long tmp;
 
-       if (!strcasecmp(key, "random_threshold"))
-               pattern = PATTERN_RANDOM;
-       else if (!strcasecmp(key, "sequential_threshold"))
-               pattern = PATTERN_SEQUENTIAL;
-       else
-               return -EINVAL;
-
        if (kstrtoul(value, 10, &tmp))
                return -EINVAL;
 
-       mq->tracker.thresholds[pattern] = tmp;
+       if (!strcasecmp(key, "random_threshold")) {
+               mq->tracker.thresholds[PATTERN_RANDOM] = tmp;
+
+       } else if (!strcasecmp(key, "sequential_threshold")) {
+               mq->tracker.thresholds[PATTERN_SEQUENTIAL] = tmp;
+
+       } else if (!strcasecmp(key, "discard_promote_adjustment"))
+               mq->discard_promote_adjustment = tmp;
+
+       else if (!strcasecmp(key, "read_promote_adjustment"))
+               mq->read_promote_adjustment = tmp;
+
+       else if (!strcasecmp(key, "write_promote_adjustment"))
+               mq->write_promote_adjustment = tmp;
+
+       else
+               return -EINVAL;
 
        return 0;
 }
@@ -1158,9 +1169,16 @@ static int mq_emit_config_values(struct dm_cache_policy *p, char *result, unsign
        ssize_t sz = 0;
        struct mq_policy *mq = to_mq_policy(p);
 
-       DMEMIT("4 random_threshold %u sequential_threshold %u",
+       DMEMIT("10 random_threshold %u "
+              "sequential_threshold %u "
+              "discard_promote_adjustment %u "
+              "read_promote_adjustment %u "
+              "write_promote_adjustment %u",
               mq->tracker.thresholds[PATTERN_RANDOM],
-              mq->tracker.thresholds[PATTERN_SEQUENTIAL]);
+              mq->tracker.thresholds[PATTERN_SEQUENTIAL],
+              mq->discard_promote_adjustment,
+              mq->read_promote_adjustment,
+              mq->write_promote_adjustment);
 
        return 0;
 }
@@ -1213,6 +1231,9 @@ static struct dm_cache_policy *mq_create(dm_cblock_t cache_size,
        mq->hit_count = 0;
        mq->generation = 0;
        mq->promote_threshold = 0;
+       mq->discard_promote_adjustment = DEFAULT_DISCARD_PROMOTE_ADJUSTMENT;
+       mq->read_promote_adjustment = DEFAULT_READ_PROMOTE_ADJUSTMENT;
+       mq->write_promote_adjustment = DEFAULT_WRITE_PROMOTE_ADJUSTMENT;
        mutex_init(&mq->lock);
        spin_lock_init(&mq->tick_lock);
 
@@ -1244,7 +1265,7 @@ bad_pre_cache_init:
 
 static struct dm_cache_policy_type mq_policy_type = {
        .name = "mq",
-       .version = {1, 1, 0},
+       .version = {1, 2, 0},
        .hint_size = 4,
        .owner = THIS_MODULE,
        .create = mq_create
@@ -1252,10 +1273,11 @@ static struct dm_cache_policy_type mq_policy_type = {
 
 static struct dm_cache_policy_type default_policy_type = {
        .name = "default",
-       .version = {1, 1, 0},
+       .version = {1, 2, 0},
        .hint_size = 4,
        .owner = THIS_MODULE,
-       .create = mq_create
+       .create = mq_create,
+       .real = &mq_policy_type
 };
 
 static int __init mq_init(void)