* - set the hit count to a hard coded value other than 1, eg, is it better
* if it goes in at level 2?
*/
-static int demote_cblock(struct mq_policy *mq, dm_oblock_t *oblock)
+static int demote_cblock(struct mq_policy *mq,
+ struct policy_locker *locker, dm_oblock_t *oblock)
{
- struct entry *demoted = pop(mq, &mq->cache_clean);
+ struct entry *demoted = peek(&mq->cache_clean);
if (!demoted)
/*
*/
return -ENOSPC;
+ if (locker->fn(locker, demoted->oblock))
+ /*
+ * We couldn't lock the demoted block.
+ */
+ return -EBUSY;
+
+ del(mq, demoted);
*oblock = demoted->oblock;
free_entry(&mq->cache_pool, demoted);
* finding which cache block to use.
*/
static int pre_cache_to_cache(struct mq_policy *mq, struct entry *e,
+ struct policy_locker *locker,
struct policy_result *result)
{
int r;
/* Ensure there's a free cblock in the cache */
if (epool_empty(&mq->cache_pool)) {
result->op = POLICY_REPLACE;
- r = demote_cblock(mq, &result->old_oblock);
+ r = demote_cblock(mq, locker, &result->old_oblock);
if (r) {
result->op = POLICY_MISS;
return 0;
}
+
} else
result->op = POLICY_NEW;
static int pre_cache_entry_found(struct mq_policy *mq, struct entry *e,
bool can_migrate, bool discarded_oblock,
- int data_dir, struct policy_result *result)
+ int data_dir, struct policy_locker *locker,
+ struct policy_result *result)
{
int r = 0;
else {
requeue(mq, e);
- r = pre_cache_to_cache(mq, e, result);
+ r = pre_cache_to_cache(mq, e, locker, result);
}
return r;
}
static void insert_in_cache(struct mq_policy *mq, dm_oblock_t oblock,
+ struct policy_locker *locker,
struct policy_result *result)
{
int r;
if (epool_empty(&mq->cache_pool)) {
result->op = POLICY_REPLACE;
- r = demote_cblock(mq, &result->old_oblock);
+ r = demote_cblock(mq, locker, &result->old_oblock);
if (unlikely(r)) {
result->op = POLICY_MISS;
insert_in_pre_cache(mq, oblock);
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)
+ int data_dir, struct policy_locker *locker,
+ struct policy_result *result)
{
if (adjusted_promote_threshold(mq, discarded_oblock, data_dir) <= 1) {
if (can_migrate)
- insert_in_cache(mq, oblock, result);
+ insert_in_cache(mq, oblock, locker, result);
else
return -EWOULDBLOCK;
} else {
*/
static int map(struct mq_policy *mq, dm_oblock_t oblock,
bool can_migrate, bool discarded_oblock,
- int data_dir, struct policy_result *result)
+ int data_dir, struct policy_locker *locker,
+ struct policy_result *result)
{
int r = 0;
struct entry *e = hash_lookup(mq, oblock);
else if (e)
r = pre_cache_entry_found(mq, e, can_migrate, discarded_oblock,
- data_dir, result);
+ data_dir, locker, result);
else
r = no_entry_found(mq, oblock, can_migrate, discarded_oblock,
- data_dir, result);
+ data_dir, locker, result);
if (r == -EWOULDBLOCK)
result->op = POLICY_MISS;
static int mq_map(struct dm_cache_policy *p, dm_oblock_t oblock,
bool can_block, bool can_migrate, bool discarded_oblock,
- struct bio *bio, struct policy_result *result)
+ struct bio *bio, struct policy_locker *locker,
+ struct policy_result *result)
{
int r;
struct mq_policy *mq = to_mq_policy(p);
iot_examine_bio(&mq->tracker, bio);
r = map(mq, oblock, can_migrate, discarded_oblock,
- bio_data_dir(bio), result);
+ bio_data_dir(bio), locker, result);
mutex_unlock(&mq->lock);
}
static int mq_writeback_work(struct dm_cache_policy *p, dm_oblock_t *oblock,
- dm_cblock_t *cblock)
+ dm_cblock_t *cblock, bool critical_only)
{
int r;
struct mq_policy *mq = to_mq_policy(p);
return r;
}
-static void mq_tick(struct dm_cache_policy *p)
+static void mq_tick(struct dm_cache_policy *p, bool can_block)
{
struct mq_policy *mq = to_mq_policy(p);
unsigned long flags;
spin_lock_irqsave(&mq->tick_lock, flags);
mq->tick_protected++;
spin_unlock_irqrestore(&mq->tick_lock, flags);
+
+ if (can_block) {
+ mutex_lock(&mq->lock);
+ copy_tick(mq);
+ mutex_unlock(&mq->lock);
+ }
}
static int mq_set_config_value(struct dm_cache_policy *p,
return 0;
}
-static int mq_emit_config_values(struct dm_cache_policy *p, char *result, unsigned maxlen)
+static int mq_emit_config_values(struct dm_cache_policy *p, char *result,
+ unsigned maxlen, ssize_t *sz_ptr)
{
- ssize_t sz = 0;
+ ssize_t sz = *sz_ptr;
struct mq_policy *mq = to_mq_policy(p);
DMEMIT("10 random_threshold %u "
"sequential_threshold %u "
"discard_promote_adjustment %u "
"read_promote_adjustment %u "
- "write_promote_adjustment %u",
+ "write_promote_adjustment %u ",
mq->tracker.thresholds[PATTERN_RANDOM],
mq->tracker.thresholds[PATTERN_SEQUENTIAL],
mq->discard_promote_adjustment,
mq->read_promote_adjustment,
mq->write_promote_adjustment);
+ *sz_ptr = sz;
return 0;
}
static struct dm_cache_policy_type mq_policy_type = {
.name = "mq",
- .version = {1, 3, 0},
+ .version = {1, 4, 0},
.hint_size = 4,
.owner = THIS_MODULE,
.create = mq_create
};
-static struct dm_cache_policy_type default_policy_type = {
- .name = "default",
- .version = {1, 3, 0},
- .hint_size = 4,
- .owner = THIS_MODULE,
- .create = mq_create,
- .real = &mq_policy_type
-};
-
static int __init mq_init(void)
{
int r;
__alignof__(struct entry),
0, NULL);
if (!mq_entry_cache)
- goto bad;
+ return -ENOMEM;
r = dm_cache_policy_register(&mq_policy_type);
if (r) {
DMERR("register failed %d", r);
- goto bad_register_mq;
- }
-
- r = dm_cache_policy_register(&default_policy_type);
- if (!r) {
- DMINFO("version %u.%u.%u loaded",
- mq_policy_type.version[0],
- mq_policy_type.version[1],
- mq_policy_type.version[2]);
- return 0;
+ kmem_cache_destroy(mq_entry_cache);
+ return -ENOMEM;
}
- DMERR("register failed (as default) %d", r);
-
- dm_cache_policy_unregister(&mq_policy_type);
-bad_register_mq:
- kmem_cache_destroy(mq_entry_cache);
-bad:
- return -ENOMEM;
+ return 0;
}
static void __exit mq_exit(void)
{
dm_cache_policy_unregister(&mq_policy_type);
- dm_cache_policy_unregister(&default_policy_type);
kmem_cache_destroy(mq_entry_cache);
}
git.openpandora.org / pandora-kernel.git / blobdiff