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authorJens Axboe <axboe@kernel.dk>2013-05-15 10:36:25 +0200
committerJens Axboe <axboe@kernel.dk>2013-05-15 10:36:25 +0200
commitc0a363f5cf21f79d72ab630524c3aa06fc6d066c (patch)
tree6127eba7172ab1117dc18fcdc6b08352c736cafd
parent093c959307f2f5af72b24fdc4af7d4d0263f6eea (diff)
parentf59fce847fc8483508b5028c24e2b1e00523dd88 (diff)
downloadlinaro-lsk-c0a363f5cf21f79d72ab630524c3aa06fc6d066c.tar.gz
Merge branch 'bcache-for-upstream' of git://evilpiepirate.org/~kent/linux-bcache into for-linus
Kent writes: Jens - couple more bcache patches. Bug fixes and a doc update.
-rw-r--r--Documentation/bcache.txt12
-rw-r--r--drivers/md/bcache/Kconfig1
-rw-r--r--drivers/md/bcache/bcache.h2
-rw-r--r--drivers/md/bcache/stats.c34
-rw-r--r--drivers/md/bcache/super.c185
-rw-r--r--drivers/md/bcache/writeback.c2
6 files changed, 109 insertions, 127 deletions
diff --git a/Documentation/bcache.txt b/Documentation/bcache.txt
index 77db8809bd9..b3a7e7d384f 100644
--- a/Documentation/bcache.txt
+++ b/Documentation/bcache.txt
@@ -319,7 +319,10 @@ cache<0..n>
Symlink to each of the cache devices comprising this cache set.
cache_available_percent
- Percentage of cache device free.
+ Percentage of cache device which doesn't contain dirty data, and could
+ potentially be used for writeback. This doesn't mean this space isn't used
+ for clean cached data; the unused statistic (in priority_stats) is typically
+ much lower.
clear_stats
Clears the statistics associated with this cache
@@ -423,8 +426,11 @@ nbuckets
Total buckets in this cache
priority_stats
- Statistics about how recently data in the cache has been accessed. This can
- reveal your working set size.
+ Statistics about how recently data in the cache has been accessed.
+ This can reveal your working set size. Unused is the percentage of
+ the cache that doesn't contain any data. Metadata is bcache's
+ metadata overhead. Average is the average priority of cache buckets.
+ Next is a list of quantiles with the priority threshold of each.
written
Sum of all data that has been written to the cache; comparison with
diff --git a/drivers/md/bcache/Kconfig b/drivers/md/bcache/Kconfig
index 05c220d05e2..f950c9d29f3 100644
--- a/drivers/md/bcache/Kconfig
+++ b/drivers/md/bcache/Kconfig
@@ -1,7 +1,6 @@
config BCACHE
tristate "Block device as cache"
- select CLOSURES
---help---
Allows a block device to be used as cache for other devices; uses
a btree for indexing and the layout is optimized for SSDs.
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 340146d7c17..d3e15b42a4a 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -1241,7 +1241,7 @@ void bch_cache_set_stop(struct cache_set *);
struct cache_set *bch_cache_set_alloc(struct cache_sb *);
void bch_btree_cache_free(struct cache_set *);
int bch_btree_cache_alloc(struct cache_set *);
-void bch_writeback_init_cached_dev(struct cached_dev *);
+void bch_cached_dev_writeback_init(struct cached_dev *);
void bch_moving_init_cache_set(struct cache_set *);
void bch_cache_allocator_exit(struct cache *ca);
diff --git a/drivers/md/bcache/stats.c b/drivers/md/bcache/stats.c
index 64e679449c2..b8730e714d6 100644
--- a/drivers/md/bcache/stats.c
+++ b/drivers/md/bcache/stats.c
@@ -93,24 +93,6 @@ static struct attribute *bch_stats_files[] = {
};
static KTYPE(bch_stats);
-static void scale_accounting(unsigned long data);
-
-void bch_cache_accounting_init(struct cache_accounting *acc,
- struct closure *parent)
-{
- kobject_init(&acc->total.kobj, &bch_stats_ktype);
- kobject_init(&acc->five_minute.kobj, &bch_stats_ktype);
- kobject_init(&acc->hour.kobj, &bch_stats_ktype);
- kobject_init(&acc->day.kobj, &bch_stats_ktype);
-
- closure_init(&acc->cl, parent);
- init_timer(&acc->timer);
- acc->timer.expires = jiffies + accounting_delay;
- acc->timer.data = (unsigned long) acc;
- acc->timer.function = scale_accounting;
- add_timer(&acc->timer);
-}
-
int bch_cache_accounting_add_kobjs(struct cache_accounting *acc,
struct kobject *parent)
{
@@ -244,3 +226,19 @@ void bch_mark_sectors_bypassed(struct search *s, int sectors)
atomic_add(sectors, &dc->accounting.collector.sectors_bypassed);
atomic_add(sectors, &s->op.c->accounting.collector.sectors_bypassed);
}
+
+void bch_cache_accounting_init(struct cache_accounting *acc,
+ struct closure *parent)
+{
+ kobject_init(&acc->total.kobj, &bch_stats_ktype);
+ kobject_init(&acc->five_minute.kobj, &bch_stats_ktype);
+ kobject_init(&acc->hour.kobj, &bch_stats_ktype);
+ kobject_init(&acc->day.kobj, &bch_stats_ktype);
+
+ closure_init(&acc->cl, parent);
+ init_timer(&acc->timer);
+ acc->timer.expires = jiffies + accounting_delay;
+ acc->timer.data = (unsigned long) acc;
+ acc->timer.function = scale_accounting;
+ add_timer(&acc->timer);
+}
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index c8046bc4aa5..f88e2b653a3 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -634,11 +634,10 @@ static int open_dev(struct block_device *b, fmode_t mode)
return 0;
}
-static int release_dev(struct gendisk *b, fmode_t mode)
+static void release_dev(struct gendisk *b, fmode_t mode)
{
struct bcache_device *d = b->private_data;
closure_put(&d->cl);
- return 0;
}
static int ioctl_dev(struct block_device *b, fmode_t mode,
@@ -732,8 +731,7 @@ static void bcache_device_free(struct bcache_device *d)
if (d->c)
bcache_device_detach(d);
-
- if (d->disk)
+ if (d->disk && d->disk->flags & GENHD_FL_UP)
del_gendisk(d->disk);
if (d->disk && d->disk->queue)
blk_cleanup_queue(d->disk->queue);
@@ -756,12 +754,9 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size)
if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio))) ||
!(d->unaligned_bvec = mempool_create_kmalloc_pool(1,
sizeof(struct bio_vec) * BIO_MAX_PAGES)) ||
- bio_split_pool_init(&d->bio_split_hook))
-
- return -ENOMEM;
-
- d->disk = alloc_disk(1);
- if (!d->disk)
+ bio_split_pool_init(&d->bio_split_hook) ||
+ !(d->disk = alloc_disk(1)) ||
+ !(q = blk_alloc_queue(GFP_KERNEL)))
return -ENOMEM;
snprintf(d->disk->disk_name, DISK_NAME_LEN, "bcache%i", bcache_minor);
@@ -771,10 +766,6 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size)
d->disk->fops = &bcache_ops;
d->disk->private_data = d;
- q = blk_alloc_queue(GFP_KERNEL);
- if (!q)
- return -ENOMEM;
-
blk_queue_make_request(q, NULL);
d->disk->queue = q;
q->queuedata = d;
@@ -999,14 +990,17 @@ static void cached_dev_free(struct closure *cl)
mutex_lock(&bch_register_lock);
- bd_unlink_disk_holder(dc->bdev, dc->disk.disk);
+ if (atomic_read(&dc->running))
+ bd_unlink_disk_holder(dc->bdev, dc->disk.disk);
bcache_device_free(&dc->disk);
list_del(&dc->list);
mutex_unlock(&bch_register_lock);
if (!IS_ERR_OR_NULL(dc->bdev)) {
- blk_sync_queue(bdev_get_queue(dc->bdev));
+ if (dc->bdev->bd_disk)
+ blk_sync_queue(bdev_get_queue(dc->bdev));
+
blkdev_put(dc->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
}
@@ -1028,73 +1022,67 @@ static void cached_dev_flush(struct closure *cl)
static int cached_dev_init(struct cached_dev *dc, unsigned block_size)
{
- int err;
+ int ret;
struct io *io;
-
- closure_init(&dc->disk.cl, NULL);
- set_closure_fn(&dc->disk.cl, cached_dev_flush, system_wq);
+ struct request_queue *q = bdev_get_queue(dc->bdev);
__module_get(THIS_MODULE);
INIT_LIST_HEAD(&dc->list);
+ closure_init(&dc->disk.cl, NULL);
+ set_closure_fn(&dc->disk.cl, cached_dev_flush, system_wq);
kobject_init(&dc->disk.kobj, &bch_cached_dev_ktype);
-
- bch_cache_accounting_init(&dc->accounting, &dc->disk.cl);
-
- err = bcache_device_init(&dc->disk, block_size);
- if (err)
- goto err;
-
- spin_lock_init(&dc->io_lock);
- closure_init_unlocked(&dc->sb_write);
INIT_WORK(&dc->detach, cached_dev_detach_finish);
+ closure_init_unlocked(&dc->sb_write);
+ INIT_LIST_HEAD(&dc->io_lru);
+ spin_lock_init(&dc->io_lock);
+ bch_cache_accounting_init(&dc->accounting, &dc->disk.cl);
dc->sequential_merge = true;
dc->sequential_cutoff = 4 << 20;
- INIT_LIST_HEAD(&dc->io_lru);
- dc->sb_bio.bi_max_vecs = 1;
- dc->sb_bio.bi_io_vec = dc->sb_bio.bi_inline_vecs;
-
for (io = dc->io; io < dc->io + RECENT_IO; io++) {
list_add(&io->lru, &dc->io_lru);
hlist_add_head(&io->hash, dc->io_hash + RECENT_IO);
}
- bch_writeback_init_cached_dev(dc);
+ ret = bcache_device_init(&dc->disk, block_size);
+ if (ret)
+ return ret;
+
+ set_capacity(dc->disk.disk,
+ dc->bdev->bd_part->nr_sects - dc->sb.data_offset);
+
+ dc->disk.disk->queue->backing_dev_info.ra_pages =
+ max(dc->disk.disk->queue->backing_dev_info.ra_pages,
+ q->backing_dev_info.ra_pages);
+
+ bch_cached_dev_request_init(dc);
+ bch_cached_dev_writeback_init(dc);
return 0;
-err:
- bcache_device_stop(&dc->disk);
- return err;
}
/* Cached device - bcache superblock */
-static const char *register_bdev(struct cache_sb *sb, struct page *sb_page,
+static void register_bdev(struct cache_sb *sb, struct page *sb_page,
struct block_device *bdev,
struct cached_dev *dc)
{
char name[BDEVNAME_SIZE];
const char *err = "cannot allocate memory";
- struct gendisk *g;
struct cache_set *c;
- if (!dc || cached_dev_init(dc, sb->block_size << 9) != 0)
- return err;
-
memcpy(&dc->sb, sb, sizeof(struct cache_sb));
- dc->sb_bio.bi_io_vec[0].bv_page = sb_page;
dc->bdev = bdev;
dc->bdev->bd_holder = dc;
- g = dc->disk.disk;
-
- set_capacity(g, dc->bdev->bd_part->nr_sects - dc->sb.data_offset);
-
- g->queue->backing_dev_info.ra_pages =
- max(g->queue->backing_dev_info.ra_pages,
- bdev->bd_queue->backing_dev_info.ra_pages);
+ bio_init(&dc->sb_bio);
+ dc->sb_bio.bi_max_vecs = 1;
+ dc->sb_bio.bi_io_vec = dc->sb_bio.bi_inline_vecs;
+ dc->sb_bio.bi_io_vec[0].bv_page = sb_page;
+ get_page(sb_page);
- bch_cached_dev_request_init(dc);
+ if (cached_dev_init(dc, sb->block_size << 9))
+ goto err;
err = "error creating kobject";
if (kobject_add(&dc->disk.kobj, &part_to_dev(bdev->bd_part)->kobj,
@@ -1103,6 +1091,8 @@ static const char *register_bdev(struct cache_sb *sb, struct page *sb_page,
if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
goto err;
+ pr_info("registered backing device %s", bdevname(bdev, name));
+
list_add(&dc->list, &uncached_devices);
list_for_each_entry(c, &bch_cache_sets, list)
bch_cached_dev_attach(dc, c);
@@ -1111,15 +1101,10 @@ static const char *register_bdev(struct cache_sb *sb, struct page *sb_page,
BDEV_STATE(&dc->sb) == BDEV_STATE_STALE)
bch_cached_dev_run(dc);
- return NULL;
+ return;
err:
- kobject_put(&dc->disk.kobj);
pr_notice("error opening %s: %s", bdevname(bdev, name), err);
- /*
- * Return NULL instead of an error because kobject_put() cleans
- * everything up
- */
- return NULL;
+ bcache_device_stop(&dc->disk);
}
/* Flash only volumes */
@@ -1717,20 +1702,11 @@ static int cache_alloc(struct cache_sb *sb, struct cache *ca)
size_t free;
struct bucket *b;
- if (!ca)
- return -ENOMEM;
-
__module_get(THIS_MODULE);
kobject_init(&ca->kobj, &bch_cache_ktype);
- memcpy(&ca->sb, sb, sizeof(struct cache_sb));
-
INIT_LIST_HEAD(&ca->discards);
- bio_init(&ca->sb_bio);
- ca->sb_bio.bi_max_vecs = 1;
- ca->sb_bio.bi_io_vec = ca->sb_bio.bi_inline_vecs;
-
bio_init(&ca->journal.bio);
ca->journal.bio.bi_max_vecs = 8;
ca->journal.bio.bi_io_vec = ca->journal.bio.bi_inline_vecs;
@@ -1742,18 +1718,17 @@ static int cache_alloc(struct cache_sb *sb, struct cache *ca)
!init_fifo(&ca->free_inc, free << 2, GFP_KERNEL) ||
!init_fifo(&ca->unused, free << 2, GFP_KERNEL) ||
!init_heap(&ca->heap, free << 3, GFP_KERNEL) ||
- !(ca->buckets = vmalloc(sizeof(struct bucket) *
+ !(ca->buckets = vzalloc(sizeof(struct bucket) *
ca->sb.nbuckets)) ||
!(ca->prio_buckets = kzalloc(sizeof(uint64_t) * prio_buckets(ca) *
2, GFP_KERNEL)) ||
!(ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca)) ||
!(ca->alloc_workqueue = alloc_workqueue("bch_allocator", 0, 1)) ||
bio_split_pool_init(&ca->bio_split_hook))
- goto err;
+ return -ENOMEM;
ca->prio_last_buckets = ca->prio_buckets + prio_buckets(ca);
- memset(ca->buckets, 0, ca->sb.nbuckets * sizeof(struct bucket));
for_each_bucket(b, ca)
atomic_set(&b->pin, 0);
@@ -1766,22 +1741,28 @@ err:
return -ENOMEM;
}
-static const char *register_cache(struct cache_sb *sb, struct page *sb_page,
+static void register_cache(struct cache_sb *sb, struct page *sb_page,
struct block_device *bdev, struct cache *ca)
{
char name[BDEVNAME_SIZE];
const char *err = "cannot allocate memory";
- if (cache_alloc(sb, ca) != 0)
- return err;
-
- ca->sb_bio.bi_io_vec[0].bv_page = sb_page;
+ memcpy(&ca->sb, sb, sizeof(struct cache_sb));
ca->bdev = bdev;
ca->bdev->bd_holder = ca;
+ bio_init(&ca->sb_bio);
+ ca->sb_bio.bi_max_vecs = 1;
+ ca->sb_bio.bi_io_vec = ca->sb_bio.bi_inline_vecs;
+ ca->sb_bio.bi_io_vec[0].bv_page = sb_page;
+ get_page(sb_page);
+
if (blk_queue_discard(bdev_get_queue(ca->bdev)))
ca->discard = CACHE_DISCARD(&ca->sb);
+ if (cache_alloc(sb, ca) != 0)
+ goto err;
+
err = "error creating kobject";
if (kobject_add(&ca->kobj, &part_to_dev(bdev->bd_part)->kobj, "bcache"))
goto err;
@@ -1791,15 +1772,10 @@ static const char *register_cache(struct cache_sb *sb, struct page *sb_page,
goto err;
pr_info("registered cache device %s", bdevname(bdev, name));
-
- return NULL;
+ return;
err:
+ pr_notice("error opening %s: %s", bdevname(bdev, name), err);
kobject_put(&ca->kobj);
- pr_info("error opening %s: %s", bdevname(bdev, name), err);
- /* Return NULL instead of an error because kobject_put() cleans
- * everything up
- */
- return NULL;
}
/* Global interfaces/init */
@@ -1833,12 +1809,15 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
bdev = blkdev_get_by_path(strim(path),
FMODE_READ|FMODE_WRITE|FMODE_EXCL,
sb);
- if (bdev == ERR_PTR(-EBUSY))
- err = "device busy";
-
- if (IS_ERR(bdev) ||
- set_blocksize(bdev, 4096))
+ if (IS_ERR(bdev)) {
+ if (bdev == ERR_PTR(-EBUSY))
+ err = "device busy";
goto err;
+ }
+
+ err = "failed to set blocksize";
+ if (set_blocksize(bdev, 4096))
+ goto err_close;
err = read_super(sb, bdev, &sb_page);
if (err)
@@ -1846,33 +1825,33 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
if (SB_IS_BDEV(sb)) {
struct cached_dev *dc = kzalloc(sizeof(*dc), GFP_KERNEL);
+ if (!dc)
+ goto err_close;
- err = register_bdev(sb, sb_page, bdev, dc);
+ register_bdev(sb, sb_page, bdev, dc);
} else {
struct cache *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
+ if (!ca)
+ goto err_close;
- err = register_cache(sb, sb_page, bdev, ca);
+ register_cache(sb, sb_page, bdev, ca);
}
-
- if (err) {
- /* register_(bdev|cache) will only return an error if they
- * didn't get far enough to create the kobject - if they did,
- * the kobject destructor will do this cleanup.
- */
+out:
+ if (sb_page)
put_page(sb_page);
-err_close:
- blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
-err:
- if (attr != &ksysfs_register_quiet)
- pr_info("error opening %s: %s", path, err);
- ret = -EINVAL;
- }
-
kfree(sb);
kfree(path);
mutex_unlock(&bch_register_lock);
module_put(THIS_MODULE);
return ret;
+
+err_close:
+ blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
+err:
+ if (attr != &ksysfs_register_quiet)
+ pr_info("error opening %s: %s", path, err);
+ ret = -EINVAL;
+ goto out;
}
static int bcache_reboot(struct notifier_block *n, unsigned long code, void *x)
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index 93e7e31a4bd..2714ed3991d 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -375,7 +375,7 @@ err:
refill_dirty(cl);
}
-void bch_writeback_init_cached_dev(struct cached_dev *dc)
+void bch_cached_dev_writeback_init(struct cached_dev *dc)
{
closure_init_unlocked(&dc->writeback);
init_rwsem(&dc->writeback_lock);